Hello from Porsche newbie (long)

p-talk · p-talk's Garage

So I just bought an '87 924S, black with black/grey interior. Coming from years of messing with VWs and Audis, it seemed like a good balance of inexpensive 'Porsche-ness' with all the good 944 stuff underneath. I drove it around a few hours the night I bought it, and it was fun though I could tell it needed a tune-up and some suspension bushings, but otherwise was a ball to drive. It has 131k, no rust, is very clean inside and out, and runs OK.

Well, RAN ok

. . .

First, it didn't pass emissions. CO was too high at idle. So I started poked around at vacuum lines, found one that was loose, and one of the fuel inlets to a pressure regulator was just a bit loose too. Started checking tune-up stuff, air filter was good, cap and rotor are worn but not toast, plugs worn but not terrible, etc. Poking around on the forums here I thought it might need either an O2 sensor or engine temp sensor to fix the CO issue.

So I take it out for a spin after fixing the vacuum line and installing new plugs, cap and rotor hoping maybe I'll notice some change (OK, just 'cause I wanted to drive it). I get about a mile away and it suddenly dies. I coast into a parking lot and try to start her up. It runs, but REAL rough, and dies when you give it ANY gas. I towed it home and poked around again, there was one other vacuum line that had popped off, but putting it back didn't help at all. At that point I just called it a night.

The next night I tried reseating the two connectors to the reference and speed sensors, no difference there. My buddy mentions maybe it's out of gas, that the gauge may be bad. We put 2 gallons in and she starts rough, then smooths out after 60 seconds. OK, cool, I can live with the a bad fuel gauge . .

So I take it to the gas station and fill her up, she only took 8 gallons. WOW. OK, so it COULDN'T have been out of gas, these things take like 17gallons or so.

Any advise or ideas? Clogged cat? Maybe reseating the sensors did the trick? Is there some sort of diagnostic connector that will blink out error codes or something?

Thanks, sorry my first post is so long

BTW, this forum is great! I've been doing lots of searches trying to learn the cars and their 'personality'

- have found tons of good info on these cars.

CJFusco · CJFusco's Garage

When the car is running rough, try unplugging the O2 sensor. If it improves, you know you have a bad O2 sensor.

Fuel problems can be really tricky to track down. Could be a lot of things, really - fuel pump, bad injector, malfunctioning FPR, or even a problem with the DME itself, or a tank of bad gas.

Don't worry, there are experienced mechanics on this board, and we will help you through figuring out your problem. The best way to do this is to eliminate the cheap/easy possibilities and move on from there.

CJFusco · CJFusco's Garage

Oh, here's another "cheap/easy": check to make sure that all your plug wires are secure on both ends, and that your spark plugs are screwed down securely.

Razorback1980 · Razorback1980's Garage

The first thing to try is to make sure you have sufficient fuel pressure. If you have a gauge and can put it on the end of the fuel rail, that would be great...if not, then wait until the engine is real cold and then turn it over long enough to build fuel pressure and crack the fuel lines just past the fuel filter. If you have quite a bit of pressure, then move on. It could be a dirty fuel filter, clogged filter in the fuel tank (not sure what the actual name of that is but there are several posts on how to clean it...do the search and if you can't find anything..then ask). I think that would be the place I would start first anyway. Seems you have done pretty well with the ignition...so far at least. One other thing to do with the ignition is open the hood at night while it's running rough and look for any sparks. Of course you could run your hands close to the plug wires during the day, you may shocked what you find!

p-talk · p-talk's Garage

Thanks for the replies! I drove her lots today and had no problems. I'll check the plug wires for the 'night show' soon, and hopefully if it was bad gas that'll be worked out with the fresh tank. Got a new fuel filter and can hopefully install that soon, though holidays will be taking more of my time (the 924S was my gift

).

SolReaver · 12-17-2006, 09:44 PM

Hey, welcome, condolences and congratulations.

Cam and balance belts ASAP, really.
Go over the car and check and clean connections.

nynor · 12-18-2006, 04:07 PM

have fun with the filter. my experience is that they have never been changed and are really on there!!! spray it with some PB blaster (or whatever) a couple of days before trying to remove it.

that said, i would put a bottle of techron in there just to make sure. can't hurt.

p-talk · p-talk's Garage

Already running the Techron, I love that stuff! Got the filter but won't have time to change it until after xmas - leaving town. I'll miss the Porsche

. .

Quote:

Originally posted by nynor
have fun with the filter. my experience is that they have never been changed and are really on there!!! spray it with some PB blaster (or whatever) a couple of days before trying to remove it.

that said, i would put a bottle of techron in there just to make sure. can't hurt.