2003 H2 poor acceleration when cold & warm
 

Hi, I'm having poor acceleration when cold and even when it's warm. No trouble code light. Recent plugs, wires, fuel and air filter. I also cleaned the MAF with a MAF cleaner spray. I did notice a little oily/carbon build up at the throttle body. Haven't cleaned that yet, but will once this rain stops. While its cold, I press the pedal to like half to three quarters to the floor and horrible acceleration. As I start to let off the pedal it actually feels like its accelerating better. I do run fuel system cleaner through the system on occasion, use quality gas. I'm baffled. Thanks in advance for any suggestions, recommendations, etc. RJ03

Re: 2003 H2 poor acceleration when cold & warm
 

Unplug your maf sensor and try it, you will set codes but that will determine if maf is reading incorrectly. If its better you need maf sensor.

Re: 2003 H2 poor acceleration when cold & warm
 

Okay thanks HUMTECH. I'll drive it with the MAF unplugged. I better invest in a scan tool to reset light.

Re: 2003 H2 poor acceleration when cold & warm
 

HUMTECH, just curious, if I needed a new MAF wouldn't it triggered a code turning on the engine light? Or not necessarily? Thanks, RJ03

Re: 2003 H2 poor acceleration when cold & warm
 

Not always, seen many that cause lack of power yet the scan data readings are correct.

Re: 2003 H2 poor acceleration when cold & warm
 

Okay, had a feeling you were going to say that. Thanks for your help.

Re: 2003 H2 poor acceleration when cold & warm
 

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