924Board.org

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

I'm at a loss here guys.. I think either my speed or reference sensors are bad, but I don't know which one it could be. This is the only thing I can think of that is making the car randomly die.

Yes, I have replaced the DME relay 2 years ago with a brand new one. Yes, I made the jumper wire for backup. Same results...

Fuel pump was replaced in 2007. Fuel filter in 2007, then again in 2010.

It seems to happen between 10-30mph. I haven't experienced it yet on the freeway, but it seems to be getting worse and worse, happening more frequently, which is why my initial thought was the DME relay.

Temperature has no effect; cold engine, warm engine, hot weather, cold weather.

The way it dies, is as if the fuel pump just gives out. A total loss of power and then the car tries to run on no fuel. Sometimes it will start right back up no problem, but I usually end up with a dead car coasting in neutral to a stop with the alternator light and oil light on.
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Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

lots of possibilities. Check your fuel pump FUSE (not relay) for corrosion on the tips. Speed and refrence sensor function can be checked at the DME plug. I will try to find a link...
_________________
87 924s
88 924SE gone
447 hp cgt clone
87 924S gone
84 944 sold
83 944 sold
89 turbo S LSD, ABS etc
86 951 white rocket
85 944 sport everything.
84 944 sold.
87 944 sold

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Here is a link describing speed and refrence sensor check.

http://www.924board.org/viewtopic.php?t=36094&start=0

Make sure to click the link within the above link that shows the DME pinout.
_________________
87 924s
88 924SE gone
447 hp cgt clone
87 924S gone
84 944 sold
83 944 sold
89 turbo S LSD, ABS etc
86 951 white rocket
85 944 sport everything.
84 944 sold.
87 944 sold

joejax · Posted: Fri Jul 20, 2012 6:03 am Post subject:

"Car randomly dies while driving..."

I thought that was normal for a 924.

Sorry...
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I got nothin'
Uhhh...you got any pics?

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

I saw this thread a while back of someone checking their fuel pump fuse in which it LOOKED okay.. until they pulled it out.

This one has to go in the record books..

Check it out! This is my fuel pump fuse.

_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

Well, as it turns out anyways, the car died on me again on my way home. I was sitting at a light. Back to square one..
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

So what I noticed is if the car doesn't start or it dies, smacking the crap out of the dme computer gets it to start up and run again. I've tried tapping the relay in hopes the vibrations from when hitting the computer was actually making it start, but it didn't make a difference. So if I take apart the computer what should I look for? Bad joints? Any common areas where these go bad?
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

edredas · Joined: 09 Dec 2004 Posts: 861 Location: Charlotte, NC

Sorry, I don't have a better picture, but check the solder joints where this connects to the board.
_________________
'84 944 -White, Brown interior
'84 944 -Red, Automatic
'86 944 -Garnet, Fully loaded, Koni suspension
'87 924S -Red, 300hp 951 swap
'87 924S -Red, Project Car
'88 924S -Red, Daily Driver

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

Okay, will do. Would that be a possible cause to random dieing?
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

edredas · Joined: 09 Dec 2004 Posts: 861 Location: Charlotte, NC

Yep, it would cause just what you've described.

You can't always see the cracks, so be sure to reflow these joints no matter how they look.
_________________
'84 944 -White, Brown interior
'84 944 -Red, Automatic
'86 944 -Garnet, Fully loaded, Koni suspension
'87 924S -Red, 300hp 951 swap
'87 924S -Red, Project Car
'88 924S -Red, Daily Driver

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

Okay, thanks man, you come to the rescue AGAIN for me! you rock. Can't wait to tear that thing apart. If I find anything funny, I'll post a pic.
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

Okay, I got the DME apart, found the solder joints you mentioned and low and behold.. 2 of those 3 joints are cracked in a circle. I tried getting a picture but they all came out bad. I have one decent picture if anyone wants to see it, but it's definitely cracked.
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)

edredas · Joined: 09 Dec 2004 Posts: 861 Location: Charlotte, NC

How did it turn out, did it fix your problem?
_________________
'84 944 -White, Brown interior
'84 944 -Red, Automatic
'86 944 -Garnet, Fully loaded, Koni suspension
'87 924S -Red, 300hp 951 swap
'87 924S -Red, Project Car
'88 924S -Red, Daily Driver

Coolbri1191 · Joined: 07 Feb 2010 Posts: 78 Location: Simi Valley, CA

So far so good! Did a test run, hit the computer a few times to see if it would die, and everything is great so far. I re-soldered pretty much the whole board, including the 3 bad ones. Thanks for all your guys' help!
_________________
Guards Red 1987 Porsche 924S (Automatic)
2001 Ford Explorer Sport (DD)