car "bucking"... or something. help!
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OK, this might be a tough one to describe. First of all, its an '01 Trans Am - 6 speed. the ony "mods" are plugs/wires, gutted cats, frost mail order tune. And the car was fine for a good while after all of these, so I don't think they are part of the issue.
Anyway, the car seems hesitant, or like it kind of "bucks" under 1500 rpm. An example would be when I'm cruising at 60mph in 6th gear, well below 1500 rpm, and I try to give the car a little gas to maintain speed it kind of jerks. It is the worst feeling I have ever felt. Over 1500rpm the car seems to be fine. It doesn't really seem to be a problem in 1st gear (I'll pay more attention tomorrow). Also, the car might be idling slightly higher than normal.
I am at a complete loss with this one... any ideas guys? Thanks.
Anyway, the car seems hesitant, or like it kind of "bucks" under 1500 rpm. An example would be when I'm cruising at 60mph in 6th gear, well below 1500 rpm, and I try to give the car a little gas to maintain speed it kind of jerks. It is the worst feeling I have ever felt. Over 1500rpm the car seems to be fine. It doesn't really seem to be a problem in 1st gear (I'll pay more attention tomorrow). Also, the car might be idling slightly higher than normal.
I am at a complete loss with this one... any ideas guys? Thanks.
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Check for exhaust leaks. Mines did that a lot and it is annoying. I would check from the gaskets to the collector if you have LTs. I had flange leaks and didn't have a clue.
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I don't have LT's but I did have the exhaust apart while gutting the cats. I'll look at that too.
Thanks for the ideas guys, keep 'em coming.
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Is the SES (Service Engine Soon) light on or flashing?? If its flashing, you have a misfire. As suggested, I'd also clean the MAF. However, only use special MAF cleaner to do so, other products will damage the hot wire. CRC makes a product called "MAF Cleaner" specifically for that purpose, you can get it at most auto parts stores.
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Agreed. Remember, the plug wires "click" onto the spark plugs once, but "double click" onto the coils. Make sure the wires are all the way on the coils.
Is the SES (Service Engine Soon) light on or flashing?? If its flashing, you have a misfire. As suggested, I'd also clean the MAF. However, only use special MAF cleaner to do so, other products will damage the hot wire. CRC makes a product called "MAF Cleaner" specifically for that purpose, you can get it at most auto parts stores.
Is the SES (Service Engine Soon) light on or flashing?? If its flashing, you have a misfire. As suggested, I'd also clean the MAF. However, only use special MAF cleaner to do so, other products will damage the hot wire. CRC makes a product called "MAF Cleaner" specifically for that purpose, you can get it at most auto parts stores.
#9
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If its not your MAF it could be your 02 sensor(s). After my header install my car would hesitate sometimes in the lower RPMs and wasn't throwing codes. Replaced my two front 02 sensors and the car runs great now.
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also check for a crack in the EGR valve pipe which runs from your EGR solenoid to the EGR valve itself. I had a cracked one ages ago and she's jerk and buck on acceleration. Replaced the pipe and runs like a dream. ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
That is ofcourse for the LS1s without LS6 intake system
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That is ofcourse for the LS1s without LS6 intake system
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Alright guys, thanks for the list. Unfortunately I am extremely busy this semester between work and school, and I might not be able to start messing with the car until Wednesday evening. Think it will hurt to run it until then?
Thanks again, and I'm glad to hear that it is probably one of these small problems (I hope).
Thanks again, and I'm glad to hear that it is probably one of these small problems (I hope).
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wouldn't wanna run her too much mate, if its an oil pressure regulatory problem etc, it can stuff things up. on the flipside, if its just plugs or leads etc... won't do any harm... ur choice really
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Oh boy... so I can't even get my MAF out to clean it. I can't get to all the "torx" screws. Any hints/tip?? I've never tried to get to it before.
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Your not actually trying disassemble the maf itself are you? All you have to do is loosen the band clamps and take your maf out as one unit and spray the wires with the appropriate cleaner (i.e. Maf cleaner) and let it dry before reinstalling.
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only torx screws around the MAF are the ones ON the MAF... don't rip that apart mate... As said above, just undo the pipe clamps, take the MAF out and spray it... just make sure you use spay thats made for cleaning a MAF and not just any old spray...
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D'oh. That is what I get for working at sunset without a garage lol. I just assumed the entire thing had to come out. Good save guys, thanks.
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Mine did the exact same thing as you describe. No SES light or anything, new fuel filter/plugs wires didn't work. Took it to the chevy dealer and they said It was my #4 injector. I got a reman one and problem solved.
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I would recommend downshifting. Even when my car was stock it wouldn't enjoy me trying to accelerate at 60mph in sixth gear. I don't even shift to sixth unless I'm doing 75+. I do this due to the fact that if I do it any lower I believe a lot more heat is generated in the drive line also. I justify this by if I'm cruising on the interstate around 65-70 in 6th I get the spinning pilot bushing sound once I slow down and get off the interstate. I think the input shaft swells a little from the heat and then spins the pilot bushing.
I drive 60mph on my way to class everyday, in 5th gear its only 1900rpms, that is not spinning fast by any means.
I drive 60mph on my way to class everyday, in 5th gear its only 1900rpms, that is not spinning fast by any means.
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I would recommend downshifting. Even when my car was stock it wouldn't enjoy me trying to accelerate at 60mph in sixth gear. I don't even shift to sixth unless I'm doing 75+. I do this due to the fact that if I do it any lower I believe a lot more heat is generated in the drive line also. I justify this by if I'm cruising on the interstate around 65-70 in 6th I get the spinning pilot bushing sound once I slow down and get off the interstate. I think the input shaft swells a little from the heat and then spins the pilot bushing.
I drive 60mph on my way to class everyday, in 5th gear its only 1900rpms, that is not spinning fast by any means.
I drive 60mph on my way to class everyday, in 5th gear its only 1900rpms, that is not spinning fast by any means.
The only extra heat generated would be between the gears inside of the transmission, which is then dissipated by the transmission fluid, and then through the aluminum case.
You're not going to overheat the drivetrain by accelerating from a higher gear.