problem - died and won't start

bryanthompson · bryanthompson's Garage

Hey guys,

I was driving along yesterday afternoon, just turned right at a stop and was shifting into second when i lost all power. I got pulled over and let the car sit for a few minutes... tried to start again and got nothing. It gets just to the point where it should fire but doesn't turn over. Anyway, i got the car moved to my girlfriend's house, where it sits now... 60 miles away.

My first thought is DME relay or fuel pump. I remember only hearing a 'whoomph' when it died, and the sound came from the rear end of the car.

Anyway, i'm about to order a DME Relay and maybe a fuel pump. I sortof want to wait and try the relay first (yeah, i know i should have had an extra with me. oops

) I didn't have the presence of mind at the time to listen to see if i could hear the fuel pump. I might have her dad or someone who would know about it go out and try to listen to see if it's running.

Does it sound like i'm on the right track?
It's a little strange... i'm sad that it's broken but excited that i get to fix it. Something's definitely wrong with me :P

latunluvr · 05-01-2004, 06:04 PM

Make a 3 way jumper wire with 3 male spades in it. The kind you get at radio shack or wherever. Pull the DME Relay and put one spade into 87, 87b and then 30 in that order. You should hear the fuel pump start pumping when you put it into 30. You can try to start the car with this jumper wire in place. If it starts, then you can blame the DME relay. If it doesn't start, come back here and post again.

SoCal Driver · SoCal Driver's Garage

Easier than that. Pulling the DME relay and jumping the slots on an early 944 is a real PITA. Just get an aligator clip 12" jumper and go from fuse 2 to fuse 3 (on the 8 fuse holder number 1 is toward the door). You can buy these test jumpers in sets of varius graduated lengths. Or buy the clips and make your own.

This will run the fuel pump.

But I question if this is your problem and wouldn't want you to spend money on what is not broken.

If your car cranks real fast and sounds like a sewing machine you have lost your timing belt.

If the car cranks normally then I would check for voltage at the injectors and at the coil with the key on. Voltage at the coil means the ingition switch is good. Voltage at the injectors means the first set of contacts in the DME relay work.

Next get a spare spark plug and pull the wire off of #1 cylinder. Put the spare spark plug in and lay it on the intake. If you get a spark while cranking then the reference sensor is good.

If you can hear the fuel pump for a half seond or so after you stop cranking the engine then the fuel pump is good and the second set of contacts in the DME relay are good. Note the second set of contacts can only work if the first set work.

bryanthompson · bryanthompson's Garage

I'm sure i haven't broken my timing belt. When i did that it the engine wouldn't turn at all, this gets a lot farther than that. it just about fires.

anyway, i have to drive 60 miles (each way) to try any of these things, so that kindof sucks. I think i'll just print everyone's suggestions and do it all at once.

thanks for all the help

SoCal Driver · SoCal Driver's Garage

Broken timing belts will let the engine turn over faster because all of the exhaust valves get bent and thus stay open. I've not seen a 944 that locked up when the timing belt broke.

I've seen them lock up when the head of a valve (usually exhaust) pops off. This may break the timing belt.

ae1969 · 05-02-2004, 07:16 AM

Quote:

Originally posted by SoCal Driver
..........If the car cranks normally then I would check for voltage at the injectors and at the coil with the key on. Voltage at the coil means the ingition switch is good. Voltage at the injectors means the first set of contacts in the DME relay work.

Next get a spare spark plug and pull the wire off of #1 cylinder. Put the spare spark plug in and lay it on the intake. If you get a spark while cranking then the reference sensor is good.

If you can hear the fuel pump for a half seond or so after you stop cranking the engine then the fuel pump is good and the second set of contacts in the DME relay are good. Note the second set of contacts can only work if the first set work.

That will definitely narrow it down for you. All you need to take is a multimeter....

If these check out you may need too look at fuel pressure as well....but I have a feeling you will find the fault in the above.

SoCal Driver · SoCal Driver's Garage

Or a 12 volt test light. The kind that looks like a clear handle ice pick with wire and and aligator clip coming out the back. You can make one from a tail light bulb, some wire and a soldering iron.

bryanthompson · bryanthompson's Garage

hey guys. I just got back from tinkering with the car, but to no avail. I replaced the DME relay, which went smoothly. There's still no action from the fuel pump, at all. I checked and have power at the injectors and the coil. I didn't check the reference sensor with the spare spark plug, though. I'll try that Sunday when I take a whole bucketload of fuses to swap out. There were 2 fuses under the hood connected to wires on the positive battery terminal which were corroded pretty badly.

On a related note... does anyone else's wiring look like a bowl of spaghetti spilled under their dash? it's rediculous. There's a relay which appears to have jumpers from all the terminals back to the relay board. It's pretty much dangling there, which makes me nervous. It's a tannish/greyish relay with a fuse on the end. I'd like to take the car alarm [out] and hopefully clean up some of that wiring. I'm afraid the local P-Car mechanic did the electrical patching, which makes me want to not take it back to him. If you're not going to fix it right, don't bother. grr

Anywho, I'm pretty sure i'm going to end up putting a new fuel pump & filter on it. Already printed the clarks-garage procedure and am going to start ordering parts on monday.

Anyone have any more suggestions to make sure i'm not wasting money? I have a suspicion that the fuel pump that's on there now is possibly the origional one. Does it sound right to have a fuel pump last 227k miles? The clamps don't look like they've been run through for many many years and it just looks old.

SoCal Driver · SoCal Driver's Garage

You didn't use the jumper directly on the fuel pump so you don't really know if the fuel pump is good or bad. Unless you follow a structured testing plan you are just going to be throwing parts at it to no avail.

As to the wiring hanging down: It was running with the wiring hanging down before it quit. Don't think it's the wiring hanging down.

As to swapping out fuses: Just be concerned with the fuel pump fuse #2 (16 amps). None of the other fuses are for the DME injection part of the car as most is wired directly into the battery. The fuses at the battery are most likely for any stereo system that has been installed as the stock 83's don't have them. If someone has wired them into the stock electrical then yes you have other issues.

Power to the injectors indicates that the first set of contacts in the DME relay are working. Using a spare spark plug (you could have gone to an auto store and bought one if you weren't so busy with the girl friend) will tell you if your reference sensor is good.

bryanthompson · bryanthompson's Garage

I finally got my digital camera out and took some pictures of what the problem was. My rotor totally fried...

I put a new Dist. cap and rotor on from Pelican and it started right up.

Thanks for helping me out guys. Next time i'll have a better plan of action and won't aimlessly test random things

Like I said in another thread... all i needed was a little scolding from SoCal to get myself together and follow his plan. Thanks, SoCal

latunluvr · 05-23-2004, 09:06 AM

HOLY CRAP! That makes me want to go out and check my dist and rotor! When was the last time those things were changed? I seem to think that our cap and rotors are really high quality stuff as far as cap and rotors go. Not speaking from experience, but I'm thinkin you might have something else going on that caused it to burn up like that. Hopefully I'm wrong though. Anyone else have this kind of experience?

SoCal Driver · SoCal Driver's Garage

Was there a round plastic shield behind the rotor covering the large hole into the timing belt area? If not you need to get one. There is also a gasket that goes under the dist cap. These keep moisture out of the dist cap.

This failure is unique. Don't think you want to hear that. The only basic test that I could fathom that would find this is the spare spark plug in the wires. Would have to check all of the wires. This is a good example of why you use the spare spark plug test. It will find failures in the wires, dist, rotor.

idontknow · 05-23-2004, 03:01 PM

I had that same thing happen to my VW.

Check your plugs and wires. Mine did that cause it tried to fire the plugs w/ oil on them. There's supposed to be an embedded resistor in there. IIRC

idontknow · 05-23-2004, 03:06 PM

Stolen from air-cooled.net

"Another problem is that the Bosch rotor has a resistor in it, which WILL burn out in a short period of time if used with a high output ignition. You can dig it out, and solder a solid piece of brass in its place (it's between the tip and the cap contact area). "

bryanthompson · bryanthompson's Garage

my plug wires are farely new, but the old cap & rotor didn't look as high of quality of what i got from Pelican. the new Bosch stuff i got was way heavier and seemed to be made of different material. The fried rotor was more like a hard plastic, and the new one feels almost like ceramic. The dist. cap was a lot lighter and didn't have little protectors or something, not sure what they are, around the points. I can take more pics if you want to see that stuff.

Quote:

Was there a round plastic shield behind the rotor covering the large hole into the timing belt area?

SoCal, i don't think I have that plastic shield. I'll look for one of those tomorrow. When I put the new rotor on, i had to take the timing belt cover off to get to 2 bolts that cover the end of the camshaft. I was scared out of my mind, having to do that, but it worked out okay.

Anyway, I'm thinking the PO put cheap stuff on becuase what I have now is way higher quality. I will go out and check my plugs before going anywhere tomorrow though, just to make sure. What else could've caused the burnup?

SoCal Driver · SoCal Driver's Garage

Taking the top cover and the aluminum housing off is no big deal. This is sometimes the only way to get to the bolts for the rotor. Just make sure you used a bit of Locktite putting the screws back in. These have a nasty habit of coming loose and falling out.

As to your failure; cheap after market components is a strong possibility. Although it's been many years since I've seen a burnt up rotor and not on a stock 944. What condition are you spark plug wires in? Are they arcing to the engine?

When you get the plastic shield you will find a split in it from the outside to the inside. It's twists onto the rotor shaft. Don't need to take off the rotor.