Starting problem: Security?

[dakotapalm]

I have a occasional starting problem with the Bonneville that began maybe four weeks ago. Every so often, when I turn the key, the battery will do its job, the starter will begin, but the engine will not fire or turn over. The first time, I left the car in the evening (don't worry, it was in a safe place) and it started right up in the morning.
Since then, when this has happened, I've waited five to eight minutes-while making several attempts in the interim- and the car starts just fine. The car is running well, it won't die once it is started, it has just had the starting problem on occaision.

When this occurs, the engine has usually been running within the last hour; I've never had this occur when the engine is COLD.

If this were a security system problem, the security light would go on from the instrument panel, correct? Also, I've tried two different ignition keys and that makes not difference. I'm confused about this, and I don't want to burn up the starter or tax the battery too much. I've had problems with the car starting before and replaced the alternator, but this is clearly something different.

Someone suggested the security system, somebody else suggested the fuel pump; the fuel pump's been replaced a month ago... I also used a bottle of Chevron Pro-gard about a week ago. can't think of anything else related.

Again, it always ends up starting, but I want to figure out why the engine won't fire and obviously I don't want this to get worse.

Would this be related at all to water from the hood vents?

[bonnevillain]

AFAIK the security system will prevent the engine from cranking.

[crash93ssei]

AFAIK the security system will prevent the engine from cranking.

Not sure about other years, but yes, in '94 the security system will not even allow the starter to engage.

Have you checked out the ground busses and battery terminals for corrosion?

[Billha]

If 'the engine will not fire or turn over', you're saying that no cranking is occurring. If that's true, and the security light isn't on, then it could be the battery, battery connections, or the starter. If there's nothing but a click noise when it happens, then it may be the starter. If there's no click noise at all, then it may be the solenoid.

If, when it's misbehaving, you go under the front of the car and carefully but firmly tap the starter with something such as a rubber mallet and then the starter turns over the engine, then it's either a bad connection to the starter or a bad starter/solenoid.

If the secirity light is on, however, then it's a problem with the key, key contacts in the steering column, or the security system.

[dakotapalm]

Thanks for the replies. I'm still confused about this. It seems the car has the difficulty when it's been hot, sat out on pavement, and the engine has run recently. But as I said, it does start MUCH more often than it has any trouble. NEVER any trouble in the cool or in the rain.

I have checked the connections from the battery and the (ground buss is the plastic pieces under the carpet by the drivers' door, right?) recently, as I replaced the alternator about a month ago. Billha, I'll have to bring something like a rubber mallet with me- but I do hear the starter chugging when it's trying to start.

I've never actually seen the "Security" light go on... is it supposed to light up when the car starts?

[crash93ssei]

When it does this, do you hear the starter engage, but not roll the engine over? It should be a deep, somewhat loud thud / pop type of noise. If that is what you hear, chances are that the starter is bad.

[dakotapalm]

Hey, thanks for the help on this. Apparently the thing that was the problem was a "crank sensor," which I had never heard of before. The odd thing was that it would work perfectly sometimes and not others. The shop I took it to ( kinda had to after I was marooned 25 miles away and had to hitch a ride) replaced it on a guess, but the computer didn't have any information. Thanks again.