1987 no start.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
1987 no start.
Hi Guys, where are the brilliant minds? Car just decided it didn't want to start.Turns over fine,got spark,47psi fuel pressure but injectors not grounding out. squirt of easystart and she'll go so obviously it's an injector problem.Question is,has the ECM gone bad on me? Some local shop said it could be the ignition module but I don't think that would stop the injectors from firing,or could it? The only code showing is a 46-vats problem but that's because I bypassed it years ago. Anyway,anyone got any ideas?Don't want to spring for a new ecm if it's something else.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
Hi Guys, where are the brilliant minds? Car just decided it didn't want to start.Turns over fine,got spark,47psi fuel pressure but injectors not grounding out. squirt of easystart and she'll go so obviously it's an injector problem.Question is,has the ECM gone bad on me? Some local shop said it could be the ignition module but I don't think that would stop the injectors from firing,or could it? The only code showing is a 46-vats problem but that's because I bypassed it years ago. Anyway,anyone got any ideas?Don't want to spring for a new ecm if it's something else.
there are experts on here, no question. give 'em time.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
Hi Guys, where are the brilliant minds? Car just decided it didn't want to start.Turns over fine,got spark,47psi fuel pressure but injectors not grounding out. squirt of easystart and she'll go so obviously it's an injector problem.Question is,has the ECM gone bad on me? Some local shop said it could be the ignition module but I don't think that would stop the injectors from firing,or could it? The only code showing is a 46-vats problem but that's because I bypassed it years ago. Anyway,anyone got any ideas?Don't want to spring for a new ecm if it's something else.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
no start
Quits as soon as the ether is gone.I've put a noid light on several of the injectors and they don't flash when I crank the engine. There is always a 12volt pos to the injectors and the ECM grounds them to fire them.For some reason mine aren't grounding. Anyone know if a bad prom could do this?
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
These help at all? (Chart A3 page 2 from FSM)
http://i1116.photobucket.com/albums/...s/6e3-A-16.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-17.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-16.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-17.jpg
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
These help at all? (Chart A3 page 2 from FSM)
http://i1116.photobucket.com/albums/...s/6e3-A-16.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-17.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-16.jpg
http://i1116.photobucket.com/albums/...s/6e3-A-17.jpg
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
You're welcome.
Reading through note 3 on page 16, I wonder whether the fact the problem is intermittant implies a short to power or loose pins in the connectors?
I speculate an ECM problem (with no moving parts) would be less likely to be intermittant than a wiring fault.
Just a thought---I have no experience actually working on this.
Reading through note 3 on page 16, I wonder whether the fact the problem is intermittant implies a short to power or loose pins in the connectors?
I speculate an ECM problem (with no moving parts) would be less likely to be intermittant than a wiring fault.
Just a thought---I have no experience actually working on this.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
You're welcome.
Reading through note 3 on page 16, I wonder whether the fact the problem is intermittant implies a short to power or loose pins in the connectors?
I speculate an ECM problem (with no moving parts) would be less likely to be intermittant than a wiring fault.
Just a thought---I have no experience actually working on this.
Reading through note 3 on page 16, I wonder whether the fact the problem is intermittant implies a short to power or loose pins in the connectors?
I speculate an ECM problem (with no moving parts) would be less likely to be intermittant than a wiring fault.
Just a thought---I have no experience actually working on this.
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Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
When it won't start. THAT is the time you start diagnosing where the problem is. The ECM requires reference pulses from the distributor in order to pulse the injectors. See if you have pulses on the purple/white wire out of the distributor during cranking. If you don't, then you need to find out if the spark module inside the distributor is good and also if the pickup coil is good. Some parts places can test the spark module, although a member here says their test isn't reliable. You check the pickup coil with an ohmeter. I'll look and see if I can find the correct resistance you should measure. Of course, intermittent problems are the hardest of all to find!
Team Owner
Joined: Jan 2003
Posts: 20,292
Likes: 239
From: Summerland B.C. Canada
Ignition module supplies reference signal to ECM. If it's not there, no injector pulse.
Normal, 12v will go through injector coil to neg side, until the ECM supplies ground.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
Well,it seems my ECM is shot after talking to the guru at Zip.And yes,a bad ignition module could cause the problem but there's a simple test I didn't know about so I'll pass it on for what it's worth.Watch the tach when you crank the motor.If the module is good it should show 200/300 rpm when you crank.No rpm= bad module.. $109 exchange for the ECM so not too bad. Thanks for the suggestions guys.
