97 2000-2100RPM Miss

[R.W.240]

Hello, Lately Ive been having a problem on one of my familys 1997 2500 Vortec 4x4 where at 2000-2100 RPM it has a huge Miss. it only happens at around 55 and 65 MPH when the throttle is maybe at just enough to hold the speed steady. It doesnt do anything while accelerating. The weird thing is one day driving home I hit a pot-hole and it started making a pin-wheel type noise it also felt faster and I could not get the miss to return. However, in two days the miss was back and actually a little worse.


If anyone can point me in the right direction it would be greatly appreaciated. Ive been told by a mechanic that its probably the fuel injector spider under the manifold but would like to see if anyone here has had this happen before I start to dig that deep into the engine. (Parts already Replaced - Fuel Filter and Spark Plugs .044 gap)

[kenny-1907]

Well for starters i personally would give it a full proper tune up. Replace the wires , cap and rotor, fuel filter and the plugs have been done as you said, clean the throttle body, either buy some of the real good injector cleaner (in a metal can) or take it in to have it done. I say the stuff in the can because it is alot better , it has stronger chemicals in it and this is why it is in a metal can. At least with these things done , you can absolutely rule them out as maybe being the cause. It is possible that one of the plug wires is grounding out and when you hit that pot hole it moved and was no longer groinding out. Weirder things have happened.