944S Jerking / Hesitation
#1
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Join Date: Mar 2004
Location: Huntsville, AL
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I realize this topic has probably been beaten into the ground but I’m about to throw in my two cents as tonight I experienced an occurrence.
In short on a trip home this evening the car experienced some intermittent jerking for about 10 minutes.
Longer version:
I had to drive to Knoxville and back today … long story, but it put about 525 miles on the car (as I live in the Huntsville, Al area … but I digress). The trip to Knoxville was smooth as always. The majority of the trip back was also normal, however about half way back I filled up the car with gas and went along my merry way. Approx one hour later the car started to jerk intermittently for approx 10 minutes. After those 10 it didn’t hop, skip, or jump the rest of the hour drive to my house. So the point of this is I was wondering if this could be something other than the transmission?
Driving conditions:
1) It was unusually cold on the way back from Knoxville at approx 31 F. (at about 4:00 pm CST I was driving the part of the way that went through the Cumberland Plateau and my windshield was starting to ice up … so yeah, it was cold ... and I did _not_ go that way home as I went back via Chattanooga)
2) The section of road it started to hesitate and jerk on was a lot of little hills, so it was constant up down up down up down. I also had the cruise control set.
3) It performed the aforementioned actions randomly for approx 10 minuets.
My theory(s)
1) My transmission is slipping … (I hope not)
2) It was so bloody cold that the engine wasn’t at its usual temperature and thus was not performing optimally. (as the temp gauge was below the halfway mark, as it usually hangs around or just above the halfway mark for me most of the time)
3) While filling up the gas tank either some moisture snuck in off the nozzle, or the temperature of the gas going in was warmer than the gas already in my tank (or vice versa) thus creating moisture in the gas tank itself … as water in the fuel line may yield similar results?
---------------
Any insight that could be provided would be much appreciated. Thanks.
In short on a trip home this evening the car experienced some intermittent jerking for about 10 minutes.
Longer version:
I had to drive to Knoxville and back today … long story, but it put about 525 miles on the car (as I live in the Huntsville, Al area … but I digress). The trip to Knoxville was smooth as always. The majority of the trip back was also normal, however about half way back I filled up the car with gas and went along my merry way. Approx one hour later the car started to jerk intermittently for approx 10 minutes. After those 10 it didn’t hop, skip, or jump the rest of the hour drive to my house. So the point of this is I was wondering if this could be something other than the transmission?
Driving conditions:
1) It was unusually cold on the way back from Knoxville at approx 31 F. (at about 4:00 pm CST I was driving the part of the way that went through the Cumberland Plateau and my windshield was starting to ice up … so yeah, it was cold ... and I did _not_ go that way home as I went back via Chattanooga)
2) The section of road it started to hesitate and jerk on was a lot of little hills, so it was constant up down up down up down. I also had the cruise control set.
3) It performed the aforementioned actions randomly for approx 10 minuets.
My theory(s)
1) My transmission is slipping … (I hope not)
2) It was so bloody cold that the engine wasn’t at its usual temperature and thus was not performing optimally. (as the temp gauge was below the halfway mark, as it usually hangs around or just above the halfway mark for me most of the time)
3) While filling up the gas tank either some moisture snuck in off the nozzle, or the temperature of the gas going in was warmer than the gas already in my tank (or vice versa) thus creating moisture in the gas tank itself … as water in the fuel line may yield similar results?
---------------
Any insight that could be provided would be much appreciated. Thanks.
#2
Rennlist Member
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Here's my first guess, which is 16-valve 944 specific, btw:
Ignition Control Module. Located below the left headlight, mounted on a bracket next to the A/C drier. Swap it out for $50 or so, and report back.
Ignition Control Module. Located below the left headlight, mounted on a bracket next to the A/C drier. Swap it out for $50 or so, and report back.