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Leaky Injectors Test
1. Wedged the AFM open turned ignition on to prime fuel pump and pressurise system.
2. I disconnected the resistor pack
3. I left it about 5 minutes and then tried to start
4. It started and ran for a second then cut out.
I then repeated test and it DID NOT fire at all
I'm guessing the reason it started first time is due to leak down test in previous post possibly leaving fuel in system.
Header Temperatures
1. Reconnected resistor pack and the car started frst time and settled into a high idle around 1800rpm
2. After a few minutes the header temps were all consistently 390/400 c
3. As the car got to temperature and came down to 1200 rpm it suddenly got into difficulty.
4. The idle dropped to below 900 rpm and needed regular throttle tweakingto keep running.
5. At this point all headers were 400 odd degrees APART FROM NUMBER 5 which showed 182c.
6. Removing plug lead on number 5 did not affect idle.
Why did number 5 just cut out?
The engine then cut out and I went to restart but relay click only in start position and voltmeter reading low.
Volts/ignition switch
Following on from above
This video shows pretty well the strange behaviour - all I was doing was turning the ignition key.
Watch Battery light whose brightness mirrors the voltmeter readings. Starter motor only attempts to kick in at end.
https://www.youtube.com/watch?v=EMxyi_hFlRA&li...
Could this be 'key' (see what I did there) to strange running?
I'm carrying on with fault finding but gonna list the car on ebay tonight for offers to see if there's any interest as I don't want it to sit through another winter seeing as how that seemed to cause loads of issues first time round and I'm ready to take the inevitable hit now.
1. Wedged the AFM open turned ignition on to prime fuel pump and pressurise system.
2. I disconnected the resistor pack
3. I left it about 5 minutes and then tried to start
4. It started and ran for a second then cut out.
I then repeated test and it DID NOT fire at all
I'm guessing the reason it started first time is due to leak down test in previous post possibly leaving fuel in system.
Header Temperatures
1. Reconnected resistor pack and the car started frst time and settled into a high idle around 1800rpm
2. After a few minutes the header temps were all consistently 390/400 c
3. As the car got to temperature and came down to 1200 rpm it suddenly got into difficulty.
4. The idle dropped to below 900 rpm and needed regular throttle tweakingto keep running.
5. At this point all headers were 400 odd degrees APART FROM NUMBER 5 which showed 182c.
6. Removing plug lead on number 5 did not affect idle.
Why did number 5 just cut out?
The engine then cut out and I went to restart but relay click only in start position and voltmeter reading low.
Volts/ignition switch
Following on from above
This video shows pretty well the strange behaviour - all I was doing was turning the ignition key.
Watch Battery light whose brightness mirrors the voltmeter readings. Starter motor only attempts to kick in at end.
https://www.youtube.com/watch?v=EMxyi_hFlRA&li...
Could this be 'key' (see what I did there) to strange running?
I'm carrying on with fault finding but gonna list the car on ebay tonight for offers to see if there's any interest as I don't want it to sit through another winter seeing as how that seemed to cause loads of issues first time round and I'm ready to take the inevitable hit now.
Edited by smash on Sunday 17th August 13:02
On a v8 on cylinder cutting out is not the end of the world, you may have a sticky injector on that cyl, Reading back through your tales of woe and looking at the video are you sure about all the earth's as both the starter and injection connect back to the engine block loosing connection between the battery and block would explain the odd voltmeter behaviour, the fact that the it stops and the failing to crank ? One of the local TVRCC members had a similar issue with a V8s, it would run for a bit then not even turn over.
Easy test would be to stick a jump lead from the engine block to the battery -ve.
Easy test would be to stick a jump lead from the engine block to the battery -ve.
The voltmeter problem is probably a poor electrical connection somewhere - not necessarily an earth but maybe +ve supply. Check battery terminals and feeds to starter motor and fuse box and relays
Lost my way on where you are on diagnosing your poor (or lack of)running - should have done a flow chart
!
Just go back over the basics and see where you are
Set timing to tdc - ignore timing marks as they're wrong - once running can be fine tuned
Check and set all Efi equipment as per honest johns info
Check nice fat spark at each plug
Check for any air leaks in intake system
You know you've got compression and fuel pressure, so that with correct timing a good spark and the efi set properly should get you going?
Failing that I'll keep an eye on the bay and put in a cheeky bid Lol
Good luck
Lost my way on where you are on diagnosing your poor (or lack of)running - should have done a flow chart
! Just go back over the basics and see where you are
Set timing to tdc - ignore timing marks as they're wrong - once running can be fine tuned
Check and set all Efi equipment as per honest johns info
Check nice fat spark at each plug
Check for any air leaks in intake system
You know you've got compression and fuel pressure, so that with correct timing a good spark and the efi set properly should get you going?
Failing that I'll keep an eye on the bay and put in a cheeky bid Lol
Good luck
Looks like you have two/three problems:
1. The battery is losing charge (following your threads you keep having to charge the battery). Given that you can start the car when the battery is charged I don't think it's the problem, more likely the alternator. You can get a new one for about £50 off the flea - I fitted one of these:
http://www.ebay.co.uk/itm/NEW-ALTERNATOR-12V-VOLT-...
When the engine voltage droops you get all sorts of weird running effects. Of course it might be the wiring to the alternator, especially the field supply, so check that first.
2. Dodgy ignition switch (or wiring).
3. No 5 cylinder - some sort of injector problem? If it's the leaky one then it might be flooding that cylinder and it won't fire there, plus might make all the others run rich too. YOU CAN RUN THE ENGINE ON 7 CYLINDERS. So a quick fix for now it to disconnect No 5 injector plug. It should then run without the temperature effect. When you've confirmed this, order a new one.
1. The battery is losing charge (following your threads you keep having to charge the battery). Given that you can start the car when the battery is charged I don't think it's the problem, more likely the alternator. You can get a new one for about £50 off the flea - I fitted one of these:
http://www.ebay.co.uk/itm/NEW-ALTERNATOR-12V-VOLT-...
When the engine voltage droops you get all sorts of weird running effects. Of course it might be the wiring to the alternator, especially the field supply, so check that first.
2. Dodgy ignition switch (or wiring).
3. No 5 cylinder - some sort of injector problem? If it's the leaky one then it might be flooding that cylinder and it won't fire there, plus might make all the others run rich too. YOU CAN RUN THE ENGINE ON 7 CYLINDERS. So a quick fix for now it to disconnect No 5 injector plug. It should then run without the temperature effect. When you've confirmed this, order a new one.
The loss of one cylinder on a well-fettled RV8 should make very little difference to the reliability of the idle, but if something else is marginal then the engine could cut out. Can't see vid on this handheld, but swop plug from #5 to another, see if fault transfers. Can't recall if dizzy cap is new, but check for green crap to terminal for #5. Have you marked HT leads both ends and HT cap with cylinder numbers? Seems reasonably certain that firing order is correct, need to freeze that position. Prepare to swop ht lead for #5 with another ht lead (both ends to maintain correct firing order;). Don't forget: One step at a time and then test. The aim being to get a reliable idle then go from there.
If this doesn't move things forward then prepare to increase fuel pressure to - say - 45 psi, but don't confuse the issue at the moment.
Not certain if a wobbly trumpet can interfere with the running of one cylinder, have you had a look in the plenum?
Edit to add: Deal with the battery issue with an Oximiser or similar
If this doesn't move things forward then prepare to increase fuel pressure to - say - 45 psi, but don't confuse the issue at the moment.
Not certain if a wobbly trumpet can interfere with the running of one cylinder, have you had a look in the plenum?
Edit to add: Deal with the battery issue with an Oximiser or similar
Edited by V8 Fettler on Sunday 17th August 17:11
Smash has a fuel pressure gauge so he can check fuel pressure when its running and add that to his flowchart (perhaps this has already occurred). I think this has gone behind the scenes now judging by mention of PMs.
Overall, the current symptoms replicate faulty coolant temp sensor data: Good cold start, developing into a blubbery warm idle that fails + sooty plugs. As I recall, Smash has already looked at this. Needs to sort out what is happening with #5 first though.
Overall, the current symptoms replicate faulty coolant temp sensor data: Good cold start, developing into a blubbery warm idle that fails + sooty plugs. As I recall, Smash has already looked at this. Needs to sort out what is happening with #5 first though.
f
k me! Why is everything on these cars so fking difficult - argh!
New ignition switch arrived - Rover SD1 s2 - clearly the same switch, same number of wires just connected differently and with different plug. I foolishly assumed that TVR wouldn't have messed with the loom on a stock part like that but apparently they must have.
I did check images of TR7 switch before and wasn't that - too few wires, which left SD1 S1 or S2 - S1 too few wires, S2 looked right but just needs 'tweeking' apparently...do I not like this fking car!!!
"And relax...."
k me! Why is everything on these cars so fking difficult - argh!New ignition switch arrived - Rover SD1 s2 - clearly the same switch, same number of wires just connected differently and with different plug. I foolishly assumed that TVR wouldn't have messed with the loom on a stock part like that but apparently they must have.
I did check images of TR7 switch before and wasn't that - too few wires, which left SD1 S1 or S2 - S1 too few wires, S2 looked right but just needs 'tweeking' apparently...do I not like this f
king car!!!"And relax...."
Inspired by Mr Maston I have set about removing the old ignition switch and swapping the loom onto the new one then refitting.
All relatively painless and I now have an ignition switch with a very positive click and feel.
So reconnect battery and several turns to position one reveal no strange Volt gauge behaviour. So far so good.
Crank the engine and it started immediately.
After 30 seconds it died however and required a helluva lot of cranking to restart. this proved that the ignition switch appears to have cured the starter motor cutting out problem. This is also good.
My little fettling spark indicators were flashing away merrily so as previously thought this is down to fueling.
After a fair bit of cranking started it with throttle cracked partially open and seemed happy enough settling into fast idle but then rain stopped play for today.
Next stop run up and monitor header temps again and check where the CO is at with a borrowed Gunsons analyser.
All relatively painless and I now have an ignition switch with a very positive click and feel.
So reconnect battery and several turns to position one reveal no strange Volt gauge behaviour. So far so good.
Crank the engine and it started immediately.
After 30 seconds it died however and required a helluva lot of cranking to restart. this proved that the ignition switch appears to have cured the starter motor cutting out problem. This is also good.
My little fettling spark indicators were flashing away merrily so as previously thought this is down to fueling.
After a fair bit of cranking started it with throttle cracked partially open and seemed happy enough settling into fast idle but then rain stopped play for today.
Next stop run up and monitor header temps again and check where the CO is at with a borrowed Gunsons analyser.
Hi Mate...Get it to run and idle first...My betting is still on the fuel pump or failing FPR..If you had a fuel pressure gauge can you not put it between the FPR and fuel rail?....Then crank it to see what fuel pressure is coming from the FPR...If it fluctuates then it could either be the FPR diaphragm failing or the pump could be starting to fail...I have a spare FPR that is set to 2.5 bar if you want to borrow it to test, Hopefully be at the Diner Saturday....Ziga
Hi mate - sorry should've been clearer when I said rain stopped play what I meant was I turned the engine off - it was idling quite happily in fast idle mode as it was warming up. Restarting is the problem very likely due to running very rich (as evidenced last time I checked with wideband lambda)
There is a gauge permanently plumbed in on the cold start feed line (used it for the leak test previously and to set up max pressure when it all kicked off a bit about 38psi, 44psi or 48psi or whatever it was, lol!) and no fluctuations noticed apart from usual vaccuum induced on the FPR.
There is a gauge permanently plumbed in on the cold start feed line (used it for the leak test previously and to set up max pressure when it all kicked off a bit about 38psi, 44psi or 48psi or whatever it was, lol!) and no fluctuations noticed apart from usual vaccuum induced on the FPR.
Mmmm...It should still run even if you are spitting fuel out the exhaust..Ive seen a couple do that and looks cool when it ignites now and then...36-38psi should be sufficient for a 390SE..Max 40-42psi..If its running at 48psi then you have a failing FPR...Thats why i say put the gauge in between the fuel rail and FPR...If you are taking a reading from the cold start then the rail is already pressurised and i would imagine that the overall release of pressure from the injectors working would effect that reading?...I may be wrong so correct me if i am...
Unless you have an adjustable FPR?
Unless you have an adjustable FPR?
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