Security light/won't start
Thread Starter
Cruising
Joined: Jan 2011
Posts: 14
Likes: 0
From: Fayetteville nc
Security light/won't start
I have a 1993 c4 automatic trans. after driving around town about 15-20 min the security light flashes and the service ASR light comes on and when I cut the car off it will not start back up, it will turn strong but won't crank. I have to wait for about 15 min and it will start like nothing happen. If I try to start it before the 15 min it will at like it's going to start but seem like it's not getting a continous gas flow and cut off. It takes longer for the lights to come if driving on the HWY. Help please:
Racer
Joined: May 2007
Posts: 301
Likes: 0
From: Flint MI: Birthplace of the Corvette
Intermittents are difficult to track down. You need to have a few tools with you the next time it dies. Check for spark and fuel pressure to narrow the problem area. The security light suggests a VATS problem. However I thought VATS only affected a car while cranking not while already running. Here is a little information about how VATS works, that may give you some ideas. I'm not sure why your ASR light is coming on. Maybe someone on the forum has seen these symptoms before.
http://vats.likeabigdog.com/
http://home.hiwaay.net/~davida1/passkey.htm
Try to pinpoint the problem area before throwing parts at it. A factory shop manual is almost a necessity for solving these kinds of issues. Good luck.
Dave T.
http://vats.likeabigdog.com/
http://home.hiwaay.net/~davida1/passkey.htm
Try to pinpoint the problem area before throwing parts at it. A factory shop manual is almost a necessity for solving these kinds of issues. Good luck.
Dave T.
Instructor
Joined: Jun 2006
Posts: 195
Likes: 0
From: Canyon Country CA
Next time it won't start, try smacking the ECU (box mounter over the master cylinder area) with the palm of your hand. Mine did the same thing a couple of years ago. At first, a smack would induce a start. Replaced the ECU to resolve the problem.
Joe
Joe
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Aside from hitting it, others have put ice pacts on the ECM to get a feeling if temperature affects it. The ECM can play tricks on you flashing lights with false indications. I would see if I could read the codes when the problem is happening. You're not going to fix this with a code but what you're looking for is to see if your can communicate with it, could be a clue.
As suggested you have to make some measurements while problem is occurring. Find out if there is a healthy spark, good fuel pressure and if there are injector pulses (drive to the injectors). Without some real data you will be guessing all day and won't be able to eliminate working systems.
** Just wanted to add if a true VATS event occured, the engine would not turn over (start relay not energised). It would also disable FEDS and there would not be any drive to the injectors. If there was a pass key probelm, there may be a code set for it (51).
Last edited by pcolt94; Apr 19, 2011 at 08:55 PM.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
I think I would start with pulling the ecu connectors and spray them all down along with ecu pins with some contact cleaner checking for deformed contacts. If it does it on the way home as soon as you get home see if the ecu seems very hot. I have a 91 so no ASR but there might be a clue there with that light on at the same time. Makes me think there is a problem with various modules not communicating with each other to be honest. So it might be worth the effort to do the contact cleaning job on the VATS module and ABS assuming that is what contrls the ASR though I have no idea about that. It just seems logical in that the wheel speeds go there.
Dave
Dave
Race Director
Joined: Sep 2006
Posts: 11,199
Likes: 1,139
From: Santa Rosa Beach FL
source: GM Service Bulletin 91-384-6E
If U want to smack anything smack that author who provided bad info.
I see he ended up replacing it. Don't let it happen to you.
Sorry for the 45 day rule infringement but this needed to be corrected for any reader in the search mode. I'll request a lock now.
