pick1923

I have a 58 pu with a 2004 vortec. Ive driven this truck for a couple years with no problems. The other day I had a problem at idle. After running hard, it has rough idle and sputters off of idle. If I drive it easy for a short distance it smooths out. I changed the o2 sensors with no change. computer is not giving me a code. Any ideas? Thanks Mark

conan

iTrader: (5)

Have you tried cleaning the MAF ?

pick1923

I drove in some heavy rain when the problem started thats why I changed the o2 sensors. I thought maybe they got submerged. I'll try cleaning the maf. Wouldn't that throw a code? Thanks Mark

pick1923

Maf is clean

99huggerorangeZ

iTrader: (2)

possible intake gasket

pick1923

Got any ideas on how to check it without removing it. Thanks Mark

99huggerorangeZ

iTrader: (2)

spray throttle body cleaner around the sealing surface between the intake and the heads,also spray around tb gasket flange.

pick1923

I pulled the MAF and cleaned it, checked for vacuum leaks from air cleaner to the head and no luck. Same problem, rough idle after hard acceleration. Smooths out after short distance. I think it must be some sort of vacuum leak but it is undetectable so far. Thanks for the ideas, any others would be appreciated. Thanks Mark

wssix99

iTrader: (5)

Does the problem only happen when the engine is cold? If you idle after driving for a while is everything OK? If you re-start the engine while its still warm, does the problem come back?