FCSFrank

As the title says - HELP!!!!!

No start on a 91 auto.

Here is the story……….

Friday afternoon (050908)I washed the car and put the car in the garage after drying.

Saturday at 0730 I started the car to attend a local car show. The car was hard to start and ran extremely rough. I think I experienced “limp mode”. It ran rough for the next 20-30 min until I got to the show. By the time I got to the show it was running slightly better. Parked at the show for about 40 min then decided to go and get breakfast. Had a hard time starting the car but it did start and still ran rough especially while briskly accelerating. At the diner I let the car run while we went in and had breakfast so that it could dry out better. But it still ran rough. After the show the car ran better but still missed at times.

Sunday - Went for a Sunday drive. The car acted normal except the “check engine” light came on and off a couple of times but other then that the car seemed normal. Great acceleration, good idle and start up was fine. Sunday evening - took the 928 to go get pizza for the family. The car was hard starting. Had to floor the peddle to get it to fire. Did this a couple of times. The last time got it to keep running long enough to get some RPM then the rough running cleared up. The trip for pizza was uneventful except for the occasional “check engine” light. When I arrived home I was backing the car into the garage. Stopped in the driveway to wait for the garage door to open and then proceeded for about 2 feet and the car died. No electrical anywhere. Nothing has any power. Checked the battery and it was over 12V. Had to push the car into the garage (not as light as they look).

I’m thinking (hoping) a fuse or a relay or something along those lines??? I have Jim Morehouse manuals on CD along with some other stuff. I have Little to no 928 mechanical experience but mechanically inclined.


No 928 mechanics near or other 928 owners. The closest 928 owner probably would be in Denver, 300 miles away. Any and all help or suggestions would be greatly appreciated.. If I could phone a Guru that would be even better.

Thanks in advance

Frank

85fortheDrive

Two points to check. Remove the plastic shield over the 14-pin connector along the passenger's side of the engine bay. Make sure there's no residual water there. Also check the ignition coil. If you look at the engine lifting point on the front side of the right cam /head just up from the exhaust header you should find a lifting point. On the side of this point is a threaded hole for the coil wire to be attached.

We've heard of strange behaviors after washing. Hope this helps.

Tim

Mrmerlin

First check the passenger floor board see if its wet, if it is then your blower box may be leaking water onto the CE panel,
Disconnect the battery and pull every fuse out and check them for corrosion if you find any that look corroded its best to replace the whole set with new ones, use good fuses if this is the case. Also pull the relays out and check the blade connectors, any that look corroded should be opened and the contacts checked ( you can clean the blade parts with a pink eraser as well as the 14 pin connector)as mentiond previously open the 14 pin connector under the hood,

If you dont have a cover for the hot post then you can get one from a 1988 S4 it should fit ,as always disconnect the battery when working on any electrical system.
Also remove both coil wires from each coil and look at both ends they should be clean and corrosion free, make sure that each coil has a thick black wire going from its hold down screw to some point on the head ( theres one for each coil) get a fuse relay chart here www.928gt.com, keep us posted on what you find

Alan

It is most likely to be the battery (kaput) the ground strap for the battery (replace), the battery terminals (clean), the starter big terminal connections (clean/bolt tight) the alternator big terminal connections (clean/ bolt tight) or the jump post terminals (clean/bolt tight).

It could also be the ignition switch - if you still have marker lights

Alan

Mrmerlin

I missed the last line, no electrical anywhere, follow Alans advice first

FCSFrank

Thanks for the ideas. I haven't had time to check anything yet. may have time this evening.

Alan - Would a bad ground on the battery make the car quit while the car is running? the car just quit while I was backing, like some one shut it off. not sure on the marker lights. no horn though.

Keep you posted

Thanks

Alan

Frank - its unlikely a battery connection would cause the car to shutdown - but is possible, a suddenly failing battery (as in massive internal cell shorting) could cause this though... connection failures at the alternator or jump post could cause instant shutdown & virtually complete power loss.

Any of these would cause the symptoms noted if the car stalled initially for some other reason..

I note you said the battery is still >12v - that means it (itself) was not the cause.

Check what voltage you have between the engine jump post and the chassis?

Alan

worf928

BTDT. It's quite possible. A loose ground strap and/or battery terminal can cause the car to simply stop.

FCSFrank

Thanks for all of the thoughts.
I'm going to try to look at it this weekend..
Any other ideas or thoughts???

Thanks Frank

Mongo

You didn't wash the engine did you?

FCSFrank

Mongo - I rinsed the dust off ???

Can you elaborate??

Thanks Frank

FCSFrank

I checked my car today and there IS power to the jump post in front. no lights. passenger floor dry. May try to access the fuse panel, I may have fractured a rib a couple of weeks ago so the fuse panel may have to wait (painful to get down in there) Could some sort of anti theft device been activated? I only have and use the valet key.

Thanks
Frank

FCSFrank

I think I found the problem…… Looks like the battery may be kaput!
Almost 100% sure.

Kind of weird - never have had a battery fail on me like that..

Thanks for all suggestions