Shawn Stanford

(Cross-post from Pelican Forums.)

Good morning.

BLUF: This is my first 911. I'm primarily a 928 guy, with a couple of Boxsters in my past and a Cayenne for a daily. Other than building the 1/4-scale kit my wife gave me for Christmas, I have zero experience with air-cooled Porsche engines. I'll also admit that, while I can follow instructions and swing a wrench, I'm terrible at diagnosing. I often take my cars to my mechanic and have him diagnose problems that I then fix.

The car in question is an '87 Cab with a fiberglass 993 body kit that I bought running and driving for stupid cheap money. After purchase, it sat for a year while I deployed, but I started driving it last spring. It ran well at first, but over the summer it started to miss and backfire when it warmed up. Now it does so immediately on start. After a few moments of this, it quits and won't restart immediately.

At this point, I haven't done anything, since I've been focused on the 928s and my daughter's Boxster. But, other than the absolute basics (air, fuel, spark), I have no idea how to go about troubleshooting this engine, or what the likely culprits might be.

Thanks in advance for any advice.

Here's the car back in May, transporting a 928 door.

wildcat077

Shawn , try swapping out the coil for a known good one ...
It's a long shot , but something simple to rule out.Some older coils will cut out when they get hot , otherwise a DME swap would be the next easy step.

Cheers
Phil

TheTorch

Shawn,
Would help to know if it's a stock 87 ignition/ intake/ fuel, etc. or carbs, or some mix of things.

Methodically narrowing it down is always the best approach if you have the time, tools and skills. This sounds similar and lot of info:

https://rennlist.com/forums/911-foru...g-mystery.html

Shawn Stanford

OK, thanks.

AFAIK, the engine and harness are completely stock. The electrical in the car is a mess, but it's always run well. The electrics was actually going to be my winter project before this reared its head.

I'll also read through that other thread. Thank you.