Wasn't sure what category this would fall under.

First anomoly was when driving at about 65mph, decelerated to about 50mph. When pressing the gas the car wouldn't accelerate at first, almost like it wasn't receiving fuel, after a second or two it was fine.

Ran fine after that. On way home later, drove fine for about 15 miles, engine light came on but performance unaffected.

Now the light comes on often but the pattern I notice is always when I take my foot off the gas and decelerate, then the light comes on.

Also, today it did the same thing as first described but at a much lower speed, stepped on gas, no acceleration for about 2 seconds, then it is fine. Performance seems ok, although I doubt it is.

Since buying the car I have not changed the fuel filters but I run only Shell gas, try to buy only clean fuel.

Previous owner took good care of the car and always had dealership do the work.

I recently changed the O2 sensor, didn't help as the other symptoms prior to this are, idle bounces up/down if car is in neutral while warming up, car doesn't shift gears properly...hangs a bit at about 3k rpms, will change gears if I take foot off gas slightly.

Also changed the air filter, it was 2+ years old, not even very dirty but changed anyway.

Without getting it diagnosed, have any of you experienced these symptoms and can you recommend where to look first?


Thanks for any feedback.

 

When the check engine light turns on, that means the engine computer stored a code to help identify the problem. In the common DIY thread on top of the gen tech help forum, there is a link to checking engine codes that will help getting you started on identifying the problem. The engine computer has memory, so you can check for old codes even when the check engine light is turned off.

 

When you pull up the old codes let the forums know what they are...

Welcome to the HAF...

 

Ended up being code 11, idle mixture adjustment sensor. Originally it came up as O2 sensor but once battery was disconnected and reset the codes is when code 11 came up...must be triggering the O2 sensor...confusing it?

 

I would fix the code 11 first, since the O2 sensor code hasn't returned.