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  #1  
Old 08-06-2006, 03:59 PM
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Sr240sx Sr240sx is offline
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interesting drivetrain problem

Well, this consists of two questions.

Firstly, after the car's warmed up for a while, at about half throttle between 40-60 (that's where it's noticeable) the car shudders/hesitates HARD, until i depress the gas enough for it to downshift.

What i'm noticeing in the revband is that the engine is being reluctant to downshift, and just sticks at an rpm and hesitates like crazy.

Any ideas for what could cause this?

Second, after the car is warmed up (again) and i have the A/C on full bore, when i come to a stop, at completely random intervals, the car shudders. sometimes lightly, sometimes noticeably. and very randomly, without rhythm at all.

Again, any ideas?
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  #2  
Old 08-06-2006, 09:52 PM
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Quote:
Originally Posted by Sr240sx
Well, this consists of two questions.

Firstly, after the car's warmed up for a while, at about half throttle between 40-60 (that's where it's noticeable) the car shudders/hesitates HARD, until i depress the gas enough for it to downshift.

What i'm noticeing in the revband is that the engine is being reluctant to downshift, and just sticks at an rpm and hesitates like crazy.

Any ideas for what could cause this?

Second, after the car is warmed up (again) and i have the A/C on full bore, when i come to a stop, at completely random intervals, the car shudders. sometimes lightly, sometimes noticeably. and very randomly, without rhythm at all.

Again, any ideas?
(Second) = Increased load at idle. ---

Could be a throttle position sensor fault.

Otherwise, ignition, coil/s, plug/s.

P.S. Edit --- Also possible engine speed sensing problem?
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Last edited by Trevor; 08-06-2006 at 09:57 PM.
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  #3  
Old 08-06-2006, 09:52 PM
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Manarius Manarius is offline
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My Legacy had similar issues and it turned out to be the MAF. Reset the ECU and see if it still does it.
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Old 08-06-2006, 09:59 PM
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Quote:
Originally Posted by Manarius
My Legacy had similar issues and it turned out to be the MAF. Reset the ECU and see if it still does it.
Yes, I agree this is another likely cause.
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Old 08-08-2006, 12:31 AM
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And resetting the ecu involved what? Never had to screw with an ECU before, just swapped them out.
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  #6  
Old 08-08-2006, 05:25 AM
dcarrb dcarrb is offline
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Quote:
Originally Posted by Sr240sx
Firstly, after the car's warmed up for a while, at about half throttle between 40-60 (that's where it's noticeable) the car shudders/hesitates HARD, until i depress the gas enough for it to downshift.
If the torque converter on my teal locks-up when the engine's under load, say, on a moderate grade and in the speed range you mentioned, it lugs like dropping an anchor and begs a throttle-induced downshift. No shudder, but could this be what you're experiencing?

dcb
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  #7  
Old 08-08-2006, 01:58 PM
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it lugs AND shudders.
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  #8  
Old 08-08-2006, 02:12 PM
benjaminbreeze benjaminbreeze is offline
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I had this problem, or so it seems nearly the same. Have you had an oil leak? My coils were all saturated in oil and my car shuddered and was only drivable at around 3500rpms or higher (3rd gear highway). i replaced all coils and spark plugs and fixed the shuddering (I now idle at around 600 rpms but no shuddering)
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Old 08-08-2006, 02:25 PM
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the car had massive engine leaks all over the place. should I have the coil packs cleaned and the spark plugs replaced?
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  #10  
Old 08-08-2006, 02:30 PM
benjaminbreeze benjaminbreeze is offline
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Honestly id take it to a trusting shop (or a buddy of yours) if you can't and just check if it's the same problem...coils aren't the cheap. i think i found them for 150$ each if i remember correctly but the shop could only find them for 250$ each. I'm definately not mechanically inclined but it sounds like teh same problem that i had. My coils were so saturated they couldn't be just cleaned, they had to be replaced.
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Old 08-08-2006, 04:53 PM
oab_au oab_au is offline
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Quote:
Originally Posted by Sr240sx
the car had massive engine leaks all over the place. should I have the coil packs cleaned and the spark plugs replaced?
This statment;

"the car had massive engine leaks all over the place"

would point to a blocked PCV valve. This causes the crankcase to build up pressure to cause all the leaks.

Harvey.
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  #12  
Old 08-08-2006, 05:16 PM
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Aye, the valve was blocked. we cleaned it.
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Last edited by Sr240sx; 08-08-2006 at 05:44 PM.
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