PDA

View Full Version : Help needed! Car won't start!



Sampo
07-13-2006, 03:07 AM
My friend's '90 SC won't start at all. He has changed DIS, coil and that crankcase thing which tells what is the "situation" of the crankcase... ( Sorry, I can't remember the real name of it...:o )

But after all that the car won't start. The fuel pump should be ok. At least there's fuel coming...

What would be the next thing to look? Any ideas?!

ThunderDave
07-13-2006, 06:52 AM
Hey Sami, that's the crank sensor. ;) What about the cam sensor? Is it good? Did he have any symptoms of a problem, or did it just all of a sudden not crank one day? The balancer could be bad too. Has that been checked yet to see if it's loose, the bolt broke or it wobbles while cranking it over?

Does he have a scanner to see if there are any codes?

Sampo
07-13-2006, 01:26 PM
Yes, the crank sensor, of course...:cool:

Is it possible that car won't start if the balancer failed? Shouldn't it start but run very bad?

My friend was driving about 45mph when shifting to 4th gear and suddenly everything shut down. Motor stopped running and he had to pull away. After that car hasn't started. I just thought if that make any help...:o

We pulled the codes but there wasn't anything special...

And thanks for the answer, RadiumSC! :)

AnnivSpeCpe
07-13-2006, 01:57 PM
Sampo, sudden total shutdown while driving most certainly points to the harmonic balancer failing. Check for broken/missing center bolt that holds it onto the crankshaft snout. If he's lucky he just broke the bolt and the balancer backed off losing contact with the sensor. More likely the balancer is broken forward of where the key indexes it on the shaft and it just spins independently of crankshaft. This is a very common problem because the balancer is designed way too weak to support the heavy double pulley and rotating dynamics of all the stuff it turns. BTW, it's just my theory, but I think 5 speed cars are harder on the balancers than automatics because of the way they are driven and the tendency to load/unload suddenly when shifting. Take off the serpentine and blower belts and the balancer may just rotate around. Good luck, John
edit: If the bolt is broken or missing avoid the temptation to just replace the bolt and re-use that balancer. It WILL fail again.

Jogi
07-13-2006, 02:10 PM
Yes, the crank sensor, of course...:cool:

Is it possible that car won't start if the balancer failed? Shouldn't it start but run very bad?

Yes it is possible to car not to start when bad balancer starts rotating around crank. Basicly it retards timing so much that engine wont starts. I went through almost all diagnostics to find out what went broken. It was balancer, but it bugged me couple of weeks before it went that bad that it did not start anymore.

- Does it light upshift light when trying to start? (orange light "up arrow")
- Try unplucking cam sensor and start then.. applies to many other sensors too, if you unplug them one of the time computer tries to function without it -> at least broken sensor does not send wrong information.
- check with timing light if you get spark when starting engine

When my balancer went broke, computer didn't gave any codes.

Anyway, even though I bable about balancer, I'm not sure is you friend have it broken.. but it is still one possibility..

You should eyeball the balancer under car and watch if there are any cracks and after that manual testing:

To test it strip balancer pulley belts and prevent engine crank rotating (manual car -> put it to gear 4 or 5) Grab crank pulley and try to rotate it in both directions. Even if balancer is broken sometimes you can't rotate it by hands so final test is to try rotate it by crank bolt (22mm?) But be careful and do not broke the bolt..

ThunderDave
07-13-2006, 02:17 PM
Yeah, chances are if it just suddenly quit running that way, it's balancer related.

Sampo
07-13-2006, 04:22 PM
Thanks for all for replying! :)

I didn't think about the balancer... Lucky me I have changed it to my car!

I will let you know was it the balancer...

Thanks once again guys!

Sampo
07-14-2006, 03:41 PM
And most likely it was the balancer! ;)

My friend took the old one away and it was broken.

Thanks for help! :)