Starting Problem - sometimes starts, sometimes not

blownsc

Registered User
I think i've read almost every post regarding bad starts but I still can't pin this problem down. Firts off, I just got my 90sc (manual) back from an engine rebuild. When I try and start it, the starter works and turns the motor over every time, but it does it slowly and makes the typical "your battery is dead" werrrwerrrwerrr starting sound. I just replaced the battery w/ a red top and it's no better. It will fire up about 1/2 the times I try to start it (still cranks slowly though). The other half the starter turns and the engine turns slowly over, but no fire. I arc'd the starter relay (between the 2 big bolts) on the fender wall and the starter engaged (still slowly and fires 1/2 the time as before). I also applied direct 12v from the battery to the relay lead going to the starter and the little ignition switch terminal on the relay. Both times, same result as before. I took it down to kragen and they hooked up their tester to it and I ran through the rev/idle/rev testing procedure w/ it hooked up. The guy told me my battery and starter were fine. Could it really test the starter w/ it on the car? I first thought cam sensor and replaced that tonight, but it did not help. Also, My lights (interior/ stereo) dim a little (not really too noticable) when starting. If I start w/ my headlight on, the headlight dim a lot. The upshift light is on sometimes while it tries to start and othertimes not (not sure if this is normal). The car runs perfect once it starts up. The crank sensor was replaced about 5k miles before it went to the shop, not sure if that's the cause. I'm going to get under it tonight and try to check all the starter side connections. Can I abble direct 12v from a jumper to the starter to test for a connection problem?
I know u guys are the best and will figure this one out too.
Thanks,
Kyle
 
after further reading, it looks more and more like cps. autoparts.com has 2 available
Niehoff Ignition FF440H $45
GP Sorensen CSS15 $78

Anyone used the cheeper of the two?
I'm going to try to clean the old one and re-check it's wiring and alignment in the morning. I allready replaced the HB and cps before the rebuild so I hope it's not bad allready..
Let me know what you think anyways.
Kyle
 
Before you go spend 1 more $ on the problem

Try this: get in, key-on, clutch in, engage starter and hold until the engine starts.
If for some reason, you should let off and the starter stops, turn the key completely off before trying it again.

I would say, hope this helps, but I know it will help ;) ;)

If your cps were bad, the engine would not run at all.
 
there were little bits of metal stuck to the magnet on the cps. might have caused bad readings. Also, the 2nd connector for (the small 1 wire square one) came right out when i pulled it a bit. I think it's just a ground that reduces interference in the shielded line, but I don't know for sure and i'm not sure it's necessary. I think i'm going to take apart the wraped wire and put it back in before putting it all back together. Anyone know for sure what this single wire w/ square connector on the cps does and where it goes/is routed so i can properly reconnect it?
I can turn the key as long as I want, it will eventually turn over so slow there is not hope of firing. THEN i can turn to off and try again, and sometime's it'll turn slow and fire right up. A picture of the cps all put together would be helpful, all the partstore pics are too small.
Thanks,
Kyle
 
-update-
cleaned and re-assembled crank sensor. Now it starts every time :) but still cranks over real slowly w/ werrrwerrrrwerrrr sound. I would guess it's the starter at this point. Going to inspect all it's wiring now and apply direct current to it and see what happens.
Kyle
 
You should be able to take the battery in to any parts store and have it tested before fooling with the starter. Oh... be sure you clean the battery posts and clamps with steel wool even if they already look clean and tighten securely. Not overly tight, just secure.
 
battery is new, got it Tuesday. Just checked, cleaned and tightened all the wiring on the starter. No difference. Interior lights dim when starter is cranking. I read a post that that means the starter is drawing too much juice from the battery and is a sign that it is dying. Read the first post, kragen tested the battery allready.
Kyle
 
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Sounds like you are on the right track. Some parts places can test your starter also. From the sound of the problem, sounds like the rotor windings have shorted. That isn't realistically fixable, unlike replacing the brushes for example. Try to avoid a rebuilt one unless you have no choice.. you might even be better off with a used one. Oh, and before you disconnect it, pull the negative battery cable off. There is a constant 12V at the starter terminals and a slight slip of the wrench will result in a spark show. :eek:
 
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