For those who are tired of wiggling the speed and reference connectors...
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For those who are tired of wiggling the speed and reference connectors...
Ever since I got my 951 back in 2003, it's been plagued by a no-start problem when the engine compartment temperature got a little high and when the humidity was at a certain level. I eventually learned that by wiggling the speed and reference connectors behind the intake manifold, I could "cure" the problem.
Now, our cars are getting up in years (20 in my case) and the wires running through the engine harness are showing their age. I don't have the time to rewire the whole harness but I figured I could at least redo the wiring from the connector plugs all the way to the DME.
I got some shielded (braided) two-pole wire from my local electronics store. Then I got some new three-pole AMP female connectors from EagleDay.com are well are some extra pin connectors, colored heat-shrink material, and some heat-resistant shielding loom.
I assembled my new "speed and reference harness" this afternoon and plugged everything in. The car fired up on the first attempt! Then I went from a drive to make sure that the engine compartment and the humidity would rise to the level that usually provoked the no-start situation. I came back home, let the car sit for about 10-15 minutes. When I cranked it after that short delay, it fired right up!. With the old wiring this delay and heat and humidity would have caused a no-start for sure.
I've restarted the car a couple of times since and it always starts right up. I'm now pretty confident that I've solved this nagging no-start problem!
Now, our cars are getting up in years (20 in my case) and the wires running through the engine harness are showing their age. I don't have the time to rewire the whole harness but I figured I could at least redo the wiring from the connector plugs all the way to the DME.
I got some shielded (braided) two-pole wire from my local electronics store. Then I got some new three-pole AMP female connectors from EagleDay.com are well are some extra pin connectors, colored heat-shrink material, and some heat-resistant shielding loom.
I assembled my new "speed and reference harness" this afternoon and plugged everything in. The car fired up on the first attempt! Then I went from a drive to make sure that the engine compartment and the humidity would rise to the level that usually provoked the no-start situation. I came back home, let the car sit for about 10-15 minutes. When I cranked it after that short delay, it fired right up!. With the old wiring this delay and heat and humidity would have caused a no-start for sure.
I've restarted the car a couple of times since and it always starts right up. I'm now pretty confident that I've solved this nagging no-start problem!
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951Porschiste, Congratulations on an excellent fix! I've been looking for 3 pole AMP male connectors to fix my broken sensor connectors, but alas, have come up emptyhanded. Any suggestions?
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So you basically replaced the reference sensor harness from DME to connector right?
How much did you get the shielded (braided) two-pole wire for? best price i found was $1 per foot.
How much did you get the shielded (braided) two-pole wire for? best price i found was $1 per foot.
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Originally Posted by hosrom_951
So you basically replaced the reference sensor harness from DME to connector right?
Originally Posted by hosrom_951
How much did you get the shielded (braided) two-pole wire for? best price i found was $1 per foot.
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Originally Posted by potent951turbo86
Great job, I know I have had the same problem as you on my old 951. Any chance you want to start making them for the rest of us?
Let me think about it
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Here's a picture of the speed and reference harness in place. Notice that I have removed the connectors from the holding bracket at the back of the intake manifold to make the picture clearer. The new harness is on the left and the wires from the sensors themselves are on the right of the picture. The wires are wrapped in heat-resistant sleaving. The wires are color-coded to make identification easier. Red goes to the reference sensor, yellow goes to the speed sensor.
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Originally Posted by Ski
Looks great! What pin removal tool or what did you use to get the pins out of the DME connector?
To remove the metal pins from the plastic connector, you need a special tool that will disengage the "locking tab" (see arrow in next picture):
I went to the local electronic store (ex-Radio-Shack, they are now called "The Source by Circuit City" in Canada) and could not find an adequate tool. So I decided to fabricate my own using a 1.5 mm allen wrench which I tapered down (see next picture) using a Dremel rotary tool.
Once I had the modified allen wrench, I then inserted this tool down the little plastic valley of the connector as seen in the next picture. This disengaged the "locking tab" and then I just had to pull on the wire to take it out.
And Voilà! Problem Solved!
#12
Three Wheelin'
So far I can only find 18AWG, 2 conductor, shielded wire with a temperature rating of 75C or 167F. Do you guys think this is ok for under a 951's hood? I've seen automotive wire that's rated for higher temps like 125Celcius, but it's not shielded or 2-pole. Andre, did your wire have a temp rating written on it? Thanks!!
Tom
'87 951
Tom
'87 951
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Originally Posted by 951Tom
So far I can only find 18AWG, 2 conductor, shielded wire with a temperature rating of 75C or 167F. Do you guys think this is ok for under a 951's hood? I've seen automotive wire that's rated for higher temps like 125Celcius, but it's not shielded or 2-pole. Andre, did your wire have a temp rating written on it? Thanks!!
Tom
'87 951
Tom
'87 951
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Originally Posted by 951Tom
So far I can only find 18AWG, 2 conductor, shielded wire with a temperature rating of 75C or 167F. Do you guys think this is ok for under a 951's hood? I've seen automotive wire that's rated for higher temps like 125Celcius, but it's not shielded or 2-pole. Andre, did your wire have a temp rating written on it? Thanks!!
Tom
'87 951
Tom
'87 951
That is what I used, at the bottom there. 2 conductor 22 gauge Milspec shielded. Good to 150 degrees C.
#15
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Andre and others that have done this,
I am able to remove a few pins with some effort, but I can't get most of the others out.
Mine have a locking feature on either side of the pin, whereas it sounds like the one you are describing only has a locking feature on one side? Looking at my pictures...does my setup match yours? If so, any suggestions?
There is one of these plastic retainers on each side of the connector:
Which leaves a DME connector that looks like:
TIA,
Adrial
I am able to remove a few pins with some effort, but I can't get most of the others out.
Mine have a locking feature on either side of the pin, whereas it sounds like the one you are describing only has a locking feature on one side? Looking at my pictures...does my setup match yours? If so, any suggestions?
There is one of these plastic retainers on each side of the connector:
Which leaves a DME connector that looks like:
TIA,
Adrial