Starting problem with my '87.

[dr3283]

Thanks again wwood.
My problem is somewhat similar but I don't think it meets either the tamper or fail criteria. Let me take a few minutes of your time to explain. When this first occurred, the car would not crank.....everything else appeared fine, just wouldn't crank. I read the GM book and waited the 4 minutes. Still nothing. When it still wouldn't crank the next day, I went to the GM dealer and had them check the key. It was a Number 10 (exactly 3740 ohms). I went ahead and had a new key cut ($36) and tried it again......no difference. By this time the battery was dead so I recharged it. The next day, the car started just fine.
For several more days it started fine, then without warning it suddenly wouldn't crank again. I went to this web site and began to follow the advice of vigman. I checked the reading across the two white wires in the crank position match the ohms reading on the key almost exactly.....jiggling the ignition didn't cause any change. After chasing down several other things, vigman had me check the starter enable relay. I could bypass it and the car cranked....so I replaced the starter enable relay. Problem solved. The car has started without fail everytime for 5 - 6 days now.
EXCEPT.......
for the SECURITY light on the DIC. According to the manual, it should flash until the system is armed, then come on steady to indicate it is armed, then go off after an interval. It also should go off when the car is unlocked with the key, then flash until the key is put in the run position.
Here's my problem. If the system is not armed, it flashes constantly. If I lock the doors, it comes on steady and never goes off. If I unlock the doors, it begins to flash again until I start the car. If I simply turn the system off but don't start the car, the light flashes continually. I could deal with this except that this seems to drain the battery every two days.
Even though the descripton of the problem described in the url you sent sounds similar to mine, it doesn't appear to be the same. Thats why I'm gonna try and replace the UTD and see if that fixes it. My reason I'm focusing on that module primarily is that when I pull the fuse, the light finally goes out.....so I'm "guessing" the two may be linked. It may be a shot in the dark but I've been dealing with this for several weeks now without much headway so its time to try something.
Thanks again for all your input.

 

[wwood]

According to my 1988 shop manual, in all the diagnosis scenarios I could find (some similar to your's, some different), the Theft Deterent Controller is causing the problem.

The manual says replace it. It looks like it will be a pain to get at. I have never taken off the RHS of the dash. If you do replace it yourself, it would be interesting to know how to access behind the RHS of the dash. Good luck.

 

[dr3283]

I appreciate you checking that out.....I have a shop manual for my 95 but don't have one for the 87 and they are considerably different. I've never had the right side dach open either but I have pulled the top of the dash itself before so I know I can go that way if I have too. But that brings up a point. The diagram someone sent me shows the UTD is in the center part of the dash and the VATS module is in the right side of the dash. I'm not sure what year the diagram was from but if your shop manual for an 88 shows the UTD to be in the right side dash, I'll have to figure out how to get in there.
(I am trying to buy a 87 shop manual but they're kinda like GOLD. I was outbid on Ebay yesterday and I stopped at $50 for a used Prelim. The originals come up very seldom. When I checked the website from GM's supplier, they're up to $75 now but on backorder. So I'm still checking.)
As I said, I've purchased a UTD thinking thats the culprit. The car is continuing to start but still draining the battery. If this doesn't work, my next option is to replace the VATS module.
Thanks again.

 

[dr3283]

New info.....I still haven't received my UTD to replace but because my car has continued to start with no problems for about a week, I thought I'd go ahead and put it back together and get it out of the garage for awhile. Sooooooo, I put the fuse back in the Theft slot behind the DIC. As I fully expected, the security light resumed its constant flashing but then when I tried to start the car......bingo.......same old "intermittent start problem".....everything lights up but the starter won't spin.
I checked the wires at the bottom of the column again and they match the key. I also checked the new "starter enable relay" and it clicks when I follow Vigman's directions......so its still good.

Based on this, does anyone know if I'm right in guessing the UTD module is the culprit???????????

Thanks.

 

[wwood]

I think I've managed to solve my starting problem.

I noticed yesterday, at an autocross no less, that one time when I put my key in the ignition it did not quite go in as it usually did. No big problem, slight readjustment and in it goes. However, no start with all the previously mentioned symptoms. It was also raining a bit ,which I previously suspected as a contributing cause. I had not locked my doors so I knew that the door key/switch problem was not the cause.

I tried the usual things which have worked for me and others, no go. Then I remembered reading that sometimes when a key goes in, if the resistance is not read properly, even though later the key/resistance is correct that the system will think that someone is tring to seal the car. They call this a "false start". When this happens the system will not let the car start, even if everything is OK, for about 4 minutes or so. If you try to start your car in the 4 minute period, guess what, the time delay starts all over againg.

Forcing myself not to try to start the car too soon I removed the key and walked away. About 6 minutes later I came back, it started instantly and all was fine.

Hopefully some of you will be as lucky with your starting problem.:Twist

 

[Tonylong]

You do't say if your car is auto or manual shift.
I have an '89auto and a similar problem turned out to be the "park/neutral"
switch. Try to see if it will start when placed in Neutral,
or hold the key in the start position with one hand, and "rack" the shifter thru the range of positions.
LOL

 

[dr3283]

Thanks for your info tonylong......however....to make a long story short, I've been on this site for several weeks now with this problem. The car I'm having a problem with is a 87 Ragtop auto.
I've checked the neutral/park switch in both positions several times and it works great. I've had new keys cut. I've replaced the starter enable relay when vigman stepped me through a whole series of diagnostic tests and it seemed to be causing a problem. This resulted in the car starting for about 5 - 6 days in a row....so long as I didn't put the fuse back in for the UTD (fuse is behind the DIC). If I put it back in (so I can lock and unlock the doors with the remote, the lite flashes all the time (all nite) until I set the Theft system by locking the doors....then the lite never goes off. The only time the light is off is when the car is actually running. I've also check the starter as well as the VATS system (code on the 2 wires at the bottom of the steering column match both keys exactly). I've ordered a replacement UTD module thinking this is causing the flaky lite (which runs the battery down).
Guess I made a mistake of trying to put the fuse back in last night because it failed to start after that. I jerked the fuse back out and it still won't crank.
I guess I'm stuck until the UTD module arrives and I can try that.
Never experienced anything at all like this with any of my others. This is enough to drive ya to drink!

 

[dr3283]

Need some help!!!!
I've got a UTD module to put it mine and see if it fixes the problem. It is located behind the right side of the dash. So far I've pulled the dashtop, the DIC panel, etc but I still haven't located the way to pull the right side bottom of the dash (the carpet piece) so I can get to the screws to release the big dash pad.
I've looked at the books I've got and they don't show anything. I've got a Shop Manual coming but won't see it for several days.
Can anyone explain how to get it off?

 

[ghfun]

Intermittent no start 96 fixed

The problem was the key cylinder had become worn (with only 29K miles) enough to cause the VATS system to not properly and consistently recognize the resistance in the key pellet. $330 at the dealer.

Thank you to all who responded. I found the TSR from another web site that detailed the problem with the key cylinder, but this forum always has so many great people sharing their experiences. I hope my last posts on how I found and fixed the Climate Control only blowing on the floor problem, helped some of you avoid the several hundred dollar mistake.

 

[Tonylong]

Maybe this would be a good time to install one of the $50 gizmos that let you
selectively bypass the vats. I did it to mine because I figured that I would be the most likely one to be stopped by the vats !

 

[ghfun]

VATS problem

That's a good idea. I have a remote starter that I have not installed yet and I was wishing I had already installed it as it effectively bypasses the VATS to enable it to start the car without the key.