Engine Shudder

[mark293]

My 07 three door five speed has developed what I can best describe as an intermitent engine shudder at idle. I just assumed it was the electric fan cutting on an off but I can feel it throughout the vehicle. I have 65k on her and the mileage is a steady 40-42 mpg.

[yaris-me]

Run a good fuel system cleaner.:smile:

[ezhacker1]

do you have AC on? when it happens? What does the idle rpm go down to?

[UTVitz]

Interesting you say it has developed the shudder. Mine has done it since new, which mostly occurs during a/c cycling, but can happed as the idle adjusts after coming to a stop. Unless it starts to stall the car I wouldn't worry about it, try a different brand of gas. I've only ever used Chevron in this car and it's always happened, not all the time, not every day, just sometimes.

[Hershey]

Interesting you say it has developed the shudder. Mine has done it since new, which mostly occurs during a/c cycling, but can happed as the idle adjusts after coming to a stop. Unless it starts to stall the car I wouldn't worry about it, try a different brand of gas. I've only ever used Chevron in this car and it's always happened, not all the time, not every day, just sometimes.the '08 sedan has done this from the beginning . Notice it at an idle . Have used CHEVRON Techron fuel injector cleaner with no improvement . The car does get very good mileage though . So rather leave it at that .

[mark293]

Ill try a quality fuel system cleaner. I usually notice small things like that and Im sure a shudder that violent would have steered me clear of purchasing vehicle. It occurs whent he A/C is not on although Im sure it does it with A/C on. I have one of the digital tachs, so I will document and post what my engine rpm readings are. I guess the general consensus is dont worry about it.

[Hershey]

wonder if changing out the plugs could solve that . Just because they're iridium plugs that are able to last for 100,000 miles doesn't mean squat . I had the iridium plugs changed in a 2000 COROLLA at around 75,000 miles and gained better pickup along with some gain in mileage .