Ty

I changed out the clutch (did it myself for the first time!) and now my car won't start! When I try to start the car, the engine drags. I thought it was the battery since the car has been sitting for six months, so I had it checked at the auto parts store and they said it was okay. I had it charged (thought it might have been weak) and put it back in the car but it still dragged while cranking. Then dummy me got a battery out of my other car and when I hooked up the battery cables the car started smoking! Now my radio won't come on but everything else seems to be working fine. I hope it's just a fuse but there was alot of smoke, like a small camp fire. So then I did the right thing and got a new battery thinking the old one might have had a dead cell or something. When I put the new battery in it did the same thing!!!!!! Seems to me the car should crank because I didn't mess with the engine besides the reference sensors. Any suggestions PLEASE!!! I DON'T WANT TO GO BACK IN!

MarkRobinson

I'd say you smashed the crank trigger putting the clutch back in, but since you reported so much smoke, better hunt down that source first: probably damaged a few wires at least...one fuse poping doesn't usually cause any smoke or smell.

Ty

What does the crank trigger do and where is it located?

Ski

Just asking here, did you remove the reference/speed sensor bracket when you pulled the bell housing or just the sensors? If you removed the bracket, how did you set the speed sensor on the ring gear - are you familiar with the procedure of how to set it?

If you pulled the starter cables up from below, then I would pull them back up and look for cracking in the shielding, which could ground out from the positive cable and cause your smoke. We just did this on a car and we had to repair three spots where the wire cracked.

MarkRobinson

Crank trigger/speed reference sensor: same thing, different names. Top of the bell housing behind the motor: tells the ECU when your motor is at TDC to time the running sequences. If there's no signal, the car will not get spark (& possibly not fuel).

Mark

WesM951

Ditto on the ref sensors, thats the only thing I can think of that would cause the car not to start on a clutch job.

The smoke.. hopefully u didn't fry the DME/KLR. IIRC it says to be careful when jumping or charging. I always d/c the bat cables when I charge the battery.

Chris White

My guess is that you didn’t get a good ground and now you may have backfed through other circuits and possibly fried some electronics. (hopefully this is no the case!)

Did you reconnect the main ground from the batter to the bellhousing along with the smaller brown ground wires?

If it is the reference sending then the tach won’t ‘wiggle’ when you crank it.

Ty

Thanks for all the replies... Yes I did remove the speed / reference sensors. How do I reset them to the ring gear? I also pulled the battery connector cables up to get them out of the way of the bell housing... but I haven't inspected them to see if they have cracks. I'm keeping my fingers crossed that I haven't fried any computer electronics. The fuses in the fuse box were checked and none seem to be blown. Does anyone know if there are any fusible links anywhere that might have fried? The smaller wires where reconnected and the tack does not wiggle when I try to crank it. Then again the tach doesn't have chance enough to wiggle. The most I can get it to turn over is maybe two somtimes three times. It seems as if the battery is dead but that's not the case because it's brand new. It just drags hard while trying to crank the engine. I'll start by checking the cable grounds and let you all know if this solves the problem.

Ski, when this happened to you, did you fry any electronics and / or did you have to replace anything else afterwards to get the car running again?

Thanks,
Ty

special tool

Did you use the proper Porsche 951 specific low-clearance 12 point pressure-plate bolts?
If you didn't, you may turn the engine over little by little and grind them down - but you will need to drill them out next clutch change.
If you use 944 NA bolts, they will machine a groove into the bellhousing - but it will be difficult to start until the machining is done.

Ski

the starter cables just had some cracking in the shielding, we repaired them with insulating electrical tape.

The speed sensor, DG - the one in the back, is the one you set with a .8mm washer on an old sensor and you lock the bracket in place with the 6mm allen mounting bolts but if you did not remove the bracket and the car was running then you should be ok. BG is the front sensor and that is the reference sensor. Are the female receptacles marked, could you have crossed them? We started the car fine, as we repaired the cables before we tried to start it after the rebuild.

Mighty Shilling

FWIW, when I rebuilt the 924S, I didn't know to set the crank sensors. had em touching the flywheel. started it, it was dragging like you've described, then it ripped it off, and jammed between the bell housing and flywheel... tried turning it over again, nothing. wouldn't crank at all. starter started smoking... had no idea and towed it to the dealer... where they took it apart and looked at it...took care of it.... good luck man...

Ty

Well I checked the cables and they are fine, not unless there are some pin holes somewhere. I have a dumb question because I can't remember... There are three cable wires that run to the starter, two black (one smaller than the other) and one red and black. Are the two larger solid black ones suppose to be on the larger starter bolt or is smaller solid black one suppose to be hooked up with the red and black. I notice that the red and black and the smaller of the solid black seem to be in the same insulated casing... does anyone have a pic that I can look at?

Tom M'Guinn

As for the starter wires, read all about it here:

http://my.execpc.com/D3/79/eelfner/9...rade%20Kit.pdf

The two heavy cables go on the same lug without the little red/black wire.

As for the overall problem, I'd start by putting it in neutral and trying to turn the motor by hand using a 24mm wrench on the main pulley. If it is super hard to turn by hand, then you can be pretty sure the problem is mechanical rather than electrical.

Ty

I loosened the reference sensors (thanks porschephile 924) hoping they weren't rubbing against the flywheel and tried to turn over the engine but still had the same result. Tom, I'll try to turn the engine over by the main pulley and see if that helps. Are there any tell tell signs that the starter is going out? Would that cause the dragging?

Special Tool: I did use the proper stock bolts and torqued them to specs.

Porschephile 924, how much did they hit you up for if you don't mind me asking?

Thanks to all for your input, I greatly appreciate it!

Ty

Ski

sensors are around $110.

remove the plugs to make turning the engine over easier by hand so you don't have to overcome the compression - it should turn over pretty smooth this way if nothing is binding.