No start electrical problem - 94

[rmCole]

Ok, here is what I have and what I have tried.

96 LT1 manual, 136K, just bought it several months back so I have no history. Looked around the CAC, seems it could be the VATS, but I get a low battery light...please help with ideas.

The symptoms
1. Intermittent no start, mostly cold, happened once when hot.
I put in the Key, push clutch and turn, everything lights up on the dash, no cranking, no sounds (sometimes I think I can hear a short duration whirring sound, no clicking, no smells), low battery light comes on.
2. So, I try to start it again, and again, get out and fiddle with the battery cables... Make a phone call to see if anyone is around to jump or rescue me. Walk around thinking and waiting. Try again - starts strong first time - I hope it's a fluke.

Works good for a couple of days, then happens again in the morning. Eventually it starts and I'm late to work. No jump, just starts working out of the blue, same low battery light. Then again on my way home. Happening more often, but I always get home. By now we both think it's a battery problem.

4. Read forum, get scared it's VATS. Check Volts gauge, shows good before start 12.3 and 13.9 - 14.1 when charging. Don't see any mention of low battery light connected to VATS problem.

5. Charge battery, shows a little low and takes charge, car starts good for several days - problem solved. Buy new battery, clean everything and replace. Sticker on the replaced battery showed it was only one year old so I'm still worried.

Works good for a couple of days. Then - same symptoms, low battery light, no crank. This time I don't fool with anything, just walk away, wait, and try again. Takes three times. (Maybe I didn't wait 4-5 minutes at first). Takes so long I get stuck in a traffic jam.

What's next? Would the solenoid or VATS give a low battery light?
I had some corrosion on the cables, saw one CAC forum post about checking for 0.5 volt drop as corrosion indication. I have not followed up on that yet.
Does not seem to be heat related starter problem, usually happens when it is cold.

Starter switch is a little sloppy, not likely it is recently replaced but why would starter switch give low battery light?

I only have one key, so I have not tried a different key for the VATS. Although, this last time I intentionally waited to see if something would reset - took several waits, lock/unlocks before any success.

Help
Thanks
Roger

 

[gmjunkie]

1. Check All Grounds on Chassis and Engine

2. Check Pos Cable on Starter!!

3. Check Relay behind Battery (It's about a 1 1/2 inch rectangle and has a bunch of Orange Fuse-able links on 1 side of it!!)

4. Make very sure that both battery cables are Not Corroded up inside where they attach to the Battery!!

 

[rmCole]

Thanks for the ideas, I'll have something to do this weekend.
I did clean up some corrosion, but did not yet check the other ends of the cables or the grounds. Glad your not thinking it's the VATS.

Is that you driving or in the passanger seat?

 

[John-C5]

The low battery light on the dash is really a charging indicator. With the ignition switch in run or start position the light will be on if the engine is not running, that’s normal and has nothing to do with you starting problem. If it happens again a quick way to check that it’s not the battery or POS / NEG cable would be to turn your head lights on and try to start it. If the lights go out or real dim the problems back at the battery or cables, if not it’s something in the starting circuit. It could be a VATS problem or the clutch position switch, either of these will prevent the theft deterrent relay from picking up and give you the symptoms you have.

 

[jmccloud]

No Start

Can you hear the solenoid click when the key is turned to start? If so, it's definitely not VATS. My '95 with 90k miles had symptoms like yours (could hear the solenoid click) and it was the solenoid. It's possible to repair the solenoid (not easy) so I went for a whole starter/solenoid (about $110 and less than 1 hour to replace myself). One trick to unbolt the starter is to use a 1/4" drive long extension (it's skinny) with a 1/4-3/8 adapter to the socket. That way the wrench will almost clear the cat heat shield (so I bent it 1/8").
If it turns out to be VATS, that's not really difficult to diagnose and (usually) to fix. My tumbler was sticky so I lubed it with powdered graphite. Bad mistake as graphite is conductive and changed the apparent resistance of the key. A few days later the no click - no start indicated VATS and I remembered having shot the graphite in. Fortunately there were spare foam ear plugs in the console and three or four careful 'ear' swabings cleaned the graphite out of the tumbler. Waited the 6 minutes or so for the VATS to reset and it started right up.
Hope this helps.
Come back for VATS resistances if you need them.

 

[gmjunkie]

Is that you driving or in the passanger seat?

It could be the VATS,Spray some electrical contact cleaner in the Ignition tumbler too,and make sure there is nothing on your Key Chip!!

That's my Chaffer, Flora Bright Redd my Grand Daughter!! She already has a Red Corvette,Paw,Paw will have it running by the time she can Legally drive it!! In the meantime she just practice's!! Breaker,Breaker, Ya out there Paw,Paw Junkie!!:cool

 

[rmCole]

Thanks for the help. No real noise when I try to start it. Sometimes, not every time, I can hear a faint whirring for a second or two, like a fan or maybe the fuel pump. I'll get an assisstant (like GMJunkie but not likely as cute) next time it happens to help listen under the hood.

Thanks, this is the kind of stuff you don't find in the books, but makes everything easier. I'll let you know what the fix is when it starts every time for a week or two.

Later
Roger