924Board.org

Porschejag · Joined: 06 Nov 2008 Posts: 31

So, I go on about a sixty-mile trip with my buddy. He's really diggin the 924s and inquires about many of the common consumer questions (reliability, gas mileage.. that sort of stuff) Anyway, I say, "Yeah, I'd definitely trust this car on a cross country trip.. no questions asked!!"
About twenty minutes on down the road, pulling basically on the last stretch of road before my house... I turn right. -Not a hard right turn by any means, mind you. Anyway, the car just dies. No sputter. No warning. Nothing. Ran normal the whole trip. Obviously, I have gas.. So that wasn't the problem. Battery is charged. Anyway, I didn't want to get too involved on the side of the road, so a couple of good ole' boys drag me home.
I'm still in the process of troubleshooting, but have come across a few questions.
-Does the Ignition coil get hot on both sides? I know on some previous cars that I've had that they don't. This one seems to, though. I even took on off of the parts 928 and tried it, but still the same response. Maybe both are faulty.
-And any other troubleshooting ideas would be greatly appreciated. I've quickly read over the Haynes book, but haven't really gotten involved too terribly much yet.
Thanks in advance!! (Assuming I get responses, lol)

Fifty50Plus · Posted: Fri Jun 11, 2010 12:50 am Post subject:

You parked it too close to the Jag once too often.

Check for spark. Check for fuel.
_________________
1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

headstrong2740 · Joined: 29 Apr 2010 Posts: 111 Location: Moline IL

check your fuel filter and pump,

Could it possible be the IAC valve?

Porschejag · Joined: 06 Nov 2008 Posts: 31

Whoa now! Don't be knocking the jag (The xj-s was my boyhood dream!! Well... along with the Porsche(s).. and a few other untouchables, of course), lol! Although, at this state of my life, if I had to pick one of the two... it would definitely be the Porsche.
Anyway, the first thing I checked was the fuel filter, but it didn't seem to be clogged or anything. The next was to see if it was getting spark. It is not. That led to checking the ignition coil, but it seemed to be in working order. Then I ran out of time.. and had to go to a cookout. Tomorrow, I'll check all of the other ignition stuff. I don't think that's the problem, though.. because I changed all of that stuff (Cap, rotor, plugs, wires.. etc.) when I first got the car. Keep the flow of ideas coming, because I appreciate it very much!
It picked a decent time to get under the weather, anyway. I need to do a few things to it. I suspect the head gasket is worn and leaking a bit of oil.. so I plan to replace that. Perhaps other gaskets while It's stalled for a while. Then I'll go ahead and change the oil.
-Priorities first, though! Got to get her running again, -immediately!

headstrong2740 · Joined: 29 Apr 2010 Posts: 111 Location: Moline IL

If you're not getting spark you might want to start tooking at any sensors that are associated with the spark. I dont know if our cars started using cam and crank sensors yet to control that, but if they do (still learning) i would start looking there.

IF NOT then you need to start looking at your coil and possibly pull it and test it, check your wire from the coil to the cap, pull your rotor and cap and check them. Even though you replaced them recently, you might have an issue in there you're not aware of.

Hope you figure it out soon.

Paul · Posted: Wed Jun 16, 2010 9:10 am Post subject:

Pop in your spare DME relay, should be one in every 924S glovebox.
_________________
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.

Porschejag · Joined: 06 Nov 2008 Posts: 31

Firstly: Thanks for the responses, everybody! I've still had no luck getting this sucker started. It just turns and turns, but still not getting any spark. Anyway, I did check the Ignition coil, cap, and rotor and everything seemed spot on. -I do agree with the DME relay suggestion! I actually didn't think to check that because the fuel pump was running fine and I completely forgot that it had two contacts. ..BUT.. I did pull it and checked the connections. They looked fine. Nonetheless, I created the ole emergency jumper to completely check it. Still have the same problem. I suppose that there is a bit more heavy reading that I need to be getting into because I'm having some major 924 withdrawals!! I'm going to look into the cam and crank sensors. I too am relatively new to this domain. -All other suggestions or ideas would be appreciated as well!!!

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

A systematic and methodical approach is highly recommended. Start here:
http://www.clarks-garage.com/shop-manual/ts-01.htm

Then here:
http://www.clarks-garage.com/shop-manual/ign-04.htm

Good luck!
_________________
erstwhile owner of just about every 924 variant ever made

Porschejag · Joined: 06 Nov 2008 Posts: 31

So, I've checked everything. All the basic ignition set-up stuff. All of the Sensors. All connections, relays and the likes. Everything was in order.. But still no spark! The only thing left, that I can reckon, is the brains of the car. Obviously (and sadly), I don't have a spare one laying around to check that idea. Soon, I'm going to take it out and check the solder joints. -That Clarke and his garage sure is a helpful little site, eh!? Any other ideas on this little no spark problem surely would be helpful!

John_AZ · Posted: Wed Jul 07, 2010 11:28 pm Post subject:

When you grind the starter, can you see the tach guage needle jump a little----1/16th of an inch?

If no jump, it could be the reference sensors.
Check the resistance of the sensors per Clarks. IGN-2

Check to make sure the rotor is not loose.

Check the negative ground wire and clean the contacts. Put a piece of tape over the TDC hole to avoid dropping a nut in the clutch.

Crawl under the dash and wiggle the DME computer big connection.

GL
John

Porschejag · Joined: 06 Nov 2008 Posts: 31

Thank ya, John! I've done all of that... still nothing new. I'm sure that the problem is the dme computer. I'm trying to find a cheap(Somewhat) used one, but still no luck.

bcblase · Joined: 23 Oct 2007 Posts: 574 Location: Winchester, VA

I have a spare DME, but not wanting to part with it unless offered a ridiculous amount of cash. You might want to try a local junkyard, or one of the Porsche recycling facilities.

There are a couple of places that can fix your DME for a flat fee - I have seen the website or phone numbers posted on this board before. You might try searching.

Brad
_________________
1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver

Porschejag · Joined: 06 Nov 2008 Posts: 31

Finally got a used brain box. Swapped them out and it started up perfectly! I'm glad to finally have it breathing again!

mehall · Joined: 15 Dec 2008 Posts: 191 Location: Richmond, MO

Were these DMEs manufactured by Ford or its subsidiaries? 80s Fords often failed as catsrophicly.

Porschejag's description of the incident matches many stories I heard from Ford hampered friends.

Obviously ours were better constructed; they lasted longer! But they share the same logic that causes failure with no warning symptoms.
_________________
Mark

'87 White 924s manual
'94 Lexus LS400

www.kcws.org