87 928 starts but won't keep running - ideas on where to start?

After I wrote this post I did a search and found this, which is the same as John aka Stepson posted
turn the ignition on (don't try to start the engine yet), and listen very carefully for clicking from the injectors. If the injectors are clicking, the LH (injection) ECU has died.
In light of that it is up to you if you continue with any other test. personally I would check for fuel and spark, but I replaced both my computers for a stand alone Tec-4 GT system so I don't have an LH or EZK anymore

Well the first place to start when you have a problem is to do a little searching
but you can start in our 928 OC technical library link below

forums.928oc.org/vbulletin/forumdisplay.php?f=16

There you will see the first link on that page is to more links
[Links to external 928 area]

forums.928oc.org/vbulletin/showthread.php?t=995


the fifth link down [Nichols 928 tips] has lots of help

nichols.nu/tips.htm

under Engine there is a basic Diagnostics steps page that will help some


1-To short cut to check for fuel pressure, you need to listen for it running when the key is turned on, if yes?
then connect a gauge to the front of the fuel rail. do you have a test gauge?

2-To check for spark you need to remove a plug wire and install a tester or an old plug that worked.
Connect a ground wire to it and while cranking watch for spark. is there spark?

ILL wait till you get this far

928mac;9792 wrote: After I wrote this post I did a search and found this, which is the same as John aka Stepson posted
turn the ignition on (don't try to start the engine yet), and listen very carefully for clicking from the injectors. If the injectors are clicking, the LH (injection) ECU has died.
In light of that it is up to you if you continue with any other test. personally I would check for fuel and spark, but I replaced both my computers for a stand alone Tec-4 GT system so I don't have an LH or EZK anymore

Well the first place to start when you have a problem is to do a little searching
but you can start in our 928 OC technical library link below

forums.928oc.org/vbulletin/forumdisplay.php?f=16

There you will see the first link on that page is to more links
[Links to external 928 area]

forums.928oc.org/vbulletin/showthread.php?t=995


the fifth link down [Nichols 928 tips] has lots of help

nichols.nu/tips.htm

under Engine there is a basic Diagnostics steps page that will help some


1-To short cut to check for fuel pressure, you need to listen for it running when the key is turned on, if yes?
then connect a gauge to the front of the fuel rail. do you have a test gauge?

2-To check for spark you need to remove a plug wire and install a tester or an old plug that worked.
Connect a ground wire to it and while cranking watch for spark. is there spark?

ILL wait till you get this far

I've got spark but I don't have a test guage for the fuel pressure.
I'm still hearing that tick, tick, tick sound.

When you turn the key to the "on" position, does the fuel pump hum? You only have like 3 seconds to check. Have somebody turn the key for you and feel the cover to check. ....OR..... make a jumper wire for the fuel pump relay. To jumper: remove the relay and look at the orientation of the male spades. Find spade terminal 30 and terminal 87 on the relay. Move to the Central Fuse Panel and connect corresponding terminals 30 and 87. Check for fuel pump function. Remove the jumper wire (the fuel pump will continue to operate if it is presently doing so until you remove the jumper wire) so that the engine will not hydrolock from a leaky injector.

If the fuel pump works when you use the relay and turn the key, then again I say you need to test your LH unit on someone elses car.

If the fuel pump works only with the jumper wire, try starting the car. I doubt it will start, but I have had LH computers that failed (or were in the midst of failing) that failed to provide the correct ground for the fuel pump relay. BY using a jumper wire, that function was bypassed and the car ran just fine. I don't think this will happen in your case though.

Just remember to remove that jumper wire when you are done.

I've decided to send off the LH/ECM unit to have it checked.
I've taken the testing as far as I can.
I'm really glad I joined the Club. This makes owning a 928 even more fun.
I'll follow up with a post if this is the problem.

Thanks for all of the help and support.

I sent the unit off to
Specialized ECU Repair
1-800-328-1425
www.ecudoctors.com

They charged me $400.

I was very pleased with their service.

Back on the road in my 928!!!!!!!!!

Town,
Glad they got you back on the road. How did you hear about Specialized ECU? What kind of warranty did they give you? Just wondering as I have never heard of them before.