Im sure it has been talked about here many times, so here we go again,

I have a 94 Z28. Original Plugs, wires, Optispark, 02 sensor. Sometimes, not all the time, I get some stumbling at low RPMS, like before it downshifts. It hasnt done it in 2 weeks, and now all of a sudden it was back today. It comes and goes. What would be the deal? I know the plugs and wires should be changed anyways, but wouldnt bad plugs or wires be and all the time deal? oh yeah, when its in its stumbling mode, it runs fine when u get in higher RPMS.
90K on the car also..
Rob

 

clean your maf?

 

Is their any special way to do that? Any instructions?

Rob

 

alcohol, q-tip, caution.

as soon as you wipe a part off, you'll see how dirty the whole thing is. also, you can test to see if that is even the problem by unplugging it and see if it runs better.

im assuming you have an oiled, cotton air filter instead of the original paper. if you still have paper then your maf probably isnt even dirty.

 

to tell you the truth, when I got the car a month or so ago, it had the stock air filter in it. I replaced it with a cheap $10 FRAM...

Rob

 

i'd be willing to bet is an EGR issue. how many miles are on the vehicle?

 

90,000 miles

 

i would bet wires 90% of these so called opti problems are from wires. ok maybe 70%

 

Remove MAF sensor and blast the wire with some "O2 Safe" TB or Carb cleaner. I did this to my explorer last night and it got rid of a YEAR OLD stumbling problem. Talk about a quick fix. Dirt and K&N oil really do mess the wire up.