V8 Flapper system - stopped starting!!
Discussion
Hoping to pick the brains of some of the good folk on here!
Have a 3.5 RV8 with flapper type efi fitted in a mk1 Granada by a previous owner. First sign of trouble was a couple of months back when she wouldn't fire up. Couldn't hear the fuel pump priming when turning on the ignition. Had a bit of a poke around with the hidden cut out switch and got her going so put it down to that being a bit iffy.
All was well until yesterday when trying to start her up after two weeks of being parked up in the garage. Again no fuel pump priming so started investigating....hidden cut out switch working ok, main relay coming on with ignition ok, tested fuel pump relay and is functioning, pump operates by bridging white and white/pink high current wires but no current coming in on the white/green.
From what I have now read it seems in this system the fuel pump isn't actually supposed to prime when the ignition is on but only when the engine starts cranking....I was certain it had been priming before but am now beginning to question my sanity!
Anyway, give the flap in the AFM a prod and fuel pump operates. Insert trusty bit of wood to hold it open a little, try the key and she runs for about one second and dies. Try again, same thing. Bridge relay again just for the sake of it, same thing. What has really confused me is that after removing the trusty bit of wood the engine will still fire and run for a second although nothing has actually been altered from the previous state of affairs where there were no signs of life!
Do you think I'm on the right train of thought with the idea that the engine is running briefly from the fuel supplied by the cold start injector but the main injectors aren't operating?
Should I be able to hear the injectors 'clicking' over the sound of the starter motor?
Have done a continuity test on the black/white wire going from the coil negative to pin 1 on the ECU, think this is ok, cheapo budget multimeter gives a reading but decays to zero after a couple of seconds...also does this on a short piece of test wire and when touching the probes together, is this normal?
Connectors in the power resistor multiplug are quite oily, going to clean this up tomorrow when the battery is recharged...coil was new about 150 miles ago, terminals are clean and seem tight.
Apologies for the long post and further grovelling apologies for not owning a TVR (yet) but hopefully someone here will know whats at the bottom of all this....have looked through loads of old threads on here and on the excellent vintage model aeroplane site but couldn't find anything similar.
Cheers!
Have a 3.5 RV8 with flapper type efi fitted in a mk1 Granada by a previous owner. First sign of trouble was a couple of months back when she wouldn't fire up. Couldn't hear the fuel pump priming when turning on the ignition. Had a bit of a poke around with the hidden cut out switch and got her going so put it down to that being a bit iffy.
All was well until yesterday when trying to start her up after two weeks of being parked up in the garage. Again no fuel pump priming so started investigating....hidden cut out switch working ok, main relay coming on with ignition ok, tested fuel pump relay and is functioning, pump operates by bridging white and white/pink high current wires but no current coming in on the white/green.
From what I have now read it seems in this system the fuel pump isn't actually supposed to prime when the ignition is on but only when the engine starts cranking....I was certain it had been priming before but am now beginning to question my sanity!
Anyway, give the flap in the AFM a prod and fuel pump operates. Insert trusty bit of wood to hold it open a little, try the key and she runs for about one second and dies. Try again, same thing. Bridge relay again just for the sake of it, same thing. What has really confused me is that after removing the trusty bit of wood the engine will still fire and run for a second although nothing has actually been altered from the previous state of affairs where there were no signs of life!
Do you think I'm on the right train of thought with the idea that the engine is running briefly from the fuel supplied by the cold start injector but the main injectors aren't operating?
Should I be able to hear the injectors 'clicking' over the sound of the starter motor?
Have done a continuity test on the black/white wire going from the coil negative to pin 1 on the ECU, think this is ok, cheapo budget multimeter gives a reading but decays to zero after a couple of seconds...also does this on a short piece of test wire and when touching the probes together, is this normal?
Connectors in the power resistor multiplug are quite oily, going to clean this up tomorrow when the battery is recharged...coil was new about 150 miles ago, terminals are clean and seem tight.
Apologies for the long post and further grovelling apologies for not owning a TVR (yet) but hopefully someone here will know whats at the bottom of all this....have looked through loads of old threads on here and on the excellent vintage model aeroplane site but couldn't find anything similar.
Cheers!
Here you go V8 Fettler:
Needs the proper mk1 alloys on it really but still gets a lot of admiration...will be going up for sale as soon as she's running again due to me being laid off recently and having to sell off some toys just to pay the bills. Gutted!!
Didn't get the early start I hoped for today due to getting a puncture on the way home from the workshop last night...and finding the spare flat as well! Then having to find a tyre place open on a Sunday with the right size in stock and having to lug the wheel across town on the bus....what with that and the Granada not starting and the botched haircut I got yesterday things aren't going too well at all! Must be due some good luck soon?
Pretty sure the pump kept running yesterday when it was firing briefly but will try the direct feed in a bit when I've cleaned up the power resistor multiplug - nothing to lose!
Wild Rover - whereabouts in the system is the rectifier you mentioned? Don't think I've seen that on any circuit diagrams?
Many thanks for the replies - much appreciated!
Needs the proper mk1 alloys on it really but still gets a lot of admiration...will be going up for sale as soon as she's running again due to me being laid off recently and having to sell off some toys just to pay the bills. Gutted!!
Didn't get the early start I hoped for today due to getting a puncture on the way home from the workshop last night...and finding the spare flat as well! Then having to find a tyre place open on a Sunday with the right size in stock and having to lug the wheel across town on the bus....what with that and the Granada not starting and the botched haircut I got yesterday things aren't going too well at all! Must be due some good luck soon?
Pretty sure the pump kept running yesterday when it was firing briefly but will try the direct feed in a bit when I've cleaned up the power resistor multiplug - nothing to lose!
Wild Rover - whereabouts in the system is the rectifier you mentioned? Don't think I've seen that on any circuit diagrams?
Many thanks for the replies - much appreciated!
Cheers Wedg1e, very much appreciated mate.
Got the ECU connected back up, cleaned up power resistor and AFM multiplugs but now it seems we're back to square one where it's not even firing up for a second as it was yesterday.
Can't hear the injectors clicking when snapping the throttle open...there is some kind of sound coming from under the bonnet but I think it's coming from the throttle linkage.
Have 12v on the two brown/orange wires at the power resistor multiplug but virtually nothing on the others - around 0.05-0.1v (doesn't help that my cheapo multimeter has now decided to sit at 0.13v when not connected to anything).
Thinking then this may point to a break between the ECU and the injectors...or an ECU fault?
Got the ECU connected back up, cleaned up power resistor and AFM multiplugs but now it seems we're back to square one where it's not even firing up for a second as it was yesterday.
Can't hear the injectors clicking when snapping the throttle open...there is some kind of sound coming from under the bonnet but I think it's coming from the throttle linkage.
Have 12v on the two brown/orange wires at the power resistor multiplug but virtually nothing on the others - around 0.05-0.1v (doesn't help that my cheapo multimeter has now decided to sit at 0.13v when not connected to anything).
Thinking then this may point to a break between the ECU and the injectors...or an ECU fault?
Yes have bridged the high current terminals on the fuel pump relay as this was easier than taking the battery off my daily driver and rigging it up that way.
Love the mk2's as well, tough call on which is better looking I think. Not a manual sadly, has a ZF 4 speed auto out of a BMW on a Sherpa (I think) bellhousing...was planning to do the manual conversion but now need to sell her on...would make quite a weapon with a proper cog swapper!
Have been through the test procedure on the vintage model aeroplane site for checking the injection circuitry - Voltage between injector ECU connector pins and ground with ignition on is 12.15v...resistance between pins and terminal 87 on main relay is 8.6ohms...resistance of power resistor is 5.6ohms...all uniform and bang on where they should be it seems? Not tested the injectors themselves but think the above would show up any problem with them or with a bad connection somewhere?
Have even just put another gallon of fuel in just in case I was being really stupid but still not going.
Was just about to check for the spark, although it was obviously working for a bit yesterday.
Also wondering about a possible fuel pressure regulator problem or maybe a collapsed fuel hose? Shame I don't have a pressure gauge....
Or still maybe duff ECU?
Love the mk2's as well, tough call on which is better looking I think. Not a manual sadly, has a ZF 4 speed auto out of a BMW on a Sherpa (I think) bellhousing...was planning to do the manual conversion but now need to sell her on...would make quite a weapon with a proper cog swapper!
Have been through the test procedure on the vintage model aeroplane site for checking the injection circuitry - Voltage between injector ECU connector pins and ground with ignition on is 12.15v...resistance between pins and terminal 87 on main relay is 8.6ohms...resistance of power resistor is 5.6ohms...all uniform and bang on where they should be it seems? Not tested the injectors themselves but think the above would show up any problem with them or with a bad connection somewhere?
Have even just put another gallon of fuel in just in case I was being really stupid but still not going.
Was just about to check for the spark, although it was obviously working for a bit yesterday.
Also wondering about a possible fuel pressure regulator problem or maybe a collapsed fuel hose? Shame I don't have a pressure gauge....
Or still maybe duff ECU?
Yes pump running constantly with ignition on, put another gallon of fuel in today, is still in the red though to be fair although it did drive into the garage under it's own steam two weeks ago.
Tried working the throttle linkage by hand with my head under the bonnet but can't hear any click, will try to find out which wires to bridge on the TPS.
Struggled for about 15 minutes trying to check the spark but no joy with only one pair of hands, just reading up on how to check out the components with a meter until I can get someone to give me a hand with this.
Breaking into the fuel line could be next on the cards, think I read something about depressurising it beforehand?
One other thing is that I can't seem to see the inline resistor that should be in the wire between the coil -ve and ECU pin 1?
Tried working the throttle linkage by hand with my head under the bonnet but can't hear any click, will try to find out which wires to bridge on the TPS.
Struggled for about 15 minutes trying to check the spark but no joy with only one pair of hands, just reading up on how to check out the components with a meter until I can get someone to give me a hand with this.
Breaking into the fuel line could be next on the cards, think I read something about depressurising it beforehand?
One other thing is that I can't seem to see the inline resistor that should be in the wire between the coil -ve and ECU pin 1?
^^^^If only it was always that quick a fix!
Slight faux pas on my part seems I left the coil +ve connection to the ignition amplifier disconnected last night and failed to spot it due to the coil being hidden under the AFM. Whoops!!
Nice bright blue spark at the plug and we're back to the engine running for a second then dying. Still can't hear injectors clicking with ignition on so thinking test the TPS next? Engine will rev up before dying if you start it with the accelerator pedal down but I suppose this could be down to the throttle butterfly being open even if the TPS is faulty? Engine does hunt/surge a little sometimes if that's an indicator? Had initially suspected an air leak somewhere in the inlet.
Out of time now for today but thanks again to everyone for the input!
Slight faux pas on my part seems I left the coil +ve connection to the ignition amplifier disconnected last night and failed to spot it due to the coil being hidden under the AFM. Whoops!!
Nice bright blue spark at the plug and we're back to the engine running for a second then dying. Still can't hear injectors clicking with ignition on so thinking test the TPS next? Engine will rev up before dying if you start it with the accelerator pedal down but I suppose this could be down to the throttle butterfly being open even if the TPS is faulty? Engine does hunt/surge a little sometimes if that's an indicator? Had initially suspected an air leak somewhere in the inlet.
Out of time now for today but thanks again to everyone for the input!
RCK - Think the original rover setup had a resistor inline from the coil negative to the ECU but can't see it on mine (unless it's taped up inside the loom), general consensus seems to be that it's not required. Engine won't fire at all with this wire disconnected and continuity test seems ok so it must be doing something....had wondered about running another wire in parallel just in case though?
Wild Rover - Have tested the power resistor and seems within spec, has power to it but have a conspicuous lack of volts coming from the injectors. Relays are powered up so at least that's something!
Definitely no injector clicks either from unplugging and reconnecting TPS or even from bridging the red and yellow wires so I guess this ties in with the lack of volts at the power resistor? I assume there's no way of testing voltage at the injector without the engine running? Thinking there must be a break between injectors and ECU or between injectors and power resistor as per V8 Fettler's experience?
Does anyone know if there's normally a multiplug between ECU/injectors and injectors/power resistor that might be taped up inside the loom or are they all run directly?
Slightly confusing though as the tests carried out on the injector circuitry as per the vintage model aeroplane site all checked out ok?
Also, the engine will still fire briefly with the CSI disconnected whereas it won't with the power resistor unplugged so the injectors must be doing something?
Cobbled the pressure gauge from my compressor into the CSI fuel feed....registers 30 psi (a bit low but could be cheap and inaccurate) and holds it. After the engine dies and with the pump still running there is a sloshing/liquid flowing sort of noise which my handy length of hosepipe tells me is coming from the FPR so I think that means it works? Or is it that the spring is weak and it's not working?
Thought I had it sussed earlier when I noticed a split in the vacuum hose from the plenum to the FPR - but no!
Really overwhelmed by all the help received on here - thanks!!
Wild Rover - Have tested the power resistor and seems within spec, has power to it but have a conspicuous lack of volts coming from the injectors. Relays are powered up so at least that's something!
Definitely no injector clicks either from unplugging and reconnecting TPS or even from bridging the red and yellow wires so I guess this ties in with the lack of volts at the power resistor? I assume there's no way of testing voltage at the injector without the engine running? Thinking there must be a break between injectors and ECU or between injectors and power resistor as per V8 Fettler's experience?
Does anyone know if there's normally a multiplug between ECU/injectors and injectors/power resistor that might be taped up inside the loom or are they all run directly?
Slightly confusing though as the tests carried out on the injector circuitry as per the vintage model aeroplane site all checked out ok?
Also, the engine will still fire briefly with the CSI disconnected whereas it won't with the power resistor unplugged so the injectors must be doing something?
Cobbled the pressure gauge from my compressor into the CSI fuel feed....registers 30 psi (a bit low but could be cheap and inaccurate) and holds it. After the engine dies and with the pump still running there is a sloshing/liquid flowing sort of noise which my handy length of hosepipe tells me is coming from the FPR so I think that means it works? Or is it that the spring is weak and it's not working?
Thought I had it sussed earlier when I noticed a split in the vacuum hose from the plenum to the FPR - but no!
Really overwhelmed by all the help received on here - thanks!!
It...ahem...seems it isn't! Just tried and it will try to start in all gears!
Had a look underneath and can't see a switch or any wires in the area...wonder if the more modern BMW that the box is from had a sensor in the lever assembly or some other high tech way of inhibiting the starter?
Had a look underneath and can't see a switch or any wires in the area...wonder if the more modern BMW that the box is from had a sensor in the lever assembly or some other high tech way of inhibiting the starter?
Adam - It will run for about one second before dying...if you plant the throttle it will rev up quickly but still die after a second.
Don't think it's sooty although it does smell of fuel, but it did a bit anyway before this problem reared it's head. Drove ok 2 weeks ago but is now playing up the first time I tried to start it again.
Won't fire at all with trigger wire disconnected and continuity test seems ok, injectors aren't clicking when snapping the throttle on and voltage is more or less absent at the power resistor on the 8 wires coming from the injectors. No oscilloscope I'm afraid, have started unwrapping the loom looking for breaks in the wiring but can't see any connectors in the circuit, would be odd for all 8 to give up at once? Worried it may be an ECU fault although checking voltage from ECU pins was ok, as was circuit continuity test and power resistor test.
Yes is an auto, starter works fine, box is from 90's (I think) BMW, can't see an inhibitor switch on gearbox, wonder if it may be in lever mechanism or operates some other way in the original car, will start and try to run in any gear!
Don't think it's sooty although it does smell of fuel, but it did a bit anyway before this problem reared it's head. Drove ok 2 weeks ago but is now playing up the first time I tried to start it again.
Won't fire at all with trigger wire disconnected and continuity test seems ok, injectors aren't clicking when snapping the throttle on and voltage is more or less absent at the power resistor on the 8 wires coming from the injectors. No oscilloscope I'm afraid, have started unwrapping the loom looking for breaks in the wiring but can't see any connectors in the circuit, would be odd for all 8 to give up at once? Worried it may be an ECU fault although checking voltage from ECU pins was ok, as was circuit continuity test and power resistor test.
Yes is an auto, starter works fine, box is from 90's (I think) BMW, can't see an inhibitor switch on gearbox, wonder if it may be in lever mechanism or operates some other way in the original car, will start and try to run in any gear!
Engine code is 25d*****c which I believe makes it a Range Rover lump.
Can't see an inertia switch, am I right in thinking this is normally in the AFM area of the loom?
Think this swerving, curving ball may turn out to be something out of the ordinary or down to extreme stupidity on my part! Have at least checked the earths and they are tight, will do continuity test when I've got the loom unwrapped.
Cheers!
Can't see an inertia switch, am I right in thinking this is normally in the AFM area of the loom?
Think this swerving, curving ball may turn out to be something out of the ordinary or down to extreme stupidity on my part! Have at least checked the earths and they are tight, will do continuity test when I've got the loom unwrapped.
Cheers!
Checking TPS voltage between centre (red) pin and ground gives a maximum of 3.77v and seems to increase smoothly when turned slowly as far as I can tell with a digital multimeter. Does the same when connected between red and green.
From what I've read the voltage between red and green should be around 0.325v with the throttle closed but am only reading 0.02v but then again my low quality meter seems to sit at 0.13v when not connected to anything so that's not really helping matters.
If I wasn't completely potless at the moment (pun intended) I'd try to get a replacement TPS on there to confirm or rule it out but not at all possible I'm afraid!
From what I've read the voltage between red and green should be around 0.325v with the throttle closed but am only reading 0.02v but then again my low quality meter seems to sit at 0.13v when not connected to anything so that's not really helping matters.
If I wasn't completely potless at the moment (pun intended) I'd try to get a replacement TPS on there to confirm or rule it out but not at all possible I'm afraid!
Yep, they're up under the dash near the ECU.
Tried moving the TPS round both ways to see if that made a difference, but no. Very carefully took the lid off the ECU to check for any burnt component smell, but no. Solder on the outsides of the 2 boards looks nice and shiny.
Jobs for tomorrow night are to get the rest of the loom unwrapped and look for breaks, check voltage at injectors, check continuity between ECU and injectors, between injectors and power resistor, between TPS and ECU, check earths, check anything else I can find that is taped up in the loom, test injectors, test temperature sender.
The lack of voltage at the power resistor and lack of injector click must be a clue although the fact that it doesn't fire at all with the power resistor unplugged means the injectors must be doing something though?
At least there will be the reward of the V8 growl at the end of all this!
Quote: "The Diagnostic Challenge Continues"!!!!
Tried moving the TPS round both ways to see if that made a difference, but no. Very carefully took the lid off the ECU to check for any burnt component smell, but no. Solder on the outsides of the 2 boards looks nice and shiny.
Jobs for tomorrow night are to get the rest of the loom unwrapped and look for breaks, check voltage at injectors, check continuity between ECU and injectors, between injectors and power resistor, between TPS and ECU, check earths, check anything else I can find that is taped up in the loom, test injectors, test temperature sender.
The lack of voltage at the power resistor and lack of injector click must be a clue although the fact that it doesn't fire at all with the power resistor unplugged means the injectors must be doing something though?
At least there will be the reward of the V8 growl at the end of all this!
Quote: "The Diagnostic Challenge Continues"!!!!
I checked voltages at all the pins with the ignition on when the problem first started but that was before I found out that the pump isn't energised until the engine is cranked. Don't have a second pair of hands to help out probably until the weekend. Pump runs ok when AFM flap is opened so I think this means the steering module is ok?
Have the fuel pump relay high current terminals bridged so the pump comes on with the ignition so in theory it should run ok given no other faults?
Have the fuel pump relay high current terminals bridged so the pump comes on with the ignition so in theory it should run ok given no other faults?
Scatter Gun haha!!
Yes terminals 30/51 & 87 are bridged. Tomorrow will try removing the bridge wire but I think it still does the cutting out after one second thing from when I tried it on saturday. Had just left it bridged as a belt and braces measure.
Seems to makes sense that with it bridged the engine should run given no other faults, unless power is being cut to terminal 30/51 once the engine fires/starter is disengaged? Which would maybe explain the symptoms and point to... dodgy ignition feed or steering module? Should be able to rig the multimeter up in the passenger footwell tomorrow and watch it when trying to start the engine without needing a second pair of hands.
Think that makes sense but then it has been quite a challenging few days so maybe not?
Nice one anyway V8 Fettler!
Yes terminals 30/51 & 87 are bridged. Tomorrow will try removing the bridge wire but I think it still does the cutting out after one second thing from when I tried it on saturday. Had just left it bridged as a belt and braces measure.
Seems to makes sense that with it bridged the engine should run given no other faults, unless power is being cut to terminal 30/51 once the engine fires/starter is disengaged? Which would maybe explain the symptoms and point to... dodgy ignition feed or steering module? Should be able to rig the multimeter up in the passenger footwell tomorrow and watch it when trying to start the engine without needing a second pair of hands.
Think that makes sense but then it has been quite a challenging few days so maybe not?
Nice one anyway V8 Fettler!
See what you mean V8 Fettler about the main relay being involved in the injector firing by joining into the power resistor wiring...main relay definitely coming on with the ignition but what I don't know is if it's going off again once the engine fires...which again would explain the symptoms. I see this wire goes back to the switch in the AFM that operates the fuel pump maybe there is a fault there that allows it to run just on ignition but breaks down once it's firing?
Or maybe as Adam says the ECU is just knackered!! Glad you think the TPS sounds non-fatal...will test injector system wires individually tomorrow.
Been racking my brains but can't think of anyone I know who'd have an ECU...bit ashamed of myself for not knowing enough people with V8's!
Or maybe as Adam says the ECU is just knackered!! Glad you think the TPS sounds non-fatal...will test injector system wires individually tomorrow.
Been racking my brains but can't think of anyone I know who'd have an ECU...bit ashamed of myself for not knowing enough people with V8's!
Cheers for all the info everyone and good to know there's a fellow rum drinker on board Wedg1e!
Am down south in the Bournemouth/Ringwood area.
Yep, still have 12v on the 2 orange/brown wires at the power resistor but next to nothing on the other 8 although when unplugged the engine won't even fire briefly.
Haven't accidentally swapped the relays, problem started after being parked for 2 weeks and didn't touch anything in the meantime.
Will check voltage at the injectors when I can get over to the workshop this evening. Will also remove the bridging wire on the fuel pump relay and check voltages at both relays and steering module when cranking to see if the pump is shutting down when the engine fires and coming back on as soon as it dies.
With regards to Wedg1e's pre-rum post, I do have 12v at the ECU multiplug yet at the same time nothing at the power resistor which seems impossible if I'm understanding it right? And am getting a reading of 5.6ohms through all 8 pins of the power resistor which implies the 'resistors' haven't broken down?
Am going to try running another wire from the coil -ve to ECU pin 1 just to see as although the continuity test seems ok a fault here would explain the symptoms...but not the lack of voltage at the power resistor.
Haven't seen a ballast resistor yet but will carry on looking, think the original Essex V6 did use one but in the guise of a high resistance wire...but the wiring to the coil is now all part of the Rover loom....I think!
V8 Fettler - What do you mean by 'flicking' the coil -ve wire exactly? Putting 12v to it?
Just had a thought...should I be looking for voltage at the power resistor with the plug connected? I've been measuring with it disconnected? Am I being stupid?
Cheers!
Am down south in the Bournemouth/Ringwood area.
Yep, still have 12v on the 2 orange/brown wires at the power resistor but next to nothing on the other 8 although when unplugged the engine won't even fire briefly.
Haven't accidentally swapped the relays, problem started after being parked for 2 weeks and didn't touch anything in the meantime.
Will check voltage at the injectors when I can get over to the workshop this evening. Will also remove the bridging wire on the fuel pump relay and check voltages at both relays and steering module when cranking to see if the pump is shutting down when the engine fires and coming back on as soon as it dies.
With regards to Wedg1e's pre-rum post, I do have 12v at the ECU multiplug yet at the same time nothing at the power resistor which seems impossible if I'm understanding it right? And am getting a reading of 5.6ohms through all 8 pins of the power resistor which implies the 'resistors' haven't broken down?
Am going to try running another wire from the coil -ve to ECU pin 1 just to see as although the continuity test seems ok a fault here would explain the symptoms...but not the lack of voltage at the power resistor.
Haven't seen a ballast resistor yet but will carry on looking, think the original Essex V6 did use one but in the guise of a high resistance wire...but the wiring to the coil is now all part of the Rover loom....I think!
V8 Fettler - What do you mean by 'flicking' the coil -ve wire exactly? Putting 12v to it?
Just had a thought...should I be looking for voltage at the power resistor with the plug connected? I've been measuring with it disconnected? Am I being stupid?
Cheers!
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