When I start up my car in the morning, it drives nice and smooth until the engine has warmed up. Then, when I press on the gas at lower rpms, the car stutters and struggles. During hot days especially, the car really has trouble. Can you guys give me suggestions as what the problem could be? Thanks.

 

tune up/// dunno try cleaning the air filter?

 

Are you using 10w30 instead of 5w30? Happened to me before...

 

I have I/H/E. Are you saying to clean the air filter on the intake? Yeah I am running 10w30 right now. Next oil change I will switch to 5w30. However, the guy I bought it from said that 10w40 was better than 10w30 for the car. It has a type R head on gsr block if that explains anything. Thanks for the input so far.

 

bump for help

 

dang that sucks, ITR head on GS-R block yields only 9.8:1 CR vs. stock GS-R of 10.0:1

 

10w40 is not necessay. sounds like it could be a distributor or something to do with ignition/timing. does the tach ever randomely bounce around or does the car ever cut out/misfire? i would do a tune up with plugs/wires cap, rotor, oil change, fuel filter and go from there

 

The tach idles pretty consistently. Thanks for the other advice Sumslapper.