Engine Studder on highway with partial thottle

[stl_ty]

i started trying to tune with a basic ultimate chip T1-15. I had one or two back fires and now the engine studders on the highway with partial thottle. it happens when crusing at about 50 then i give it about 50% tps and when it down shifts and goes up in rpm slowly then the studder happens. I have a narrowband afr right now and it studders with the engine. any thoughts on maybe did i blow out the reading of the o2 sensor? I put stock map back in and chip and problem is still happening.

 

[stl_ty]

Re: Engine Studder on highway with partial thottle

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[stl_ty]

Re: Engine Studder on highway with partial thottle

can anyone help? ask if you need to know more to get a better idea.

 

[stl_ty]

Re: Engine Studder on highway with partial thottle

I have replaced o2 sensor and checked vacuum lines and also replaced cap and rotor. no help any ideas. Does anyone think it could be timing or maybe the ignition control module.

 

[1madgumby]

Re: Engine Studder on highway with partial thottle

sounds like you have A Vac. line off somewere. try finding A hose off somewere. then let me know.

 

[Shift220]

Re: Engine Studder on highway with partial thottle

Sparkplug wires can definitely cause what your taking about so check those. As well as the rest of the ignition system.