Twice The Fun

ok i had a problem b4 with the car jumping around in rpms, it would drop them and raise them at its own free will.....the water pump was leaking, onto the opti, so i replaced both, thinking the opti was messed up.........well it still does it, what else could it be, any ideas???

badass383

If you aren't throwing codes go for simple. How much of the simple routine maintenance stuff have you checked like check and/or clean IAC, check/or clean EGR, clean the MAF wire, had your injectors cleaned or replaced the O2's if they are older than 50000 miles, changed the fuel filter?

I see a lot of cars in here that are running a bit lean and ECM keeps trying to compensate for it.

First thing I do is clean the injectors through the fuel rail with 3M cleaner.

It's probably a good time to do the maintenance you might have putting off.

Let us know

Twice The Fun

thanx i'll give all that a try

Twice The Fun

still doing it after all this....

cleaned air filter
unplugged MAF just to see if that was the problem, it wasnt
replaced cracked intake elbow w/ 1LE
blocked off EGR

after all this i gave up....spent too much money not finding the problem,

my only guesses left are plugs, which i may have fried in a nitrous backfire....which may have started all this, who knows.....

the other guess is tranny problems w/ the new converter

i havent checked injectors, 02s, IAC, but already have replaced the fuel filter tho

weirdest thing is it doesnt throw any codes...damn LT1s,

Gripenfelter

Do you have any coolant in your oil or vice versa?

Does it do this when the car is warm at idle?

Twice The Fun

i dont think i have any coolant/oil mixture..they both leak by themseleves, lol

it usully does this while driving at warmed up engine temps

z28Power

If you are having random jumping of RPMs like that, another possibility would be the coil and/or coil wire. Maybe they aren't getting the charge across correctly. I dunno how much these parts are, I understand that you have spent a lot of money already.

Do you know anybody in the area with an fbody? You could just use their coil and coilwire to see if the problem goes away?

Twice The Fun

got tired of ****ing with it, and finally sent it to the local GM dealership, i have spent too much money anyways, might as well add more to the list to fix it.....they prolly will check plugs/wires first, i told them that was my thought, but i will mention the coil also