Notices
911 Forum 1964-1989
Sponsored by:
Sponsored by: Intercity Lines, LLC

Vapor Lock?? Car dies...hmmm

Thread Tools
 
Search this Thread
 
Old 06-18-2006, 10:33 PM
  #1  
markweintraub
Intermediate
Thread Starter
 
markweintraub's Avatar
 
Join Date: Nov 2003
Location: Westchester County, NY
Posts: 36
Likes: 0
Received 0 Likes on 0 Posts
Default Vapor Lock?? Car dies...hmmm

I'm running a stock 87 911. Car runs great. 55k miles. Not sure if you can get vapor lock in a fuel injected car -- but i'm at a bit of a loss.

Took it out for a father's day romp. After it was warm - I drove it pretty hard. Then, I let brother drive for a few miles. You know that feeling when someone else is driving your car -- just not exactly the right way -- but nothing major. He was driving it very gingerly.

At a stop sign, we make a turn and go up a steep hill. He shifts into second when the hill needs first. He shifts in first and the car dies. We let it roll back to the bottom of the hill -- and try to jump start it by pushing. No dice.

I just went back after letting the car sit for 45 mins and it started right up. I went back up the same hill -- at speed -- and the car died.

BTW -- not sure it matters -- but it's 80 degrees here right now.

Other than this, the car runs great. Just had the oil changed a few hundred miles ago.

Any ideas? I'm going to let it sit a few more hours and go back and try again.

Thanks.
Mark
Old 06-19-2006, 12:03 AM
  #2  
markweintraub
Intermediate
Thread Starter
 
markweintraub's Avatar
 
Join Date: Nov 2003
Location: Westchester County, NY
Posts: 36
Likes: 0
Received 0 Likes on 0 Posts
Default Update -- Car is fine...

I let it sit for 90 mins and it's back to normal. My only guess is that it was a bad combo of my spirited driving followed immediately by my brother's conservative driving -- almost short shifting the car.

I'll have it looked at -- but would appreciate any thoughts y'all might have.

mark
Old 06-19-2006, 01:44 AM
  #3  
Steve Weiner-Rennsport Systems
RL Technical Advisor
 
Steve Weiner-Rennsport Systems's Avatar
 
Join Date: May 2001
Location: Portland Oregon
Posts: 11,871
Likes: 0
Received 64 Likes on 48 Posts
Default

Hi Mark:

Fuel injected cars car exhibit vapor lock in hot weather but that usually occurs when the fuel level is at, or below 1/4 tank. One prevents this by keeping the tank 1/2 full or better when its hot outside.

Since you didn't say how much gas was in the tank, its hard to say whether you experienced that or not.

I will mention that the DME relay is troublesome on these cars and an intermittent one will cause the same symptoms. One ALWAYS carries a spare in any Motronic-equipped Porsche just for these contingencies,...

If you don't know how old yours is, I'd strongly suggest that you replace that (and get a spare for the glovebox) as a good measure to keep you from walking or calling a tow truck. This relay powers the fuel pump as well as the DME and when it fails, you are done. You'll find it under the driver's seat.

Last edited by Steve Weiner-Rennsport Systems; 06-19-2006 at 12:45 PM.
Old 06-19-2006, 10:34 AM
  #4  
markweintraub
Intermediate
Thread Starter
 
markweintraub's Avatar
 
Join Date: Nov 2003
Location: Westchester County, NY
Posts: 36
Likes: 0
Received 0 Likes on 0 Posts
Default DME

Steve -- thx for your swift reply.

Car is 3/4 full of fuel.

I've owned the car for 2.5 years. My guess is that the DME is orignial to the car. I'll go ahead and order two DME relays. I've heard that a spare one is a good insurance policy.

Is replacing the DME relay as easy as it looks?

Mark
Old 06-19-2006, 12:12 PM
  #5  
madmmac
Instructor
 
madmmac's Avatar
 
Join Date: Nov 2005
Location: Washington State
Posts: 200
Likes: 0
Received 0 Likes on 0 Posts
Default

Yes, slide the drivers seat back as far as it goes, loosen 1 screw, unplug, plugin, tighten screw and away you go.



Quick Reply: Vapor Lock?? Car dies...hmmm



All times are GMT -3. The time now is 04:29 AM.