Yaris - like it's going to stall

I have a 2008 Toyota Yaris automatic with 14,000 kilometers. About a month after the first year’s maintenance service, the engine started to slightly shudder while stopped at a light, as if it were going to stall. I brought it into the dealer, who gave it a cursory look. The service man said he couldn’t find anything, suggested I wait until I need to refill the gas tank…maybe I had gotten bad gas?..and then bring it back if it continues shuddering. I retanked and it’s still happening. Any idea what would cause this? Clogged filter? Problem with fuel pump? I haven’t a clue.

Unfortunately this can come from a lot of different sources. The 3 things that make the engine go are spark, fuel, and air. For each one of these there are any number of different things that could be related. I think that you’re going to need to a) wait for it to get worse so that it is easier to diagnose; b) press it with the dealer to take more than a cursory look.

If it isn’t under warranty, don’t take it to a dealer. Any good mechanic can handle it.

Is the check engine light on?

Thanks! It is still under warranty so the cost of fixing the problem is covered, but of course, you still have to pay for the time it will take for them to find the problem…at least that is what I’ve been told. No, the check engine light is not on.