Hesitation/Stuttering During Acceleration Worse When Cold
09-12-2017, 08:36 AM
#1
Thread Starter
Hesitation/Stuttering During Acceleration Worse When Cold
Alright - so after my previous attempt to sort this out I've finally narrowed down a better explanation of the issue, and have been able to consistently recreate it.
Car is an 06 with 141k on it. Basic bolt-ons, K&N intake, q300 exhaust etc.
So when accelerating with light to moderate throttle from 2-4k rpm I get stutters/jerks while accelerating. It seems to most commonly occur when I go from no throttle at all to light/moderate throttle. It almost feels like the engine/trans is struggling for grip. If I go full throttle it seems to rev up more smoothly, and I don't have an issue 5k+.
I've also noticed this is way way worse when the car is cold, so for the first 10-15 minutes or so after a cold start, the jerking and stuttering is much worse. Once the car is warmed up and has been driving a bit it's not as bad, but still there.
To give more detail on the issue. If I'm driving along at 4k rpm in 3rd and I lift and let the rpms drop to around 3k, then apply light to medium throttle, the car will jerk as it accelerates through back to 4k rpm. Same occurs 2k-3k.
More background:
This was happening about 10k miles or so ago, I then had my clutch replaced (ap1 flywheel, act PP, ap2 clutch), didn't have issues for 2-3k miles or so then it returned and has progressively gotten worse even than it was prior.
Does anyone have any ideas what might be causing this? Where I should check to help better diagnose the issue? It'd be great if I could at least narrow this down to being something like a fuel or misfire issue vs a transmission or clutch issue.
Could this be possibly throttle sensor related?
Car is an 06 with 141k on it. Basic bolt-ons, K&N intake, q300 exhaust etc.
So when accelerating with light to moderate throttle from 2-4k rpm I get stutters/jerks while accelerating. It seems to most commonly occur when I go from no throttle at all to light/moderate throttle. It almost feels like the engine/trans is struggling for grip. If I go full throttle it seems to rev up more smoothly, and I don't have an issue 5k+.
I've also noticed this is way way worse when the car is cold, so for the first 10-15 minutes or so after a cold start, the jerking and stuttering is much worse. Once the car is warmed up and has been driving a bit it's not as bad, but still there.
To give more detail on the issue. If I'm driving along at 4k rpm in 3rd and I lift and let the rpms drop to around 3k, then apply light to medium throttle, the car will jerk as it accelerates through back to 4k rpm. Same occurs 2k-3k.
More background:
This was happening about 10k miles or so ago, I then had my clutch replaced (ap1 flywheel, act PP, ap2 clutch), didn't have issues for 2-3k miles or so then it returned and has progressively gotten worse even than it was prior.
Does anyone have any ideas what might be causing this? Where I should check to help better diagnose the issue? It'd be great if I could at least narrow this down to being something like a fuel or misfire issue vs a transmission or clutch issue.
Could this be possibly throttle sensor related?
Last edited by rbtz; 09-12-2017 at 09:55 AM.
09-12-2017, 09:12 AM
#2
Alright - so after my previous attempt to sort this out I've finally narrowed down a better explanation of the issue, and have been able to consistently recreate it.
Car is an 06 with 141k on it. Basic bolt-ons, K&N intake, q300 exhaust etc.
So when accelerating with light to moderate throttle from 2-4k rpm I get stutters/jerks while accelerating. It seems to most commonly occur when I go from no throttle at all to light/moderate throttle. It almost feels like the engine/trans is struggling for grip. If I go full throttle it seems to rev up more smoothly, and I don't have an issue 5k+.
I've also noticed this is way way worse when the car is cold, so for the first 10-15 minutes or so after a cold start, the jerking and stuttering is much worse. Once the car is warmed up and has been driving a bit it's not as bad, but still there.
To give more detail on the issue. If I'm driving along at 4k rpm in 3rd and I lift and let the rpms drop to around 3k, then apply light to medium throttle, the car will jerk as it accelerates through back to 4k rpm. Same occurs 2k-3k.
More background:
This was happening about 10k miles or so ago, I then had my clutch replaced, didn't have issues for 2-3k miles or so then it returned and has progressively gotten worse even than it was prior.
Does anyone have any ideas what might be causing this? Where I should check to help better diagnose the issue? It'd be great if I could at least narrow this down to being something like a fuel or misfire issue vs a transmission or clutch issue.
Car is an 06 with 141k on it. Basic bolt-ons, K&N intake, q300 exhaust etc.
So when accelerating with light to moderate throttle from 2-4k rpm I get stutters/jerks while accelerating. It seems to most commonly occur when I go from no throttle at all to light/moderate throttle. It almost feels like the engine/trans is struggling for grip. If I go full throttle it seems to rev up more smoothly, and I don't have an issue 5k+.
I've also noticed this is way way worse when the car is cold, so for the first 10-15 minutes or so after a cold start, the jerking and stuttering is much worse. Once the car is warmed up and has been driving a bit it's not as bad, but still there.
To give more detail on the issue. If I'm driving along at 4k rpm in 3rd and I lift and let the rpms drop to around 3k, then apply light to medium throttle, the car will jerk as it accelerates through back to 4k rpm. Same occurs 2k-3k.
More background:
This was happening about 10k miles or so ago, I then had my clutch replaced, didn't have issues for 2-3k miles or so then it returned and has progressively gotten worse even than it was prior.
Does anyone have any ideas what might be causing this? Where I should check to help better diagnose the issue? It'd be great if I could at least narrow this down to being something like a fuel or misfire issue vs a transmission or clutch issue.
09-12-2017, 01:20 PM
#5
Thread Starter
Yeah I'm with you, I've experienced a slight hesitation or stutter before, much earlier on, but this is much worse, it will stutter/hesitate multiple times and in some cases (especially when cold) buck under light accel. Definitely leads me to believe that something is wrong, beyond the normal DBW quirks
09-13-2017, 05:10 AM
#6
Thread Starter
k so just an update - on a hunch I tried using the ol cruise control trick - first thing this morning when cold, set cruise around 25 and just held the cruise control accelerator up through 2500-4500 and didn't have a single hesitation. Did the exact same thing, smooth input with the actual throttle and got hesitation/stutters as per usual. So now thinking this has got to be a sensor issue, since I'm DBW I'm assuming replacing the APP could be the solution.
09-13-2017, 06:01 AM
#7
How many miles on the spark plugs?
Thanks!
Thanks!
Trending Topics
09-13-2017, 07:28 AM
#9
Thread Starter
About 20k - Pulled these as a check and they all looked good - made sure to torque to 18lbft
Definitely will do!
Definitely will do!
09-15-2017, 05:58 PM
#10
Thread Starter
great news folks - installed the new APP and the problem is completely gone. Not only this but my throttle feels 100x better.
Hope this helps anyone with a DBW car that has similar problems
Hope this helps anyone with a DBW car that has similar problems
Thread
Thread Starter
Forum
Replies
Last Post