Over the past couple of months my 01 Rodeo V6 4x4 has been hestitating when first started in the morning and the engine is still cold. It seems to be better after the engine warms up. It also seems the engine doesn't accelerate very smoothly? It surges mildly when accelerating quickly. Any ideas?

How long has it been sens you spark plugs have been changed? Air filter? There is a sensor in the intake that detects the temp of the air running into the intake, and from there the computer will give a adustment to the air / fuel mixture until the engine warms. Could be the sensor, but most likely if you have not changed the plugs in a few years that will give you a stumble in cold starts.

I have never changed the plugs, but with 95k on them, I will do that tomorrow when I get the brakes done. I will post the results. Thank you!

I had the plugs replaced and so far so good. It drives quite nicely now and the hesitation appears to be gone. Thank you Keefbikes!

What plugs did you use?

'01 has ion sensing ignition and uses the spark plugs as sensors so it needs certain plugs to be installed. If the system doesnt like them you will get a check engine light with random misfire codes. Apparently you used ones it likes or you would have gotten the codes by now, so just curious which ones they are.

My rodeo has always had a hesitation since I bought it. Even with new plugs, filters, clean egr and pcv valves etc I've never been able to figure it out. Just learned to live with it so far.

NGK iridium plugs were used.

Glad it was an easy problem to fix. Thanks for keeping us up on your progress.[img]smileys/smiley10.gif[/img]

Update- It is 75% better. There was a little hesitation this morning. Before the plug change, it would almost sputter to a halt if I left without warming it up. It's much improved, but it is still hestitating a bit.