I've been having engine shaking at idle and in gear and when i take off, it is intermitantly rough thru low r.p.m.'s and smooths out in hire r.p.m.'s. i also have had some back firing and some lifter taps. Please help!!!!

 

Please help!!! My 95 z28 shakes in idol and in gear and runs rough at lower r.p.m.'s and runs better at higher r.p.m.'s. Some times it backfires with lifter taping at lower r.p.m.s.

 

Do u have a diagnostic program or a scanner? That would help u verify that ur o2 sensors r operating correctly, and some let u see if the low and high res signals are being sent from the opti. If not, then start with the usual, any work been done to the car lately? How r the plug wires? Check and make sure they're connected not just on the plug and especially @ the opti. Check for vac leaks, any ses codes? Did it just start all of a sudden? Loose vac lines, a leaky intake manifold, a bad ground, a bad opti, bad or clogged injector, lots of variables. When my car started doin that I went through everything, from the map to the cam lobes possibly getting worn flat, turned out to bethe connection @ the opti for #6 plug wire. Hope this helps

 

im having these exact problems was told it might be the opti going out. let me know if you find the problem.