was die Scheiße! - 79 911 SC wont run after car wash :(

[FinallyGotOne]

Hey all you gear heads! Happy Freitag!
So was a nice day here in Highlands Ranch Colorado today, jump in the 911 and decide to get some of the winter grime off before heading to work.
Go in a long touchless car wash and notice half way through my car is not running. It would not restart. I ended up being at the end of the rail, a car coming up on me and no way to start the car, so I engage 1st and use the key to chug start along out of the way. Close call. Got about 20 feet and let it coast another 20. Once I was clear, I let it sit a second and tried to start it. It would not even try, just turned over. Then let it sit for another minute or so and it eventually would start then just immediately die. It back fired twice, kinda small whimpy backfires. (it does have that plunger in the airbox) I let it sit off and on for an hour! towards the end of the hour it would fire up immediately, and drop off and die just as quick. No matter how much I tried, trying to catch it with the gas pedal and hold an idle would not work at all. Another 20 minutes went by, and eventually the battery died. So had it towed home. I am thinking something in the CIS is wet? I'm hoping tomorrow it'll just start and run ok. any ideas though? it's not ever done this before.


Happy Friday!


1979 911 SC

[Oh Haha]

Check your fuel pump relay first. The red one in the front fuse panel. They work loose over time.

If that checks out look at the dizzy cap. It may have gotten wet.

Once the battery is fully charged listen for the CD box "whine".

EDit-Happy Friday!

[theiceman]

wow can't belive you would take such a prized item through a car wash first off ..

anyway the points above sound valid .. sounds like a fuel issue as usually no spark is no spark .. you are at least starting and strugle for a bit.

but if that water blasted down through your rrar grill your ignition could be totally saoked .. from leads all the way to cap and rotor.

i would NEVER take my Porsche through a car wash .. even if you guarentee that recycled water has absolutely no sediment in it ( which you cant ) . the soaps they use to clean your car without touching it are very harsh and im sure would more than strip away your prized wax job.

[grizzfan]

+1 on avoiding car washes.

When I hand wash I put a heavy towel over the rear grill to keep water from seeping in.

Tom

[pete3799]

Spray some WD40 inside the dist. cap.

[FinallyGotOne]

Everybody! thanks so much for the advice. You know I have had this little car for I think 9 years, and I never knew I shouldn't go through a car wash. I usually wash it by hand though. I learn stuff all the time I'll def check the fuse tonight, the dizzy was quite dry, but honestly the rest of the engine bay really was pretty wet! It's all Good, today my brain was in the "off " position most of the morning. Last time it goes through a car wash tho!

[Danimal16]

Check the carpet in the back. It may be wet.

[jorian]

Dizzy can condense water vapor from the wash even if it is sealed. I have had this issue in an SC as well. Take care to avoid the rear grille when washing and better yet cover the dizzy with a rag. Remember to pull it out before you take off though!

The engine is warm when you go through a car wash which can produce condensation. If you can wash the car at home before you start the engine.

[Lyle O]

Not to pile on, but to put some data around how bad car washes are (ESPECIALLY the touch-less ones), note that the ph of the cleaning agents are on the order of 13-14!! The level of alkalinity is like oven cleaner, and will discolor aluminum, paint, even the rubber weather seals. OK, enough said...

[FL911SC]

After you check the easy stuff, then ensure your injector sleeves and seals are all seated correctly and are not leaking. If the sleeves aren't fully inserted into the runners, they can leak and allow water in.

[tcar]

Originally Posted by pete3799

Spray some WD40 inside the dist. cap.

The 'WD' actually stands for "Water Displacement".

It works.

[Joe Bob]

Handwash and "I" leave it running......as to getting it running, an air shot into the cap with likely do the job.

The only carwash that gets my ride is the Honda crap box and that is once every 3 months.....

[al lkosmal]

The fact that it fires up and then dies makes me think it is a fuel issue. I'm thinking that your fuel pump is not working. It starts momentarily on the fuel provided by the cold start injector and then dies due to no additional fuel being provided. It probably would not start at all, right when you got out of the car wash, because the engine was still warm and the cold-start injector would not activate....once the engine cooled down, the cold-start injector fired enough fuel to start it, but not keep it running. Can you hear you fuel pump run?

take off the air-cleaner snorkel and filter, turn on the ignition, and reach in and gently lift up the air-flow paddle. This should activate your fuel pump and you should hear the injectors squeal. if not.......fuel pump is not working.

regards,
Al

[timmy2]

While the air cleaner is off, make sure the pop off valve lid is fully seated after the backfires. They can even pop right out

[Bob Kontak]

Originally Posted by theiceman

but if that water blasted down through your rrar grill your ignition could be totally saoked .. from leads all the way to cap and rotor.

If you have an air hose blow out the 14 pin connector.

Unplug and blow out the CD box connector.

[al lkosmal]

Originally Posted by timmy2

while the air cleaner is off, make sure the pop off valve lid is fully seated after the backfires. They can even pop right out

+1

[FinallyGotOne]

OK so finally got home and had hopes of it firing up. It was quiet so I was able to notice, YUP NO FUEL pump! checked the fuses in the bonnet and all are OK. So is there maybe a plug that could have come loose or busted on the pump? I forget where the fuel pump is on this thing- please advise guys. I specifically did NOT do the undercarriage wash at all.

[Oh Haha]

Fuel pump is located just above the steering rack. Remove the stone cover and you will see it.

Did you check the round relays or the fuses?

You can swap black for red relays to verify they work. The power window or horn ones can be swapped easily.

[FinallyGotOne]

I have spent the last two hours reading my Haynes manual and searching Google for a frikkin diagram of my round relays-no luck/. So which one is fuel pump? Going from front of car towards back. Please assist- this should be in my manual

[86 ssinit]

The relay is the first one closest to the front bumper. It should be red. If you take one of the other black relays out and switch it that should tell if it's a relay problem. It may be a loose wire or a ground problem.