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engine stutters

alivepills

New member
i have a 2000 gp gt and untill a week ago it was my gramas car for 10 yrs.it has 111000 and has been taken care of well. but when i step on the gas the engine almost always hesitates for a split second and then takes off. the mechanics i have talked to seemed to think anything from fuel pressure to spark plugs to carbon deposits to vacumm leak somewhere. has anybody had a similar problem or have any ideas about where to start?
 


Maybe a vacuum leak somewhere.

Clean your MAF and throttlebody, change to fresh spark plugs (they are a 100,000 mile item - your car has not been "taken care of" that well if they haven't been changed by now), fresh spark plug wires, new fuel filter (30,000 mile item), Run a bottle of GM fuel system treatment in your gas tank, oil and filter change, fresh transmission filter (and top off the fluid).

After taking care of those normal maintenance items, and see if you still have an issue. It's stuff that should be done, regardless of whether you currently have a problem.
 
acording to the shop my grama took the car to there is a small leak in the intake. is this what may be causing this and what can happen if i dont get it fixed soon?
 


the spark plugs, fuel filter and tranny fluid were all done less than 10000 miles ago. i just cleaned the MAF and it improved performance somewhat but i am still having the stutering problem. this occurs only when i press hard on the gas or under high load. if i drive it like my grama there is no issues at all so far.
 
the spark plugs, fuel filter and tranny fluid were all done less than 10000 miles ago. i just cleaned the MAF and it improved performance somewhat but i am still having the stutering problem. this occurs only when i press hard on the gas or under high load. if i drive it like my grama there is no issues at all so far.

I am working on a car today that is doing the same thing. Clogged cat symptoms would be the manifolds glowing red after a long drive. However, if could be a misfire or coils... or fuel related.

If the plugs wires haven't been changed...that would be my first thing to do. Still does it after that? Check cat. If that's is fine check fuel pressure and/or get a new fuel filter.

No service engine soon codes?
 
there is a code for the o2 sensor. my g ma has probly spent a grand on o2 sensors during the life of the car. she finaly said **** it. could there be an underlying issue causing these to blow prematurely? could this be contributing to my problem?im running injector cleaner through it now but so far i see no difference
 
I am working on a car today that is doing the same thing. Clogged cat symptoms would be the manifolds glowing red after a long drive. However, if could be a misfire or coils... or fuel related.

If the plugs wires haven't been changed...that would be my first thing to do. Still does it after that? Check cat. If that's is fine check fuel pressure and/or get a new fuel filter.

No service engine soon codes?

Manifold doesnt have to glow red. Seen many cars where it was clogged but partially allowing exhaust gasses through. Easiest diy way to test is to get a laser thermometer and compare the pre and post catylic converter to see if there is a major temp difference. then take it for a back pressure test.

I still say clogged cat or fuel filter/fpr issues
 


Ok, the stuttering problem on the buick I worked on yesterday was related to plug and wires. Car had 60k on it with original plugs and wires. Once changed, the car was fine. No more stuttering on load.

To the OP, check your o2 wires to make sure none are melted/broken.
 
ok well i tested it and the only code that came up was p0140 what should i fix first? 02? fuel pressure regulator? and if the fuel pressure is good then should i still change it out?
 
ok well i tested it and the only code that came up was p0140 what should i fix first? 02? fuel pressure regulator? and if the fuel pressure is good then should i still change it out?

p0140 is related to your o2 sensor. I would trace the wires and make sure none are burn/cut..etc. Possibly a new o2 sensor. If you want to get a cheaper o2 sensor... look at rockauto.com Also, you can find coupon codes online to help.

My method of attack would be to get new spark plugs/wires to battle the stutter. If it still stutters... on to checking fuel pressure, maybe a new fuel filter..

The three things that all engines need ... Air, Fuel, Spark(Ignition).
 
hey i changed the plug wires. biigg difference didnt even notice it was still ****ed up for a while. it went from 70 percent stutter when i stepped on it. too maybe 10 percent. still an issue tho definetly. the coils are reading 6.3 ohms each, is this acceptable? should i reset the comp and see if it trips the ses again? will that hurt anything? how do i check the cat?
 


2 of the coil packs were rusted out and i used a wire brush on them untill they tested within specs but should i still replace them sence they were all rusted?
 
I typed a list of what misfires could be...

One of which was the harmonic balancer.

The cars are of the age where the rubber begins to fail.

If you've done wires, plugs, moved the injectors, ran injector cleaner, new fuel filter, swapped ICM's, spec'd the coils and its STILL not solved... I'd check the balancer.

Thats what was wrong with my car.
 
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