2003 H2 Question

[PewterPower]

I have a 2003 H2 LUX with 88K miles on it. Recently replaced plugs with NGK and a new set of 7.5mm wires....new brake pads and both front hub/bearings have been replaced. I also cleaned the air sensor using electronic parts cleaner. Since replacing the plugs might have confused the computer, I also unhooked the battery for 30 minutes and then reconnected it.

When I start the engine cold, it seems to 'sputter' or jump....and the tach goes up and down....once it warms up, it seems to run better. I had my local shop check and there are no error codes. He checked the Fuel pressure and some other things and said that he doesn't see anything wrong.

The last time that I pulled a trailer (about 3K lbs) I had no power....

Any ideas ? Suggestions?

[mdoyle]

I've got a 2003 also and based on past experience I always stick with the AC Delco OEM plugs from the dealer. On another truck (Chevy Duallie) I tried the Bosch Platnium and there was a noticable reduction in power.

Years ago I ran a car at the strip and we would swap out plugs for different heat ranges and read the insulators as part of our tuning along with jet changes, ect. The main thing I learned through that process is that different plugs will make a very measurable difference in performance.

[IRA51]

the right heat range NGK plugs will be as good as the AC delco plugs.if the idle is going up and down I would take a hard look at your mass air sensor,they can be bad and not throw a code. I wouldnt hurt to decarb the engine and clean the throttlebody also.

[Adam in CO]

Mine does that in the cold.