Wedge in distress
Discussion
Hi. Not sure how to copy thread across to here!! Originally posted on wrong section as not used Pistonheads much before and forgot was specific section! What a numpty!! Anyway having checked last night plugs were sparking but bone dry after cranking so believe is fuel problem. Plenty of fuel in tank, probably the most it has had for ages. Checked fuel pump fuse - 20A - fine. Checked obvious under bonnet connections and can't see anything amiss so fuel pump/relay appears to be next for investigation? Where are they? Really must get a copy of the 'Wedge Bible' sooner rather than later!! Thanks for your help so far, Craig.
You can check for fuel pressure and injector operation by removing the cold-start injector from the top of the plenum, leave it connected to the wires and fuel but point the business end into a jar.
Crank the engine over and you should see some fuel in the jar from the injector. This indicates that there is some fuel pressure and that the injectors are being fired.
Warning - whatever you do don't fire the injector at your hand or flesh because the high pressure spray can get pretty painful.
Crank the engine over and you should see some fuel in the jar from the injector. This indicates that there is some fuel pressure and that the injectors are being fired.
Warning - whatever you do don't fire the injector at your hand or flesh because the high pressure spray can get pretty painful.
RussWood said:
Crank the engine over and you should see some fuel in the jar from the injector. This indicates that there is some fuel pressure and that the injectors are being fired.
Not quite true, the cold start injector is fired by the thermotime switch, not the ECU (which does fire the main injectors of course) - just because the CSI fires doesn't mean the injection will work. It will as you say prove you have ful rail pressure.The other issue is that unless it's really cold, the CSI may not fire anyway
That said, there is usually enough fuel from the CSI when it does fire to help the engine attempt to start: if it splutters and coughs whilst cranking but won't catch and run, that's a sign that the CSI is injecting but the main injectors aren't.
No smell of fuel atall. When I put the car away on sunday was running perfectly having just done about 30 miles. I did move stuff round in the boot including the targa panel etc the other day. Could I have knocked something that affects pump/fuel supply etc? Will try and have another look tonight!!
Had an issue like that and resoldering the ECU did the trick. Was able to borrow a spare ECU and this test showed the original was faulty.
This is sort of the worst case. Before that it is useful to check the connector of the ECU, and as it is a flapper if the resistor pack on one of the wings under the bonnet: the connectors can be cleaned and check if properly plugged in.
With no fuel the notorious temperature sensor seems to be out of the equation.
If checked for sparks this should be fine to get it up and running. Why, as mentioned before, leads, coil and ignition amplifier are crucial.
Remains: fuel pump failure or swirlpot/filter blocked. Could be the fuel pressure regulator, but these normally do not fail.....
As always if you find the problem, afterwards it is probably something simple as these are relatively simple cars.
Rob
This is sort of the worst case. Before that it is useful to check the connector of the ECU, and as it is a flapper if the resistor pack on one of the wings under the bonnet: the connectors can be cleaned and check if properly plugged in.
With no fuel the notorious temperature sensor seems to be out of the equation.
If checked for sparks this should be fine to get it up and running. Why, as mentioned before, leads, coil and ignition amplifier are crucial.
Remains: fuel pump failure or swirlpot/filter blocked. Could be the fuel pressure regulator, but these normally do not fail.....
As always if you find the problem, afterwards it is probably something simple as these are relatively simple cars.
Rob
Astwood Autos said:
Numpty question I know but hopefully got time have a look at wedge tonight and wanted to check fuel pump relay. Where is it? Really must get copy of the 'bible ' soon and get this car sorted! Many thanks, Craig.
It's with the rest of the relays on the relay board. 
You'll probably find it up in the passenger footwell, hiding behind a swing-down panel...
Finally got to have a look tonight. Got my daughter to crank engine but couldn't hear pump running. Took off fuel pipe from fuel pump at filter end - no fuel. Powered up pump from my booster pack and can hear it running but still no fuel. Reverse polarity on pump - nothing happens. Wiring to pump is black wire from loom to one side of pump, yellow wire from loom to other side of pump (nearest filter). There is a black wire connected to spade terminal with yellow wire but this goes nowhere, broken off from somewhere? There is a separate earth wire from pump mounting bracket to the pump. Pipe from swirlpot to pump obviously not been disturbed in ages as jubilee clips seized solid!! Decided not to mess for time being as didn't particularly want to waste well over half a tank of fuel if clips gave up!! Presuming flow from tank is okay then it looks like the pump is knackered imho. At least have made some progress!!
Thanks for that Mike. Was difficult to see underneath car as not got my trolley jack at home and wasn't jacking up very far on the crappy jack I had found!! Typical!! I have access to proper workshop facilities including a ramp and kept the car there when I originally bought it!! Once had made room in my garage brought it home!!
Finally got to have proper look at wedge this afternoon. Got my trolley jack and axle stands to get it in air and actually see what I was doing!! Bonus!! Fuel pump is mullered!! Also needs new pipe from swirlpot to pump as cracking up. Jubilee clips didn't want to shift as been there a little while by looks of things. Looks like braided hose? Is it easy to obtain? Flow from swirlpot was fine so presume that is okay. Looks like would be a good idea to put another filter between swirlpot and pump to prevent trashing new pump? Will replace normal filter as matter of course. The pipe from filter to engine bay appears to have rubber hose either end but green plastic (original?) for the main length under car. Is this correct or has someone replaced each end with rubber hose? Many thanks, Craig.
Found my old thread, save hijacking another one!! Still after some advice how to get wedge running please. Have changed pump/pipes and checked wiring. Had done this last year but still wouldn't run and not touched it again till yesterday as just not had time!! Decided really must crack this so myself and friend were out there in the frost last night till gone midnight!! Made some progress as follows.
The switch in the glovebox appears to do nothing in either position!
Pump fuse is okay. When cranking no power to pump but using power probe to fuse pump will run so know that is okay. Have tried changing relay (using window motor one) but no joy. Relay took out had Bosch part number so is it a special one? I knew there was an alarm fitted which PO said didn't work. As we could hear a relay type regular click under dash we investigated and found it was coming from alarm box. Managed to get fob to work and arm/disarm alarm but still no good. Alarm was a 1990 system consisting of about 3 boxes including a pager system, movement sensors etc. State of the art back then I suppose? Appeared to be faulty so we decided to remove it. How many Scotchlok connectors can one person use to fit an alarm? We took out over 20 connections! What a bodged mass of spaghetti!! Lot more space under the dash now!! After all that still didn't run, won't even fire!! Was gone midnight by then and we couldn't feel our feet anymore so thought should call it a day!!
Presumably power to pump goes through relay before fuse, meaning that when we power pump up doesn't necessarily mean relay is working? Need to check AFM next I think as all underbonnet connections seem okay?
Apologies for long post but any advice would be much appreciated. Many thanks.
The switch in the glovebox appears to do nothing in either position!
Pump fuse is okay. When cranking no power to pump but using power probe to fuse pump will run so know that is okay. Have tried changing relay (using window motor one) but no joy. Relay took out had Bosch part number so is it a special one? I knew there was an alarm fitted which PO said didn't work. As we could hear a relay type regular click under dash we investigated and found it was coming from alarm box. Managed to get fob to work and arm/disarm alarm but still no good. Alarm was a 1990 system consisting of about 3 boxes including a pager system, movement sensors etc. State of the art back then I suppose? Appeared to be faulty so we decided to remove it. How many Scotchlok connectors can one person use to fit an alarm? We took out over 20 connections! What a bodged mass of spaghetti!! Lot more space under the dash now!! After all that still didn't run, won't even fire!! Was gone midnight by then and we couldn't feel our feet anymore so thought should call it a day!!
Presumably power to pump goes through relay before fuse, meaning that when we power pump up doesn't necessarily mean relay is working? Need to check AFM next I think as all underbonnet connections seem okay?
Apologies for long post but any advice would be much appreciated. Many thanks.
Whoever invented Scotchloks should be shot, and anyone using them for an application like an alarm/ immobiliser should have their goolies jammed in a vice.
It's so hard to diagnose faults by remote control. There's plenty of info on the 'net to help you test individual components but when you have no idea what savagery may have been performed on the wiring that joint them all together it can be an uphill struggle.
On the RV8 the injection loom is more or less separate from the rest of the car so if you can verify that there are no spurious loops or add-ons (which it sounds like you largely have) then you're halfway there. There are only really three necessary connections to the rest of the car's electrics; anything else is suspect.
In essence, the fuel pump should run with the ignition on and the flap in the AFM moved more than about 2mm.
If not, test the AFM switch. If that's OK and linking out the fuel pump relay makes the pump run, the red steering module might have popped or be plugged into the wrong socket.
To be continued, the boss just walked in...
It's so hard to diagnose faults by remote control. There's plenty of info on the 'net to help you test individual components but when you have no idea what savagery may have been performed on the wiring that joint them all together it can be an uphill struggle.
On the RV8 the injection loom is more or less separate from the rest of the car so if you can verify that there are no spurious loops or add-ons (which it sounds like you largely have) then you're halfway there. There are only really three necessary connections to the rest of the car's electrics; anything else is suspect.
In essence, the fuel pump should run with the ignition on and the flap in the AFM moved more than about 2mm.
If not, test the AFM switch. If that's OK and linking out the fuel pump relay makes the pump run, the red steering module might have popped or be plugged into the wrong socket.
To be continued, the boss just walked in...
Further to fuelling problems we never really found the real problem. Have checked various parts of the loom as it appeared that the problem was in the section of loom from bulkhead across back of engine but fault has not replicated itself since. Car appears to be running well although always in back of your mind it may stop!! Does appear to run bit warm on the gauge though! 90 degrees most of time but soon creeping towards the red in traffic, cooling fan helps but does seem bit marginal. I did drain some coolant off and added two litres fresh antifreeze a few weeks ago. Going to try flushing system through properly as next step as car has been stood around for some years previous to my ownership. Will get there in the end. Hope to be at the Wedgefest if can get it sorted in time!! Cheers!1
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