'84 Porsche 928S Clutch Problems
Hello, I recently purchased a 1984 928S 5 speed. A few days ago, what I believe to be the throwout bearing started to make a rattling noise when I pushed the clutch pedal. When I drove it today it began squealing loudly, and then something broke and my car stalled. The clutch doesn't release now, and the pedal goes to the floor, but doesn't spring back unless pulled on.
Car still runs fine in neutral, it's just the clutch is stuck in the engaged position. Is the throwout bearing broken, or is it something else?
Did you ever resolve this? I think my car may have the same problem :/
Yes, the clutch/throwout bearing were on their way out (and i think the clutch wasn't bled properly as well). When I went to engage the clutch, the slave cylinder pushrod popped off the clutch fork, causing the clutch to engage and stall the engine. Upon removal of the clutch, I determined that the throwout bearing siezed and chewed up the pressure plate (that was the source of the noise: metal on metal because the t/o bearing wasn't spinning). Let me know if you need any tips if you replace the clutch yourself, there are several tricks that make the process a bit easier. I also have some pictures if you are interested.
Sound expensive! :D On your elaborated desciption, I think it may not be excactly the same problem. Mine doesn't make any wierd noises, it just doesn't fully open, thus the gearlever cannot be moved when the motor is running. It also feels soft and squshy, and doesn't pop back all the way, only half. It all started the day after a "spirited" drive with a lot of weight in the car (4 people). The car was fine during the sunday drive, all day, and also when I put it in the garage at night. But the following morning, it was wrong. I don't know how these cars manage to break untouched.. I have a sneaky suspision, clutch fluid may have leaked out. The car has practically been standing since 2003, so maybe the pipes are corroded.
Yes, the 928 clutches can be expensive, around $1800 if you need to replace the intermediate plate (on earlier cars) and flywheel as well! Luckily I just needed a clutch kit ($700) and was able to get the flywheel and intermediate plate machined for $85. As far as your car is concerned, it looks like the clutch is not disengaging fully. That could definitely be caused by the hydraulic system. Check the master and slave cylinder for leaks, as well as the condition of the steel clutch hydraulic lines and the hi-pressure hose. The hi-pressure hose is notorious for failing; if it is not obviously broken or leaking, have someone step on the clutch pedal when you are under the car, and see if it swells. It definitely sounds like a leak or air issue if the pedal feels squishy and doesn't return properly. Another cause could be an internally leaking master cylinder, which may not be obvious from the outside. If the internal seals are gone, you will not be able to build enough pressure to disengage the clutch. Also check the brake fluid level. If everything seems ok, bleed the system out and see if that solves the problem. Let me know what you find!
By the way, what year is your 928??? I am trying to get my electric trunk release to work (it doesn't turn on when the button is pulled unless the trunk is already open....). I believe it is wired into the courtesy lights. Do all 5 of your courtesy lights turn on when you open a door? Or just the door lights? The lights on the ceiling/rear hatch only light up when the trunk is open, which I think is part of the problem.
Mine is an '86 Euro (16v). I had a shortage in the very rear courtesy light, which fried the wires completely, and I had to cut the wires of to prevent further damage. Although the front ceiling does light up with the door ones. Your problem sound to me like a broken wire, that is pressed in a certain way when the hatch is closed, so that it doesn't function. I really don't have much nowledge about it, since I'm new to the car, and hasn't had problems with my hatch release..
Nice, Euro models are awesome! Does it have the higher HP motor? I guess I need to check the wiring for breaks/shorts somewhere. I think that if I can find out why the ceiling light doesn't come on when the doors are open, I can fix the trunk release too. I checked for voltage at the wires leading to the trunk release switch, and found that there is 12v to ground on BOTH wires!!! However, when the trunk is open, one wire loses the 12v to ground, and the trunk release works. The wiring diagrams are nearly impossible to follow, so it is hard to tell how the circuit is actually supposed to work. Good luck with your clutch!
Yeah, she's pretty wild! 310 hp, and 0-60 in 5.7 secs (measured) :b It's actually faster than an S4! :o And I, unlike many, prefer the OB-cars. Thanks, and good luck with your wiring, it can be a pain in the a**. I just spent several hours sorting out a PO's hack-job with the stereo, so now all 8 of my speakers are playing, and playing gooood. The original Blaupunkts are not too shappy! Although my car has some factory "klang-paket" (sound-package) upgrade, so maybe it has something to do with it ;) Will reply with results clutch-wise, but it's probably what you said. Hopefully bad hose/pipe, I'm crossing my fingers (and toes, and arms, and legs and, and, and..)
Any luck with the clutch??? I finally got to reinstall mine after it began making some terrible shreeking sounds for no apparent reason, and now I have the same problem as you. Pedal has waaay too much free travel, and after spending an hour and a whole bottle of brake fluid bleeding it, it is still not disengaging properly. I can get it to work by adjusting the pushrod on the pedal and driving it for a bit, but after letting it sit for a few hours the problem comes back!!!!! Air bubble in the clutch master cylinder??? There are no apparent fluid leaks anywhere.....I may have introduced some air when the slave cylinder was removed. I will try the factory technique next; pushing the slave cylinder pushrod back into the bore to push air back up to reservoir. Hope it works, I really don't want to remove the master cylinder!
I had an issue with my clutch master cylinder, and from what I hear it is a recurrent problem. You are looking at about $400 in labor to change out a $45 part, the reason being the entire fender must be removed and a hole must be made in the firewall to remove it because Porsche decided to make it a part of the firewall lol. The best advice I can give you is to replace the brake master cylinder while your in the hole as the labor is not worth doing it twice. Also make sure your mechanic cuts a "cheater" hole in the fender while he has it off so you don't have to remove it for the next time.
I bought a Street/Sport clutch from SPEC for $900. I have been extremely happy with it's performance over the last year, even taking it on a 1,500 mile rally through the mountains, without a single problem.
The clutch master cylinder on my car is new; it looks like I introduced some air into the system while replacing the clutch. The factory bleeding method of pushing the slave cylinder pushrod back into the bore worked very well, although it took some time.
Kyle and 928_Bentsen: I recently purchased a 84' 928S Euro and I believe yours is also '84 Euro ? Incredibly, I drove it from the seller's garage to my house fine....The next day, I could not get it into Reverse , and it goes straight to 2nd gear. I am a Porsche fanatic, BUT have 0 mechanic skills. Basically, I can drive it in 2 , 3 and 4th gear, and took it no further for fear of blowing the clutch. Any ideas?
Sorry for your troubles. Do have this car repaired properly for max enjoyment. While at the shop have the car's brakes checked as well. I also recommend advanced driving schools courses. What we do not know about cars gets us killed or injured. I have attended 3 and plan on another one in 2012. Enjoy the car. Best of luck .
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