TECH TIP: Replace your old 944/964/993 DME relay
#16
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I'll make sure to put the new relay on and make sure it works, then tug it inside the glove box.
#17
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That is all they should cost and are worth. I got one from Sunset Porsche for that price (discounted) a few years ago when I got my 993 and before I knew why they failed. Now they list for just over triple that from the dealer.
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#18
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My car is a 94 c2. Just did an oil change and had never heard any notable front end buzzing. After starting the car up, now have a pretty noticable buzz that sounds like its centered on the right side of the car astride the fuel tank.
Car drove fine for what its worth. Had been hoping sound would go away, but did not. Tank is a bit over half full. Search had been making me think fuel pump, but am curious based on the above comment.
#19
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The theory is that by cranking the car without the DME relay in, you can allow the oil to fill the filters and pressurize in the engine before its started. Crank until you see at least 1 bar pressure - some people do not like the continuous cranking, so you can do it with 5 second spurts. That way, when an oil change is done, you do not have that few seconds starting with empty filters and less oil in the engine. The same goes when the car sits - this cranking will re-wet all the moving surfaces, especially if the engine has sat for long periods of time.
Its has nothing to do with your buzzing. The fuel pump is just forward of the passengers feet, accessible from underneath - is that where the buzzing is coming from?
Try swapping the DME relay with your spare just in case the contact that powers the fuel pump is flakey or arcing..
Cheers,
Mike
Its has nothing to do with your buzzing. The fuel pump is just forward of the passengers feet, accessible from underneath - is that where the buzzing is coming from?
Try swapping the DME relay with your spare just in case the contact that powers the fuel pump is flakey or arcing..
Cheers,
Mike
#22
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I usually pre-fill my oil filters if they are mounted threaded side up. I do so on my BMW R1150 GS Adventure motorcycle. I can't remember if I do on the 993 engine oil filter.
#23
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Hi - I'm new to Porsche via my dementia suffering Mother In Law leaving me her 1989 944 to repair and sell. The car is in beautiful condition having been stored (not run) in a garage for over 10 years. So a few days ago, I finally got her to buy a battery but the thing doesn't start. I looked over all the possibilities to find there is no gas flow through the injector rail. But, more worrying than that, the car flattens the battery overnight! Welcome to Porsche ownership you sigh...Today I charged the battery and tried to concentrate on starting the car, I bought a haynes manual to try and locate the fuel pump. Why is it so difficult?????? Welcome to Porsche ownership you sigh... Well.. long story short, thanks to your site I was able to ascertain that Mom In Laws 1989 944 is an enigma seeing as there is very little written in print or on the web about it. I'm assuming the fuel pump is in the tank and the relay is called a DME. So, I've just ordered a new one from eBay. Wish me luck when it arrives.. Welcome to Porsche ownership you sigh...Oh, and I just checked the drain on the battery fully charged 14ma Welcome to Porsche ownership you sigh...!! Thanks for the insight
#24
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The theory is that by cranking the car without the DME relay in, you can allow the oil to fill the filters and pressurize in the engine before its started. Crank until you see at least 1 bar pressure - some people do not like the continuous cranking, so you can do it with 5 second spurts. That way, when an oil change is done, you do not have that few seconds starting with empty filters and less oil in the engine. The same goes when the car sits - this cranking will re-wet all the moving surfaces, especially if the engine has sat for long periods of time.
Its has nothing to do with your buzzing. The fuel pump is just forward of the passengers feet, accessible from underneath - is that where the buzzing is coming from?
Try swapping the DME relay with your spare just in case the contact that powers the fuel pump is flakey or arcing..
Cheers,
Mike
Its has nothing to do with your buzzing. The fuel pump is just forward of the passengers feet, accessible from underneath - is that where the buzzing is coming from?
Try swapping the DME relay with your spare just in case the contact that powers the fuel pump is flakey or arcing..
Cheers,
Mike