My car, which is a never-ending source of headaches for me, has a new issue!

 

When I step on the gas, it hesitates a few times. It wants to go go go, but something is making it feel like it's missing, or hesitating.

 

I recently changed my knock sensor (yay! the CEL is finally off!), but I'm pretty sure it was doing this before I changed the sensor.

 

So what are my primary suspects? Vacuum leak? another sensor (o2)? Maybe something else? My car has been thru a lot since I bought it back in September '10, but it's just about all good now. This is my only problem, and I can't wait to get it resolved.

 

any ideas?

Model and year would help.

 

Have you reset the ECU by disconnecting the battery for 15 minutes?

 

Fuel filter?

 

How many miles on the T-Belt, if it jumped a tooth or 2 you could have timing issues.

 

Is this an erratic problem or constant issue?

 

You could trace all the vacuum lines and connections to make sure everything is correctly hooked up.

Model and year would help.

 

Oh, sorry! I thought I had included that info. It's a 98 OBW with a 2.5 engine. Recently (last Nov) had the head gasket, water pump, timing belt, 1,000 seals and o-rings replaced. Engine runs very well and doesn't leak a drop.

 

Have you reset the ECU by disconnecting the battery for 15 minutes?

 

No, I haven't tried that. I'd rather not because getting my keyless entry to work was a bear! ..but I will as a last resort.

 

Fuel filter?

 

Nope. I haven't changed it. I should probably do that soon.

 

How many miles on the T-Belt, if it jumped a tooth or 2 you could have timing issues.

 

Again, it's only 9 months old. Not even 10k miles.

 

Is this an erratic problem or constant issue?

 

the problem is mainly within he first 15 minutes of driving. It eventually goes away, but it happens every day.

 

You could trace all the vacuum lines and connections to make sure everything is correctly hooked up.

 

You know, I seem to remember this problem starting after I washed my engine. I wonder if I knocked something loose. I'll poke around.

mine did the same kind of thing after washing the engine, water got somthing wet it eventually cleaned it self out, you could try compressed air to the plug wires and such see if it fixes it

it's been weeks, and the heat has been crazy. I don't think there's any lingering water.

Did you check your spark plug resistance?

If your front 02 sensor has not been replaced in the last 40k miles, you might suspect that. Symptom will usually occur under load when engine is warm.