85' won't start - ECM?
Thread Starter
5th Gear
Joined: Mar 2003
Posts: 5
Likes: 0
From: Charlotte NC
85' won't start - ECM?
First -Thanks for all the troubleshooting tips I've seen in related postings.
After changing my battery a couple of weeks ago my 85' won't start. The car is at 198,400 mi. and I'd like to celebrate 200 w/her. I've changed the fuel pump, filter and relay with no results. I've pulled some plugs and given a crank and confirmed that I am still getting spark. Then I pulled the fuel-in line from the rail, shorted the relay and confirmed that fuel is at least getting to the rail.
My question is - IF my ECM was bad could it be preventing fuel from passing from rail to chamber? What simple test can I do (no scanner) to confirm whether the ECM is bad or not?
After changing my battery a couple of weeks ago my 85' won't start. The car is at 198,400 mi. and I'd like to celebrate 200 w/her. I've changed the fuel pump, filter and relay with no results. I've pulled some plugs and given a crank and confirmed that I am still getting spark. Then I pulled the fuel-in line from the rail, shorted the relay and confirmed that fuel is at least getting to the rail.
My question is - IF my ECM was bad could it be preventing fuel from passing from rail to chamber? What simple test can I do (no scanner) to confirm whether the ECM is bad or not?
Racer
Joined: Dec 2003
Posts: 378
Likes: 0
I had the same problem with my '88 a few months back, except the idiots at the shop down the street told me it was the injectors and wanted $800 dollars to replace and install them. My problem did end up being ECM, and yours sounds very similar to the symptoms that mine was having. It had gone bad and fried itself somehow, probably from me changing out the injectors. So what you need to do is take it up to a shop where they've got a big machine that hooks up to your computer and that can tell you exactly whats wrong with it. That's my guess. Best of Luck! IM me if you have anymore questions regarding this matter.
P.S. A rebuilt ECM cost me about $200.
P.S. A rebuilt ECM cost me about $200.
Drifting
Joined: Mar 1999
Posts: 1,931
Likes: 1
From: Norcross GA
The FP isn't even sending the "prime" signal?
Do you get a SES light?
Easiest way will be to try and borrow someone's scanner.
Other things to check:
ECM fuse
Both Inj fuses (Sometimes labled ECM1/2)
Are the ECM conn's properly seated?
If your not even getting the FP to prime,... It can be the pwr or gnd connections to the ECM. i.e. Check the Pwr & Gnd at the ECM conn or ECM pin itself.
Do you get a SES light?
Easiest way will be to try and borrow someone's scanner.
Other things to check:
ECM fuse
Both Inj fuses (Sometimes labled ECM1/2)
Are the ECM conn's properly seated?
If your not even getting the FP to prime,... It can be the pwr or gnd connections to the ECM. i.e. Check the Pwr & Gnd at the ECM conn or ECM pin itself.
Thread Starter
5th Gear
Joined: Mar 2003
Posts: 5
Likes: 0
From: Charlotte NC
Originally Posted by ZylaRace
The FP isn't even sending the "prime" signal?
Do you get a SES light?
Easiest way will be to try and borrow someone's scanner.
Other things to check:
ECM fuse
Both Inj fuses (Sometimes labled ECM1/2)
Are the ECM conn's properly seated?
If your not even getting the FP to prime,... It can be the pwr or gnd connections to the ECM. i.e. Check the Pwr & Gnd at the ECM conn or ECM pin itself.
Do you get a SES light?
Easiest way will be to try and borrow someone's scanner.
Other things to check:
ECM fuse
Both Inj fuses (Sometimes labled ECM1/2)
Are the ECM conn's properly seated?
If your not even getting the FP to prime,... It can be the pwr or gnd connections to the ECM. i.e. Check the Pwr & Gnd at the ECM conn or ECM pin itself.
Advanced
Joined: Dec 2003
Posts: 75
Likes: 0
From: Lenexa KS
Originally Posted by Dhericb
I'm gonna run out to the garage and scrounge for the ECM in a few. I looked for it in that mass or wires under the steering column last night but didn't get far by flashlight.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
You need to put a fuel pressure gauge on the shrader valve on the end of the fuel rail and see if you have the correct fuel pressure. Next, remove a plug from one of your injectors and connect a low power 12v lamp across the plug and crank the engine. The lamp should pulse when cranking, showing that the ECM is pulsing the injectors. No pulse , no fuel, no start.
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