Ok so I got a new computer harness for Vicky. And the engine is running great now. But, now, the ac doesn't work. When I put the climate controls on ac or max ac, the clutch engages, and then disengages in ignition run, not with the engine running. And the clutch will stay off unless I switched it to ignition accessories, where the clutch engages and stays on. What would cause the ac clutch to cycle on and off like that?
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Does the clutch engage with the engine running? The ECM uses the WOT cutout relay to disengage the compressor when cranking the car to reduce load. It won't kick the compressor on again until a few seconds after the engine starts.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers -
No, it doesn't. Here's the thing. I put the key in accessories mode, clutch engages. I put the key in run mode, no crank, the clutch engages, and then quickly disengages. The clutch does not reengage at all.Comment
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ECM is triggering the WOT relay for some reason. Have to determine why. Usually its seeing over 7/8 throttle, but its possible it will cut the AC if it sees the engine overheat. I guess it may also do it if there is no tach signal? Not entirely sure what other circumstances may trip that relay to engage.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousersComment
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Well it's not overheating, the ECT is showing the correct voltage values at operating temperature. How would I check for a tach signal? And would the computer being from an '87 towny make any difference?Originally posted by gadget73 View PostComment
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Ok. Self Test Shows code 18 when the car is running. Which is spout circuit open, or something going on with the TFI module. So is it possible that it is messing with my AC? I'm thinking that the harness, the original harness, since it looks like it was butchered at one point, caused the TFI module to crap itself or something, (but when running a code scan there were no problems, and the AC would work too.) causing the computers to die. I don't know, it's just a thought, I'm just looking for some confirmation, so I'm not rambling on about nothing. I'm kinda lost lol.
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Shorts in the wiring could cause ecm failure. Depends if it was actually shorted. Unwrap some of the harness and see if it looks like stuff came together in a bad way. The harness I pulled from my car was partially melted on the outside, but under the plastic wrapping it was totally intact. I thought it was causing a problem, but it turned out to be something totally unrelated.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousersComment
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Aparantly it's the computer. I wonder if it's cause of the year or something... well anyway, I'll get an '86 one and see what happens.Comment
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Jeez John. How many computers have you cycled through now?~David~
My 1987 Crown Victoria Coupe: The Brown Blob
My 2004 Mercedes Benz E320:The Benz
Originally posted by ootdega
My life is a long series of "nevermind" and "I guess not."
Originally posted by DerekTheGreat
But, that's just coming from me, this site's biggest pessimist. Best of luck
Originally posted by gadget73
my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.
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That would be number 5. Next one will be number six, and hopefully the last one. Car runs fine on number 5 but the ac doesn't work.Comment
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At least you are sorting out the problem little by little. Soon enough Vicky will be in tip top shape.~David~
My 1987 Crown Victoria Coupe: The Brown Blob
My 2004 Mercedes Benz E320:The Benz
Originally posted by ootdega
My life is a long series of "nevermind" and "I guess not."
Originally posted by DerekTheGreat
But, that's just coming from me, this site's biggest pessimist. Best of luck
Originally posted by gadget73
my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.
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Yep, hopefully this will be the last oneComment
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