Engine hesitation

[newvibe]

I own a 5-speed base Vibe.I have seen a few discussions on engine hesitation, but I could not tell how the issues were resolved. During moderate acceleration from 3000 RPM to 5000 RPM (nowhere near the red line), I can sometimes feel a lull in the acceleration. It might happen a few times during a single pass on a highway. Not a stall in acceleration, but a dip in the power.Is this something people are putting up with? I haven't experimented with A/C off yet to see if that is the cause, leeching power from the engine during flatter parts of the power curve. I am using regular octane gas.Did anyone else run into similar problems and find a definitive fix? Thanks.

[joatmon]

I have a base 5 speed and haven't noticed this problem. I'll have to pay more attention. This problem has been mentioned here before, but I don't remember anyone coming up with any fixes for it.The dyno curve for the Injen CAI on a Matrix XR (the first dyno chart for a base engine that I could find) shows that HP/torque was not a nice smooth curve across the RPM range It might just be the way the engine is, and maybe there's nothing to done about it.

[pmh013]

newvibe, where are you in the world? I had a similar problem with a very long, sordid story http://forums.genvibe.com/zerothread?id=2894&page=1 .In any case, I would take it in to the dealership. If you can (and you practically must), go out with the technician. You drive, and let them run the diagnostics, so they can get a read-out of what the car is doing. If you notice it gets worse when winter hits (if you in fact get winter where you live), then you've got a plugged catalytic converter.If you don't already, keep extremely accurate records of your fuelling ... which station & what your milage is at. If you can prove a drop in fuel economy, then there's definitely something wrong.Keep us posted!!

[MrRich]

I have same problem when my A/C is on.When I am passing somebody and shift back to 3rd,and it is always at 80 Km/h.When the A/C is off everything is nice and smooth.