924Board.org

Rprimm · Joined: 15 Jul 2014 Posts: 15 Location: Virginia

So I bought a 1981 924 (Not the turbo) a couple of months ago and I'm having a little trouble starting it, so I just wanted to see if anyone has any ideas or tips for me. Here's where I'm at now:

I bought it knowing the fuel pumps were bad, so I drained the fuel tank, replaced them both, and put a couple gallons of fresh gas in it. Along with that I have replaced the air filter, fuel filter, and spark plugs. I cleaned the fuel injectors and tested them by hooking them to the fuel lines and spraying them into a cup so I could see if they were spraying. They all sprayed an even amount of gas. I also tested each spark plug wire and they all produce spark.

I have tried starting it with and without starting fluid and I can't seem to get the slightest fire. The one thing I noticed was every time I took the spark plugs out they were filthy, so I looked down in the fuel injector slots with a flashlight and in the front two I saw black sludge on the metal at the bottom (I don't know what to call it, cylinder head maybe?) I sprayed carb cleaner onto it and the turned the engine over with no plugs a couple times to blow the junk out. I put the spark plugs back in and they stay clean for the most part now but I still see the black residue where the carb spray can't touch. I haven't tried starting the car after blowing that junk out because I'm waiting on a new fuel pump relay to come in the mail. I broke the other one. While I'm waiting I would like to try to clean it out as good as I can and I'm wondering how to do that. Can I let a Seafoam-type of product sit in there for a couple of days? I would greatly appreciate any advice. Thanks!

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Combustion of good quality fuel will take care of a good deal of your black gunk. The real question is why is the car not starting?

#1 cause of running problems on these cars is air leaks, followed by control pressure problems. Take a look at the link provided in the "NOOBS READ" thread to familiarize yourself with the functioning of the fuel system.

P.S. NGK Copper plugs, please!
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Rprimm · Joined: 15 Jul 2014 Posts: 15 Location: Virginia

Thanks Rasta, I was wondering if it was air related because the boot that goes onto the throttle body has a small hole in it... I don't know how much it's affecting it but I know it's not helping. I'll check out the Noobs Read

!tom · Posted: Tue Jul 15, 2014 11:07 pm Post subject:

This is the section for the 924S, which is basically 944 guts in the 924 body. You may have better luck with your query if it is in the General Discussion forum.
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78 924 NA
5-lug

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

So, someone ignored the vacuum leak caused by the torn air boot, and enriched the mixture to make it idle. . .hence the black gunk.

Replace that boot. . .they are cheap.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Rprimm · Joined: 15 Jul 2014 Posts: 15 Location: Virginia

Thanks Tom I figured I was in the wrong spot.

Hey Rasta what do you think about these plugs? I just ordered some two days ago. http://www.ebay.com/itm/120911198451?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#viTabs_0

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Recommend NGK BRP6ES. If you must have Bosch, correct plug is Super Plus WR7DC+.

Linked plugs are wrong temp.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Rprimm · Joined: 15 Jul 2014 Posts: 15 Location: Virginia

Not trying to say you're wrong, because you obviously know a lot more than I do, but I'm curious, why do you recommend NGK when (I think) the Bosch plugs are the ones meant for the car... Also the NGK website says use BPR7ES's OR BPR7EIX's for a 1981 924 non turbo, so now I'm confused even more

Paul · Posted: Thu Jul 17, 2014 11:29 am Post subject:

Nothing wrong with Champions, some hood stickers used to recommend them.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.