924Board.org

[JSilverman]

Well I went to go pick up my new car from FL over the weekend. I made it to SC where the car was shut off at a rest stop. It never fired up again. It would crank but not turn over. We tested for spark (using a screw driver) and did not get anything. I have been doing some research and it seems the car may have a bad DME relay. I did not check it while I was with the car and I had to be at work yesterday so I had to leave it in SC. Another possible problem is the POS alarm someone had installed, but the symptoms soudn remakable similar to the DME relay. The car started fine when it was cold, but after a few hours of driving and being turned off it would not fire up. Is there anythign else I should be looking for as the culprit. When I go back for the car ill have a multi meter to do some testing, is there anything else I should look for?

[gohim]

Did you remove the distributor cap and spin the motor to verify that the timing belt is intact and the ignition timing is correct?

[JSilverman]

We did not. The distributor cap was removed to make sure that the contacts were ok, but we did not spin the engine. The car ran great for several hundred miles with no problems until it was shut off at that point. I would think that it would have been very obvious if the timing belt broke. (pistons slapping the valves cant sound pretty, plus the belt is realtively new with only 10k on it.) Since it ran fine for a few hundred miles I would also think that the timing is ok as well but its something else worth checking.

[JSilverman]

Ok, I heard from the shop that the car was left with and they got it running. They bypassed the DME relay and it started. They did test the relay and it was good so there is some other problem. The car runs and fires every time according to the mechanic. Does anyone have any idea what could be wrong?

[gohim]

Bad solder connections inside of the brain box are pretty common on cars this age. this could explain the sometimes it starts and sometimes it doesn't.

Bypassing the DME (fuel pump) relay does not cure anything in these cars, if the problem is the brain box.

Have the shop reinstall the DME relay. I bet the car will start and run (for a while) with the original DME relay installed. This would probably verify that the brain box has a bad connection.

You may be able to verify that the problem is in the brain box by running the car till the engine stops. then banging on the brain box (located under the passenger carpet under the dashboard) to see if the car will then restart.

You say that the belts have 10K miles on them? How many months is that, and did you have the shop check the belt tension while they were in there inspecting the belts? Belts must be inspected and retensioned at the first 2K miles (because of belt stretch) and again every 10K miles or year, if you don't replace them, and every 3 years, even if they have not reached 30K miles, and every 30K miles.

[JSilverman]

Thanks for the tips!!! I am going to get the car this weekend, and when I get back Ill try reinstalling the relay. As far as the belts go I can only go by the documentation provided by the previous owner. The car has ~85k and the belts and pump were done at 75k. I dont have the paperwork with me right now but from what I remember that was just under a year ago (10 months or so) The belts were re-tensioned at 2k. I have seen many recomendations on the belt service, but most seem to agree that 30k replacements are in order(or 3 years), then retension at 2k and at 15k. The shop that has the car now was an emergency stop. It was the closest garage to where the car stopped running. I have an appointment with a local shop to retension the belts next week and to make sure everything else is in order.

Out of curiosity, why the short interval on the timing belts for these cars? Every other car Ive owned that had an interference engine went on a 5 yr 60k timing belt schedule. Is there somethign in the design of the timing belt that makes it more prone to failure? Or is it simply a matter of timingbelts being less expensive to replace than bent valves? Thanks again.

[Paul]

My experience has been that the belts last 30,000 to 70,000 miles or 3 to 10 years.

IMO, if you want to ignore the belts after the retensioning, change them at 3 years and 30,000 miles.

IMO, if you check them at every oil change and respond promptly to any leaks or noises, you can make them last longer.

I refuse to replace things such as the front seals, the water pump, the balance shaft seals, etc. until I actually notice a problem. If you're not experienced on working on these cars and don't know them inside out, IMO stick to the 3 years, 30,000 miles.

I also do not use the "tool" so I guess I'm not worthly of anyone's respect, and by some people's recommendation, I should not work on these cars.

My signature says it all.
_________________
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.

[gohim]

Paul, in previous discussions you have stated that you stand behind the work, advise and opinions from your shop.

Are you saying that if I pay you to change my belts, and to do my oil changes, you and your shop will cover any damages caused by failed components up to 60K miles?

I would be pissed if one of the front oil seals started to leak at 12K miles, necessitating a teardown to replace the oil seals after I changed the belts. And what about a water pump failure? If you change the belts, and tell me that the water pump will be good until the next belt change at 60K miles, and the pump fails in 15K miles, are you going to pay for the belts and the valves if the water pump leaks and the belt fails in less than 60K miles?

That's a heck of warranty, what do you charge for a belt change?

[gohim]

Paul, in previous discussions you have stated that you stand behind the work, advise and opinions from your shop.

Are you saying that if I pay you to change my belts, and to do my oil changes, you and your shop will cover any damages caused by failed components up to 60K miles?

I would be pissed if one of the front oil seals started to leak at 12K miles, necessitating a teardown to replace the oil seals after I changed the belts. And what about a water pump failure? If you change the belts, and tell me that the water pump will be good until the next belt change at 60K miles, and the pump fails in 15K miles, are you going to pay for the belts and the valves if the water pump leaks and the belt fails in less than 60K miles?

That's a heck of warranty, what do you charge for a belt change?

[Paul]

My comments above are based on what I do for my personal cars.

They are relevant only to those who share the knowledge and love of these cars as I do. And the secret (and maybe, sick) desire for something to break so I can tear it apart.

In regards to work for hire, I like most everyone else who has been successful in repairing these cars for others, recommend that everything be replaced every 3 years or 30,000 miles. It's kind of self serving since the mark up in the parts is a major source of the profit for this kind of job.

If someone doesn't follow this recommendation, they are responsible for future repairs.

Maybe it's customer service, or maybe some think it's a mechanic looking for more work, but I usually will take a few minutes to take a look at the belts, if they are fine the customer doesn't even know I looked, if not I make a phone call.

That said, I don't do a whole lot of customer work anymore, my regular job and my cars are more than enough to keep me busy.

Has anyone had a new Porsche water pump fail in less than 6 years or 60,000 miles? I've never seen one.
_________________
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.

[JSilverman]

Well the car made it home. Turned it on and off about a half dozen times. Now I just have to get the jumpers out and figure out what the problem is. Let the fun begin