Hesitation around 2-3k
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Okay, so, I seem to have some hesitation around 2-3k rpm on acceleration. Or, is it just that the car picks up so much around 3k rpm that it feels like it is hesitating?
Car is '96 C2 with 60k miles. No mods that I know of.
I cleaned the ISV and I want to clean the MAF sensor, but, I can't seem to find a how to anywhere. It doesn't seem like it should be too hard.
I did get a P1123 CEL once in driving rain, but, it went away and never came back. Not sure if that is a symptom or not.
any thoughts?
Bob
Car is '96 C2 with 60k miles. No mods that I know of.
I cleaned the ISV and I want to clean the MAF sensor, but, I can't seem to find a how to anywhere. It doesn't seem like it should be too hard.
I did get a P1123 CEL once in driving rain, but, it went away and never came back. Not sure if that is a symptom or not.
any thoughts?
Bob
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I have a 1997 993 C2 (tiptronic) where I have a slight hiccup/hesitation around 3K when accelerating in second gear. It sounds almost as if the car wants to "shift" for a split second, and then continues accelerating. Someone suggested I service my transmission. Others have said it could be an electrical signal or an issue with a Bosch controller. Did you resolve your hesitation?
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I have a 1997 993 C2 (tiptronic) where I have a slight hiccup/hesitation around 3K when accelerating in second gear. It sounds almost as if the car wants to "shift" for a split second, and then continues accelerating. Someone suggested I service my transmission. Others have said it could be an electrical signal or an issue with a Bosch controller. Did you resolve your hesitation?
Good news, the 2nd gear "hiccup" is normal. That is the torque converter locking up.
Push down on that right pedal harder and you barely feel it
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Back to Bob's problem...
Bob, should be smooth acceleration though the RPMs... cleaning MAF won't hurt. CRC makes a MAF cleaner.
If the 60K service hasn't been done you might just start there and see what happens.
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Hi,
60k service was done 11/06. I did clean the MAF, but, it didn't help. I have also replaced the O2 sensors pre-cat.
I hadn't really noticed the hesitation in a while, (I have a new born and I don't notice much these days). I did notice it today. I am thinking about trying to trace all the vacuum lines and see if they are all okay.
Where would water get that could cause an 1124 code? again, this could be unrelated.
Bob
60k service was done 11/06. I did clean the MAF, but, it didn't help. I have also replaced the O2 sensors pre-cat.
I hadn't really noticed the hesitation in a while, (I have a new born and I don't notice much these days). I did notice it today. I am thinking about trying to trace all the vacuum lines and see if they are all okay.
Where would water get that could cause an 1124 code? again, this could be unrelated.
Bob
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Check the distributor belt and the ignition leads too. After any work, disconnect the battery to re-set the system as often the DME will continue to compensate for errors that it has logged that aren't neccessarily there anymore.
Worth a shot.
Worth a shot.
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#8
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Interesting about the MAF needing cleaning. . . .
Not that I want to hi-jack the thread or anything, but, now and then I experience a slight hesitation or lack of torque feeling in acceleration around 4300-4500 RPM.
It's not a lot, kinda like the AC compressor kicking in, but the AC is off. As I hit 4600-4800 it's gone and the engine pulls strong. It's like a little flat spot in the torque curve which isn't there most of the time so I know it's not supposed to be there.
It doesn't happen all the time. Just now and then.
So, any ideas for this one? Does the MAF sensor need cleaning? I had the car in for some work on the rear cam covers a couple months ago and the mechanic said the dist belts looked to be in good shape. . . Anything else that is easy to try? Is the MAF cleaning an easy DIY?
TIA
Not that I want to hi-jack the thread or anything, but, now and then I experience a slight hesitation or lack of torque feeling in acceleration around 4300-4500 RPM.
It's not a lot, kinda like the AC compressor kicking in, but the AC is off. As I hit 4600-4800 it's gone and the engine pulls strong. It's like a little flat spot in the torque curve which isn't there most of the time so I know it's not supposed to be there.
It doesn't happen all the time. Just now and then.
So, any ideas for this one? Does the MAF sensor need cleaning? I had the car in for some work on the rear cam covers a couple months ago and the mechanic said the dist belts looked to be in good shape. . . Anything else that is easy to try? Is the MAF cleaning an easy DIY?
TIA
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I had a hesitation too, due to bad plug wires. Replaced them and it went away. I didn't see arcing but the covers were split on a couple of the exhaust-side wires, found them while changing valve cover gaskets.
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95FL993CAB, I'd give it a go. make sure you have the best fuel that you would normally use and leave disconnected for a short time. When you reconnect, drive immediately as you would normally don't let in sit in the garage warming up.
Couldn't hurt and costs nothing.
Couldn't hurt and costs nothing.
#12
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wow...i have been tormented with the same problem for a while now...
everything started when i changed the small T hose in the left rear of the engine..i started to notice that i didnt have the same feeling in accelaration.had my mech change the distributors and rotors and i still dont feel it being the same...it stalls like you all mentioned. my mech said i should change my plug wires but its kind of strange for that to be the problem and very coincidental since the car flew before i changed that stupid little 8$ hose!! and i checked the vacuum hose and everything seems fine also checked the 2 top actuators next to the varioram. will try the disconect battery strategy...
everything started when i changed the small T hose in the left rear of the engine..i started to notice that i didnt have the same feeling in accelaration.had my mech change the distributors and rotors and i still dont feel it being the same...it stalls like you all mentioned. my mech said i should change my plug wires but its kind of strange for that to be the problem and very coincidental since the car flew before i changed that stupid little 8$ hose!! and i checked the vacuum hose and everything seems fine also checked the 2 top actuators next to the varioram. will try the disconect battery strategy...
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Remember that if you insert a vacuum line too far, it will get blocked off. IIRC, Porsche discussed that in a TSB. I'm not sure which lines you replaced but you might check for that.