ok, here we go, i had this prob with my rpm's not exceeding 2000 to 3000 when merging into expressway or when ever i put my foot to the floor. i thought it was a tune up, so i got accel cap rotor, ignition coil, 8.8mm wires and ac delco plugs(the aluminum ones that are supposed to run cooler). did the tune up, to it for a spin, was 100% better for about 20 mins, then i went to my house parked it for like 30 mins, went to drive it again, and it was fine then the rpm thing happened again. i have yet to pull the plugs again, i thought it was the carbon build up cause it started to get better then it got really worse, it wouldnt go above 1500 rpm for like 10 miles. then it went back to what it was before. i have no clue what it could be, i made sure the wires didnt get burned and fouled up, could it be the plugs because the thread length was longer on the new ones but i thought that was because they were supposed to run "cooler". i am totally lost, and the only thing i can trace it to is the ecm, or could it be the hypertech chip? any info or a point in the right direction is great

 

Do you have a Catalitic converter in your exhaust system? If so, it may be plugged...look under the car at night with the engine running and warmed up. See if its glowing..

 

yeah i have all the emmisions stuff on my car, i only let it on so i can pass emissions when i get the letter, but i thought if you remove the converter the car wont run because the air system will be looking for the converter, or will it not affect it at all??

 

get a high flow converter, catco has one for about $120, get it at summitracing

 

Does it rev freely in park?

Try hitting the cat with a mallet or a something that won't damage it and see if you hear anything rattling around in it. (this would sound funny out of context, eh?)

You could unbolt it and see if it performs better. If you could monitor your fuel pressure while revving, that may help to eliminate a fuel problem.

 

Dont remove it!!! Try Rezin's method...if that doesnt work ...Buy new!

 

this is weird, but it makes sense, my friend sugessted my IAC was bad and told me to unhook it, and it works fine, i have an SES but i have no trouble out of the car, i need to reset it once in a while, but other wise it runs like it should, and i do need a new cat cause i does slightly glow, but i will worry about that in the next day or so, but thats, it was great help, but know if some one comes along with the same prob it is because the ECM is reading the IAC is open and wont let the car throttle correctly

 

ok, it ran good for about 10 days and it started again, i need a new knock sensor clip, its coming in the mail, but i have it rigged for right now, the engine now only does it when it gets hot, and when i shut it down it wont start for about 15 to 20 mins, then it starts and acts all wierd with the rev prob, i was told it could be the ignition module, or something else like fuel injectors, any suggestions on this one now?????

 

Fuel pressure, as in clogged fuel filter or weak pump.

I have a Bonneville that would lose power when hot. Fuel pump was getting weak, problem solved with new pump.

 

Try a new ignition module. Sometimes when they get hot they won't work and your car won't start. When it cools off a little it'll start again.