bureau13

Same symptom as before but no kickdown relay to blame this time. Driving along, engine just stopped, all lights on. Tried to start again, it actually briefly coughed but then nothing. It just cranks now, like before. I have some relays on the way but they're not here yet, unfortunately.

I did notice that when I crank it, the tach moved very little if at all. The thing is, I'm not sure how much it should move normally. I never really noticed that before.

Not a big fan of the getting stranded thing :-|

Mrmerlin

might be a relay, also check the fuel pump fuse see if the surrounding area looks burned if so then the fuse holder fingers are loose
use Deoxit

Landseer

I'd like to see you replace the crank position sensor sooner in this process rather than later.

bureau13

For what it's worth, I went back to the car a few hours later, and it started right up. I got me to the on-ramp of the highway (naturally) before it decided it was done and once again, died. I had it towed home, where she's currently sitting in the driveway pouting. B*tch

Do relays ever fail intermittently like this? My expectation for a failed relay would be that it stops working, not that it sometimes works, sometimes doesn't. Then again, I suppose it could work this way...have any of you seen them fail only some of the time?

Whatever it is, it's clearly some sort of electrical connection that is bad. Just need to figure out where. Meanwhile, even if it starts up again tomorrow I guess I won't dare to drive it.

bureau13

The CPS was replaced by the PO (I bought it, had it sent to him) about 2-3 months ago. It was trashed, but I wouldn't expect a new one to fail so quickly. I would hope!

uncre8tv

When's the last time you cleaned the grounds? Particularly those bastard ones under the air cleaner/fuel dampers... Intermittent issues like this were solved on mine by going through the whole ground chart and hitting every one with an emory sponge.

bureau13

In all honesty Ive never done that

potdog

Hi same problem with mine last year spent loads of time cleaning earths replaced every thing but E.Z.K. It would be fine some days and then only run for a short time changed E.Z.K. no problems since cheers.

Gerald Finden

http://www.jdsporsche.com/fault%20find.html may be helpful. Good luck.

SteveG

In the manuals and I think in the new visitor thread is a diagram of ground points. You really need to do it. Yours sounds like one of the coil grounds.

A new batt gr. strap too if it is original, it's possible for there to be deterioration under the rubber coating.

Bertrand Daoust

Ground points location.
Post #33.
https://rennlist.com/forums/928-foru...estions-3.html

bureau13

Funny you mention the coil grounds. As I mentioned in another thread, my driver's side coil ground wire is not attached to anything on the side opposite the coil bracket. It's never been attached, as long as I have owned the car, and in fact I initially couldn't find the point where it's supposed to attach (back of cam gear cover, way down where I can't reach it of course). I haven't been thinking that is a likely candidate here, because it's always been detached, but maybe that's not correct thinking.

Bertrand Daoust

I don't think it would give you that kind of problem.

I found one (coil ground) disconnected on my car when I bought the car and it did not quit like this.

Like Stan said, it could be a relay going bad.
It can be something else but I would start with the simple things first.
Like this and the ground points.

I'm going to the garage this afternoon. I'll get a pic showing where the driver's side coil wire goes.

soontobered84

After you check the relays (RELAYS, RELAYS, RELAYS) and fuses per Stan's recommendations, clean the grounds at the back of the engine on either side of the V. They are hard to see and hard to get to, but the engine computers rely on those grounds to work properly. Also, get that ground connected to the coil just for good measure. Bad grounds in any car can cause all kinds of havoc.

bureau13

I think I know now where that coil ground goes...after wrestling to get it attached (and failing...I don't seem to have the right sized bolt, so I'll be making a trip to the hardware store later) I said let's just try something else for fun, and jumpered the fuel pump relay (keep in mind I had done this before, but it didn't fix anything). Sure enough, it started right up. I put the relay back...and it also started right up. Do relays fail like this, where they start to go bad? I guess there's no reason they wouldn't, I just don't know if it's typical. Of course, it really could be any of the relays, or the grounds or computer etc etc etc at this point. I really am not much closer to the real root cause than when I started. (*sigh*)