Hesitation While Accelerating
#1
Senior Member
Certified GM nut
Thread Starter
Hesitation While Accelerating
So Special Ed is actin up again. Go figure. I hit a bad pothole the other day, and ever since, its been hesitating while i try accelerating. When I accelerate from a light, if i push the throttle more that 1/4-1/2, the revs will drop and it'll accelerate much slower than it should.
When I'm driving at normal speed, 50km/h, and I accelerate WOT, it'll bog down for a second, then start accelerating, but it'll keep revving higher than it should and not shift until I let off the gas. When this happens, I can hear a hissing sound coming from either directly under me, or from the engine bay..its hard to tell.
It also seems like there is no top end power.. I went on the highway tonight to see if it would be okay to drive home next week (400kms) if I can't fix it before then, and I had to hold the gas pedal a lot further than I used to, just to barely hold it at 100km/h.
I'm pretty sure I damaged the exhaust when I hit that pothole as it is noticeably louder since then. Could that be causing this problem? It almost feels like there'* something plugging the intake. I haven't had a chance to look at the air filter as I was in class all day today, and had a couple assignments to do tonight. Is there anything or anywhere I could check?
I do have a rattle/vibration in my exhaust that'* been there for about a while, but it used to be intermittent. It seems like its occurring a lot more often now.. I have two videos of it that I took the other day:
From the side of the car, around the drivers' door:
[YT]http://www.youtube.com/watch?v=FigMQbMITQM[/YT]
From the rear
[YT]http://www.youtube.com/watch?v=_bjUf153GSE[/YT]
Thanks in advance guys,
Travis.
When I'm driving at normal speed, 50km/h, and I accelerate WOT, it'll bog down for a second, then start accelerating, but it'll keep revving higher than it should and not shift until I let off the gas. When this happens, I can hear a hissing sound coming from either directly under me, or from the engine bay..its hard to tell.
It also seems like there is no top end power.. I went on the highway tonight to see if it would be okay to drive home next week (400kms) if I can't fix it before then, and I had to hold the gas pedal a lot further than I used to, just to barely hold it at 100km/h.
I'm pretty sure I damaged the exhaust when I hit that pothole as it is noticeably louder since then. Could that be causing this problem? It almost feels like there'* something plugging the intake. I haven't had a chance to look at the air filter as I was in class all day today, and had a couple assignments to do tonight. Is there anything or anywhere I could check?
I do have a rattle/vibration in my exhaust that'* been there for about a while, but it used to be intermittent. It seems like its occurring a lot more often now.. I have two videos of it that I took the other day:
From the side of the car, around the drivers' door:
[YT]http://www.youtube.com/watch?v=FigMQbMITQM[/YT]
From the rear
[YT]http://www.youtube.com/watch?v=_bjUf153GSE[/YT]
Thanks in advance guys,
Travis.
#2
Senior Member
True Car Nut
a few thinks when the cat starts going the stuff starts clogging up the pathway you may have accelerated it, or any leak before the o2 is going to make it run bad. you may just have a leak or doughnut connection starting to go. sometimes the studs that hold the exhaust connections together rust and come apart
#4
Senior Member
True Car Nut
You may have hit an exhaust pipe and pinched it in, restricting the flow. It would give you the exact symptoms you are experiencing. Trace the exhaust system from front to back and look for damage. Been there, done that.
#5
Senior Member
Certified GM nut
Thread Starter
I just checked the exhaust. No signs of any kinks or pinches. I never really even noticed any holes in it either.. There is a build up of soot around rear bumper, by the exhaust tip, and on the tip itself. Is it possible that the cat can be plugged or almost plugged? I also checked the trans fluid too as per the directions in the owners manual, and that was good.
I took the intake apart to see if anything was obstructing it, and everything was clear.
Could a bad fpr cause this too? I took the vacuum hose off it, and there was a very faint smell of gas coming from it..
This thing really has me stumped
I took the intake apart to see if anything was obstructing it, and everything was clear.
Could a bad fpr cause this too? I took the vacuum hose off it, and there was a very faint smell of gas coming from it..
This thing really has me stumped
#6
i've had the same problem with my car for like 8 months and found no answer so i know how you feel. it'll hesitate at first and kind of jump forward but once the rpms get up a bit higher it smooths out and is fine, usually that'* all it does then it is fine, however sometimes it does stall as i try to go, then it usually cranks a bit till it starts back up. i need to replace the exhaust but dont have the money currently.
#7
Senior Member
Certified GM nut
Thread Starter
My problem seems a bit different..it seems like it gets worse as the rpms climb. When accelerating in second gear with the throttle more than 1/4-1/2 depressed, it feels like there'* no power, and it will not shift until I let off the gas pedal. When I do that, it don't seem like there'* any back pressure being built up.. But at lower rmps, like when first starting off, everything is fine, until probably around 1500-2000rpm (no tach, so just a guess) when it drops around 500 rpm or more, and becomes very sluggish accelerating.
#8
Senior Member
Certified GM nut
Certified GM nut
if you have a midas near you id take it there and jjust ask them to do their "free check" and tell them to focus around the exhaust and possibly tell them the symptoms. dont drop any money though. midas is about the most expensive place sans the dealer you could possibly go. if you find a cool guy theyll let you come into the shop and look for yourself. i usually just ask them if they can do the free check and can i come look for myself and they usually are ok with it.
its a little bit out of the way but its a whole lot easier to look at a car in a lighted garage on a lift than it is in a nasty driveway on your back lol.
that being said, im leaning towards the gasket where the manifold attaches to the rest of the exhaust. they love to fall apart and then you get that exhaust leak youre hearing. if the o2 sensor past that isnt getting the correct reading itll make your car run like crap.
its a little bit out of the way but its a whole lot easier to look at a car in a lighted garage on a lift than it is in a nasty driveway on your back lol.
that being said, im leaning towards the gasket where the manifold attaches to the rest of the exhaust. they love to fall apart and then you get that exhaust leak youre hearing. if the o2 sensor past that isnt getting the correct reading itll make your car run like crap.
#9
Senior Member
Certified GM nut
Thread Starter
There'* no Midas around here, unfortunately. But if I could park somewhere with enough room, i'd have no problem crawling under it and checking things out better myself. Its tough trying to do this kind of work when all you have is a tiny parking spot in the corner of a concrete retaining wall.
#10
Senior Member
Certified GM nut
Certified GM nut
There'* no Midas around here, unfortunately. But if I could park somewhere with enough room, i'd have no problem crawling under it and checking things out better myself. Its tough trying to do this kind of work when all you have is a tiny parking spot in the corner of a concrete retaining wall.
needless to say when the lease ends in june we're renting a house with a garage istead of a 1 bedroom apt for $800/mth. *end rant* lol