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TECH TIP: Replace your old 944/964/993 DME relay

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Old 10-03-2012 | 02:28 PM
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Default TECH TIP: Replace your old 944/964/993 DME relay

We thought we would give a little heads up for any of you who may still have the older DME/Fuel pump relays in their 85 1/2 > 944's, 964's and 993's

If you still have the old relay in your car, replace it ASAP. These relay's can fail suddenly, cause intermittent rough running or bucking. Any time we get a car in the shop that still has the old part ( 944.615.227.00 ) PIC, we highly recommend replacing the part.

New part number: 993.615.227.01

OLD (Bad relay)

Old 10-03-2012 | 03:05 PM
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Is this a "new" type of failure or the same one that has been discussed on this forum about every other week for the past 10-12 years?
Old 10-03-2012 | 03:49 PM
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Originally Posted by TMc993
Is this a "new" type of failure or the same one that has been discussed on this forum about every other week for the past 10-12 years?
You'd be surprised how many people still don't know about this.
Old 10-03-2012 | 03:54 PM
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is it just a matter of taking the old one out and putting the new one in? Do you have to disconect the battery or reset anything?
Old 10-03-2012 | 04:04 PM
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Originally Posted by 996scott
is it just a matter of taking the old one out and putting the new one in? Do you have to disconect the battery or reset anything?
Yes. No need to disconnect the battery or anything else.
Old 10-03-2012 | 05:18 PM
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I just carry a spare...
Old 10-03-2012 | 05:28 PM
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Originally Posted by 177mph
I just carry a spare...
As do I. And I have a new 993 part number relay in my 968 which ittermittantly gives me problems.
Old 10-03-2012 | 05:38 PM
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I was not previously aware of this issue. I am going to take a look at mine and see what version it is.
Old 10-03-2012 | 11:59 PM
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Even if you get the "new" version, the fail rate on this part is pretty impressive (Do a "SEARCH" on words like "won't start," "stalling," "relay," etc. to get an idea). The best approach is to familiarize yourself with the location of the relay and keep a spare in your onboard toolkit. Replacement is a 5-minute task. There is also a test procedure that involves a three-wire jumper that can be useful in determining if your fuel pump relay has failed. SEARCH is your friend.
Old 10-04-2012 | 12:54 AM
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Originally Posted by TMc993
Even if you get the "new" version, the fail rate on this part is pretty impressive (Do a "SEARCH" on words like "won't start," "stalling," "relay," etc. to get an idea). The best approach is to familiarize yourself with the location of the relay and keep a spare in your onboard toolkit. Replacement is a 5-minute task. There is also a test procedure that involves a three-wire jumper that can be useful in determining if your fuel pump relay has failed. SEARCH is your friend.
What do you do with the other 4 min.?

Many of us also remove the relay when the car hasn't been started in a few weeks (or you just changed the oil) and turn the engine over for 10 - 20 sec. to let it build up oil pressure, put the relay back in it's slot, then start the car.
Old 10-04-2012 | 01:07 AM
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Originally Posted by MKS_Performance
If you still have the old relay in your car, replace it ASAP.
Talk about scare tactics! Gawd, there is a shop I'd trust.

Do you even know what fails on them? And do you with 100% certainty think the replacement won't fail for the same reason?

There is nothing wrong with the old original relay that some simple soldering of the relay board won't make it as reliable as can be.

In case you've never popped the cover on a DME relay...DME Relay - Failure and Repair

Last edited by IXLR8; 10-04-2012 at 10:35 PM.
Old 10-04-2012 | 07:21 AM
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Another tip: a fellow enthusiast recently managed to crack the underlying electrical board when replacing his relay. Therefore, do it with GENTLENESS.
Old 10-04-2012 | 11:05 AM
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Originally Posted by IXLR8
In case you've never popped the cover on a DME relay...DME Relay - Failure and Repair
Definitely one of the most useful posts ever...nice work...and thanks...
Old 10-04-2012 | 11:40 AM
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Originally Posted by Allen
Definitely one of the most useful posts ever...nice work...and thanks...
Glad I might have saved you some $$$ seeing how these have shot up in price.

I re-soldered my spare and new "993" DME relay as well, although I highly doubt I'll ever need it after after re-soldering my original "944" relay.
Old 10-04-2012 | 11:45 AM
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Not to be neurotic or paranoid.............but, years ago when I discovered my original DME and my spare had a 944 part number prefix, I bought a new one with a 993 prefix.

Now I have two spares and the original is still functioning.


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