'86 944 Auto rough idle...
07-10-2007, 03:33 PM
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'86 944 Auto rough idle...
Hello All,
Need help. Searched most places but can't find a solution.
My '86 944 NA Auto drives nice and all, but when slowing down to a traffic light, the engine will idle roughly and the whole car shakes.
I've done servicing, new belts, top overhaul, engine mounts, new fuel filter and have set the idle speed properly.
What could it be? The idle doesn't dip down to 600. It will drop to 800 when D or R is selected and then the shake will happen. I've tried setting the idle speed higher be no dice, when I shift to D or R, I will get that momentary rough shake.
Thanks!
Sprint.
Need help. Searched most places but can't find a solution.
My '86 944 NA Auto drives nice and all, but when slowing down to a traffic light, the engine will idle roughly and the whole car shakes.
I've done servicing, new belts, top overhaul, engine mounts, new fuel filter and have set the idle speed properly.
What could it be? The idle doesn't dip down to 600. It will drop to 800 when D or R is selected and then the shake will happen. I've tried setting the idle speed higher be no dice, when I shift to D or R, I will get that momentary rough shake.
Thanks!
Sprint.
07-19-2007, 05:02 AM
#3
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I had some bad vibrations at idle, but I knew I had a collapsed mount. Replaced that and it resolved issue, but I still get an occasional misfire? during idle. Just sounds like a little 'burp' in the exhaust every five seconds or so. I changed everything you mentioned recently, too except for the wires. I checked them out in the dark and saw a few leaks. When I misted (is that a word?...lol) them with water, the sparks were more significant, sooo i'm going to change out the wires and will report my results soon. They're about eight years old anyway. I also suspected a leaky injector but did a leak-down test and it held proper pressure. Might have a bad spray pattern though, 'cause I cracked a hat on one awhile ago, and just epoxied it back together. Might be coming back to haunt me now.
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07-21-2007, 02:23 PM
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07-21-2007, 04:56 PM
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It defiantly sounds like the damnper/ flex plate. If it is the vacuum lines or anything else let me know because I have the same problem, but I'm 99% sure its the flex plate.
07-25-2007, 02:35 AM
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Originally Posted by MrDude
It defiantly sounds like the damnper/ flex plate. If it is the vacuum lines or anything else let me know because I have the same problem, but I'm 99% sure its the flex plate.
What can be wrong with the flex plate? That is what auto cars have as opposed to a flywheel on a manual? Also known as the drive plate? Can it go south?
Sprint.
07-25-2007, 08:26 AM
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Yes absolutely....More of a torque converter than flywheel. They break down similiar to the older rubber clutch disc and very common on an auto. First thing to check out when thinking of buying one(auto) and very pricey to replace.
07-25-2007, 04:52 PM
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Originally Posted by dgz924s
Yes absolutely....More of a torque converter than flywheel. They break down similiar to the older rubber clutch disc and very common on an auto. First thing to check out when thinking of buying one(auto) and very pricey to replace.
Any part number?
Thanks!
Sprint.
07-25-2007, 07:50 PM
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Had bad does it run in park at about 1800-2500 rpm?
if it has little coughs or drop offs I found that my AFM needed the track ajusted.
The other thing I had was really mucked up injectors...
swapped injectors with a blown motor and the car perked right up and ran smooooooth...
Plus I had new wires, belts, plugs, cap, rotor all done before the AFM and the injectors....
Good luck and look for the cheap problems first LOL....
Vacuum is definetly a major possibility...
JC
if it has little coughs or drop offs I found that my AFM needed the track ajusted.
The other thing I had was really mucked up injectors...
swapped injectors with a blown motor and the car perked right up and ran smooooooth...
Plus I had new wires, belts, plugs, cap, rotor all done before the AFM and the injectors....
Good luck and look for the cheap problems first LOL....
Vacuum is definetly a major possibility...
JC