ecm problem 92 lt1/six speed

**cotton** · 08-26-09, 04:40 PM

have to replace ecm on my 92 vette lt1/ six speed
any toughts on direct rebuilder with good rep
any idea of time required
thanks for your help in advance

**tmkassin** · 08-26-09, 07:51 PM

There is a place in California that I sent mine to about 2 months ago. It cost $165 and is guaranteed. I willl post the contact info tomorrow as I have it at work and I am at home. It takes about a week for them to fix it and send it back. You don't pay tilll it is fixed.

**Schrade** · 08-26-09, 10:13 PM

Originally Posted by cotton

have to replace ecm on my 92 vette lt1/ six speed
any toughts on direct rebuilder with good rep
any idea of time required
thanks for your help in advance

What's wrong with your ECM? Did the leads test bad?

In case you haven't tested it, here's how:
MMMM = Mickey Mouse multi-meter.

[Me] And now we're doin' circuit by-pass INTO PCM from fuse block.

The circuit is #239 Ignition feed circuit. This circuit also controls MANY other parameters, so it is a good test to note.

I used a non-zinc paper clip to probe the PCM connector - better conductor. I also gave it an edge, instead of blunt end, to not push connector pins out of the way. Twist it as you push. I stopped just short of going all the way to the connector face, to not push the female part sideways. You might be able to see it next to the pin in the 4rth pic.

Then I tested for continuity by puttin' another clip into the front of the connector, and checkin'. It's hard to see the black MM probe I'm pinchin' there...

And the same procedure for the split-off of circuit #239 ignition feed wire. See FSM schematic here

edit: Man - this is GOOD stuff huh uh huh!

**Schrade** · 08-26-09, 10:21 PM

You'll need the FSM to identify which of the 4 ECM connectors has the right circuit.

Each ECM connector has 2 rows of 16 connectors; not all populated. The pinout identifier for each of the 4 ECM connectors is at the front of volume 2 FSM.

Then, you'll need the fuse block schematic, to see which circuits are in common with your problem circuit, to see if THOSE circuits have a problem also, like so:

If you have a short, a new ECM will NOT solve the problem.

**tmkassin** · 08-27-09, 06:15 AM

ECM repair; Call them first and they will email you a form to include when you send it. Make sure the prom is in the computer. Mine wasn't and it delayed things a week.

Python Injection Inc.
8625 Central Ave.
Stanton, CA 90680
800 959-2865

**cotton** · 08-27-09, 04:55 PM

I really appreciate response: in such a hurry to drive my
new to me vette/let a local repair facilty run the chks on the
check engine light and they came back with the ecm and also a
ebcm for the brakes that needed replacing: they said that I need to
go with the delco part and it was on back order and would not ship
untill the 28th of august did not realize would take this long and
still chance it will be later than this week so was going to look at
options from folks that have already been down this road. have read
enough now that i have ordered the complete fsm for the car and hope
to start doing my own repairs that I can handle as I am going to try
to go back to factory original on this unit never seen so much electronic
**&&^ on a car in my life.again I really appreciate your response and
hope down the road I can contribute to someone as well thanks

**Schrade** · 08-27-09, 05:24 PM

Originally Posted by cotton

I really appreciate response: in such a hurry to drive my
new to me vette/let a local repair facilty run the chks on the
check engine light and they came back with the ecm and also a
ebcm for the brakes that needed replacing: they said that I need to
go with the delco part and it was on back order and would not ship
untill the 28th of august did not realize would take this long and
still chance it will be later than this week so was going to look at
options from folks that have already been down this road. have read
enough now that i have ordered the complete fsm for the car and hope
to start doing my own repairs that I can handle as I am going to try
to go back to factory original on this unit never seen so much electronic
**&&^ on a car in my life.again I really appreciate your response and
hope down the road I can contribute to someone as well thanks

Don't pay any attention to peoples' words - words mean nothing, then the sound stops, and they mean less. Get them to show you a multimeter plugged into a connector that shows a circuit fault - like no current when there should be, or vice versa.

What codes are you getting? We can get a head start on diags till the FSM comes in...

From here...