Engine bucking A LOT
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Car: '86 Trans Am
Engine: 305 TPI
Engine bucking A LOT
Yesterday I noticed that my car started bucking whenever I did a full acceleration, and soon it started bucking heavily all the time. Now it's impossible to drive it, implying you can even start it because of poor idle.
Sometimes I can drive half a mile normally and then it just starts bucking like hell again and sets off the SES light.
Diagnostics say it's error code 44 - Lean exhaust.
I did a lot of work on the engine last winter which means it could be a million different things. But it did run properly for months.
A month ago I started noticing bad idle every now and then but thought it was probably a small vacuum leak until yesterday. (There's a small gap between the air cleaner and the MAF sensor and I've spent hours trying to assemble the damn thing and there's always a gap.)
Also, the O2 sensor wire had to be lengthened due to new headers but if this was the problem, why did it work just fine for months?
Today I heard that the use of oiled K&N filters can break your MAF:
http://forums.automobilemag.com/70/6...you-thousands/
This is the first time I have used a K&N filter so I can't rule this out either.
Sometimes I can drive half a mile normally and then it just starts bucking like hell again and sets off the SES light.
Diagnostics say it's error code 44 - Lean exhaust.
I did a lot of work on the engine last winter which means it could be a million different things. But it did run properly for months.
A month ago I started noticing bad idle every now and then but thought it was probably a small vacuum leak until yesterday. (There's a small gap between the air cleaner and the MAF sensor and I've spent hours trying to assemble the damn thing and there's always a gap.)
Also, the O2 sensor wire had to be lengthened due to new headers but if this was the problem, why did it work just fine for months?
Today I heard that the use of oiled K&N filters can break your MAF:
http://forums.automobilemag.com/70/6...you-thousands/
This is the first time I have used a K&N filter so I can't rule this out either.
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Car: '86 Trans Am
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Car: '86 Trans Am
Engine: 305 TPI
Re: Engine bucking A LOT
Replacing the O2 sensor seems to have helped with the bucking but the engine still pretty much dies every time I stop for traffic lights.
Unless I put it in parking gear.
Why is this?
Unless I put it in parking gear.
Why is this?
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Car: 1989 IROC & ROLL-Z
Engine: L98 Vortec FIRST TPI
Transmission: T56, Mech Speedo
Axle/Gears: G92 J65 3.27
Re: Engine bucking A LOT
Did you check the basics?
Check base timing, perhaps distributor came loose?
Do a good fuel system test, note pressures.
If a sensor was faulty IE reading values outside its specified range, the computer would pick it up and tell you via SES light or better yet, datalogging.
I would pay attention to the fact that it ran fine for months and got progressively worse.
Check base timing, perhaps distributor came loose?
Do a good fuel system test, note pressures.
If a sensor was faulty IE reading values outside its specified range, the computer would pick it up and tell you via SES light or better yet, datalogging.
I would pay attention to the fact that it ran fine for months and got progressively worse.
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