930 shuts off while I'm driving

erikg · 07-25-2001, 03:42 PM

Ever since my last DE, my ruf 85 930 will just quit while I'm driving. At the DE it was poring rain, and it seems always worse after rain. It seems to be electric, since there's no warning at all, no stuttering, no nothing. I can be doing 80 mls an hour and suddenly the car quits. If I just push in the clutch and release it the car will not restart, but most of the times I can engage the clutch, turn the key to off and then start the car while it is still rolling. The tach seems to be connected to the problem since it'll work fine when I just start the car, but after 10 minutes of driving, the tach quits, and soon the car will start shutting off. I have replaced the ground strap to the battery but to no avail. I have cleaned all the wires that I can see in the engine department and will replace my distributor cap and rotor tomorrow. Anyone any ideas ???. It usually happens after I accelerate and then attempt to shift to the next gear. Heeeellllppp !!

John Rogers · 07-25-2001, 08:42 PM

You might want to check the relays in the engine compartment (if your RUF has them on the left side under a cover like our 1987 Turbo)? I had a yellow one keep working loose and when it lost contact the car would stop. Also check the connector on the ignition box to make sure the plug is in tight and there is no corosion. Good luck.

Jens Wendorff · 07-26-2001, 05:42 AM

Check also the 14 pin connector/s (don't know the 930 setup, but believe is similar to 911) and esp. the electrical connection at the fuel pumps. Stalling can appear when the car is not getting enough fuel!

Guess how I know

Jens

cstreit · cstreit's Garage

THe connector on my 82 Turbo for the HID unit (used to fall out all the time, or stop when it rained. A dab of silicone on it stopped that from happening...

Did the same thing with the fuel pump relay as that would quit too....

erikg · 07-26-2001, 06:30 PM

thanks guys, i'll keep you posted after installing the next rotor and distributor cap and silicone the hell out of all the connections in the engine dept

erikg · 07-28-2001, 01:57 PM

I'm having no luck, I cleaned every connector I could find in the engine compartment and put some electrical silicon in the plug before I plugged them back in. Replaced the rotor and distributor cap, but the first test drive was even worse then normal. Every time I let off the gas (usually when I shift) if the car was above 3000 rpm, it shuts off. Can a relay be bad to the point where it works fine to a certain point, and then quits, or do they either work or not ?. There's a round relay in the right side of the drivers side that cuts off the engine immediately after I pull it. Where is the pickup for the tach ? The problem still seems to be related to the tach, and the car will start it's problems minutes after the tach bounces all over the place and then quits and shows 0 rpm.

dheinz · 07-29-2001, 07:04 AM

erikg
I had a simalar problem with my 82 Euro SC. Unexpected shutdown, would not restart by popping clutch, but would restart instantly with key.I checked all the usual suspects,relays,fuses, wires, etc.My solution was found in the O2 sensor wire in the left side of the motor compartment behind the cover.The wrench said it was sending signals to the CIS to shut down the fuel delivery.The O2 wire had worked loose and was intermittently touching the catalytic converter The wire was secured in its proper place and a very annoying problem was solved.I hope this helps.
Eddie

CRJ-Jockey · 07-29-2001, 08:44 AM

Erikg, the relay that shuts off the engine is the fuel pump relay. As about you jumping tach, thank God that someone else had the same problem...Mine does the same thing, and yesterday the battery light came on and the car died instantly. It has happened three times so far. If you ever find out what the problem is please let me know.Mean time I am looking for answers myself...

erikg · 07-29-2001, 05:08 PM

Eddie, I have GHL headers and mufler, so I don't think that I have an O2 sensor anymore. Any other ideas ?? Does a fuel relay shut the car off that instantanously ?. The car litararelly shuts off as soon as I pull the relay. If the car shuts off that quickly the fuel shuts off, maybe the problem is not ignition related, but fuel related. Although that would still not explain the tach....???

erikg · 08-02-2001, 03:17 AM

I'm bringing the car in to the shop, can't find the short. After talking to Prototech, they advised that I had a short somewhere, which would shut down the brain, which explains why the car starts right up if I turn the key to off and start the car again. He advised not to drive it, since the short could eventually fry the "brain" which is expensive to replace. I'll let you guys know what was the result in a couple of weeks; I'll be on vacation in Aruba....

Marshall Deems · 08-31-2001, 01:46 PM

Have you returned from Aruba? I have been following your problem and am anxios to here what the shop found.

88911coupe · 08-31-2001, 02:41 PM

My friend with an 88 930 was running into this exact problem and it turned out to be related to the security system the PO installed. It took a long time for the mechanic to figure this out. Just something you might look into if you have a security system.
Good Luck,
Buck

Bob Albo · 08-31-2001, 05:03 PM

I had the same problem and it was my distibutor I tryed everything then found out by replacing it and it wasn't cheap.

BOB

jbripps · jbripps's Garage

I concur on the distributor advice. Same thing happened to me with my Ford Probe - GT (mazda engine) many years ago. I let it go until the car wouldn't start again. The distributor was replaced, and it ran like a gem.

JON
'85 targa

Marshall Deems · 09-06-2001, 09:55 PM

Where's ERIK? Aruba must have really nice hotels or really nice jails! My '87 Turbo has the exact problem and no solution. A few have suggested that I change the green wire from the distributor which I did. Unfortunately you only get a six inch wire from the dealer that plugs into the distributor. One has to purchase the air sensor connector to make the splice. The problem still exists. Don't know if the problem could be the portion not replaced. Don't know where it ultimately ends up since it disappears into a loom. I think it goes to the control box. Doesn't it make sense that if the distributor was bad, there would be some evidence of pending failure on a regular basis. My car runs perfect 99% of the time. Perhaps I could borrow a distributor from someone?? I hooked up a timing light to see if I was getting a spark, but the car starts right up after if stalls. This is really gettin' me down.

Bob Albo · 09-07-2001, 05:05 AM

when I had this problem it was a few years ago, my wrench could not figure it out until
I developed a noise in my distributer, like a barring has spun. It was replaced along with the green wire and all has been well ever since, so that's why I beleave it may be the distributer.
BOB ALBO

nhromyak · nhromyak's Garage

Don't the 930s have TWO fuel pumps?

Therefore, aren't there TWO fuel pump relays?

Just some thoughts.

------------------
Nick Hromyak
'85 Carrera 7 & 9 Fuchs
Havin' Fun in Sacramento

rboylan · 09-07-2001, 12:35 PM

I'll bet dollars to donuts the problem is in the distributor. I have a European 930 and the rotor in the distributor has a spring mechanism that causes shutdown under hard driving conditions(by design for some reason I'm not sure of). If the problem occurs during hard acceleration, check the rotor. Good luck.

Rich Boylan

twin plugged targa · twin plugged targa's Garage

Mine is an 86 Carrera which had similar symptoms which I now suspect may have been caused by a hard run at an auto x.
The culprit was the distributor which would only drop 1/4" after the car had warmed up.
It 1st happened in the pouring rain- which sent us on the complete wrong track of bad wireing and shorting.Car would Idle fine but on acceleration- die
Finally after I changed the rotor and cap the car ran for twice as long as normal but ...... died!.
I never looked at the cap and rotor- dissmissing it -BAD, REAL BAD!!!!!
This cost me $1000 as I had it towed to a mechanic who charged me for troubleshooting only to tell me the problem was that the exhaust valves/guides were worn "SAY WHAT!"
The end float for the dist. was 1/4" out maybe by the cogs pulling the drive gears downward?.
Anyhow a $100 distributor fixed it!

It is definately worth checking the distributor and it is easy to do!.
Hope you learn by my mistake!
rgds Ben

[This message has been edited by 86ragtop (edited 09-07-2001).]

john walker's workshop · 09-07-2001, 04:18 PM

the wild tach would give a hint that the CD ignition unit may be bizerk. the tach runs off the unit. they're famous for failing. a bosch unit is scary expensive. a permatune is affordable. does the same thing in a different way. also check the green coax cable that plugs into the distributor. heat causes the cable to disintegrate right where it plugs into the distributor. if the inner wire touches the outer braided ground,
instant death. generally that won't kill the CD unit though. you need to check for both spark and fuel pressure when it dies or you will waste more time. with needle nose pliers, pull the high tension coil wire out of the center of the dist cap, hold it a couple of inches back from the tip and have someone work the starter to see if there's spark jumping 1/4" from the wire to ground. fuel pressure check: key on, find the CO adjuster where you put the allen wrench in to adjust CO. (it's right between the air filter housing and the fuel distributor). push down real hard with your finger. it will take up the slop for 1/2" and then begin to move the sensor plate arm as you push harder.if there's fuel pressure, you will hear the injectors whirring (squirting). don't do it too long or you could flood it. spark or fuel. find out.

[This message has been edited by john walker's workshop (edited 09-07-2001).]