Overfinch Chevy V8 - No Spark, No Fuel

[TANGO1]

Hi can anyone help. I have a 1989 Overfinch Range Rover with a 5.7 Litre Chevy V8 with a Tuned Port Injection system.

I used the car on Sunday and it was running like a dream. Got in the car on Thursday night turned the key and would not start. The engine turns over but there is no spark and no fuel getting through, any suggestions as to the problem would be appreciated as I am at a complete loss!

Cheers

[Trooper2]

Have you checked the fuse for the ECM?
Does Overfinch use some type of inertial cutoff switch?

Edited by Trooper2 on Friday 27th April 23:23

[boosted ls1]

Sounds like a fuse or a relay to me. Have you checked fuses and tapped a few relays?

Boosted.

[eliot]

Ive got the TPI Fuel injection swappers guide here - can scan some pages if needed.

[TANGO1]

Have checked all the fuses. Not sure which relay does what as this car is an unknown quantity.

I am presuming as the pump is priming when I turn on the ignition that the ECU is powered.

It has been suggested on another forum that it could be the ignition module, does anyone know what this looks like as it could be anywhere on this vehicle.

I have a book on TPI but nothing in there seems to help and I have been unable to get into the distributor as there is very restricted space and the need for a special tool to undo the recessed bolts.

Does anyone know a good chevy mechanic near the Salisbury area.

Thanks

[eliot]

Yes the ignition modules can fail. You remove the cap, then the rotor arm and its underneath. They are typically refered to by the number of connectors on them , 4 pin, 7 pin , 8pin etc.

Only ever worked on the old coil in cap 4 pin version, only tool required was flat-bladed screwdriver to remove the cap.

Module is About £20 from yank suppliers, like John Woolfe racing etc.

[TANGO1]

If the ignition module has failed. Would this also account for no fuel getting through.

[steve_d]

TANGO1 said:

If the ignition module has failed. Would this also account for no fuel getting through.

If the ecu is reading the ignition pulse after the amp then it would not know when to fuel.
There may not be an amp and the spark is controlled from the ecu then loss of trigger signal could also stop both spark and fuel.
Do you have the facility to plug in a laptop and see what is happening?

Steve

[TANGO1]

Thanks for your advice, we are not able to swap parts from a good vehicle to test so therefore it is going to be process of elimination.

No facility to plug into a laptop

[eliot]

If i recall correctly, They work in bypass mode during cranking - i.e. they fire at a static 10'c btdc based on the mechanical trigger point on the dizzy - so as long as it gets 12v etc, it will fire - this is also used for limp-home mode.

All this knowledge is based on what ive read about integrating them into megasquirt - photo's and decent description of how it works can be found here:

www.megamanual.com/ms2/GM_7pinHEI.htm

(you could always just upgrade it to megasquirt - then YOU CAN use a laptop and you get to fully understand all aspects of the system!)

Eliot.

[TANGO1]

Thanks for this, going on what is shown on the link you put I have now been able to establish which module I have, will order one tomorrow and hopefully this will fix the problem.

Thanks to everyone for their assistance, will let you know how I get on.

[Tazio1]

I think that you should look at the distributer as it can overheat and melt the wires and plugs. It would lead to the problem you decribe. If I am right you will need to get the plugs and wires replaced and have the distributer repositioned inside a heatproof housing, I believe that Vauhall manufacture a part for this purpose for the Astra.

Hope this helps,

Taz.

[eliot]

Tazio1 said:

I think that you should look at the distributer as it can overheat and melt the wires and plugs. It would lead to the problem you decribe. If I am right you will need to get the plugs and wires replaced and have the distributer repositioned inside a heatproof housing, I believe that Vauhall manufacture a part for this purpose for the Astra.

Hope this helps,

Taz.

new one on me
Dizzy is at the back of the engine in the middle, never seen melted wires. Although i suspect the heat does knacker the ignition module over time.

[TANGO1]

Does anyone know how to get the pickup module out. got as far as the shaft in the distributor and cant work out how to get it out.

cheers

[TANGO1]

Thanks for everyones advice. Car now running. It turned out to be the pickup module. Had to drop the engine off its mounts in order to get the distributor out to replace the module. The Overfinch idea of the 5.7 conversion for the car is wonderful but short sighted when it comes to maintenance, took 6 hours to get the distributor out and back in running.