My h2 is not accelerating fast as it use to, I changed plugs and wire and still same issue. Perhaps I should change all Ignition Coils

Please add your thoughts

Thanks
JB

 

did you add a CAI ? Have you checked the MAF ?

 

If it's not misfiring I doubt it would be the coil. If it runs fine but is low on power I would check the fuel pressure and then check for plugged cats.

 

I'm not accelerating as fast as I used to either. I just attribute it to me being older and out of shape....

I see you posted in multiple threads about this. Better to just post once. Posting a bunch of times in new and/or bumping old threads with the same issue will annoy some people... Just saying.

Could be any number of things. Just throwing money/new parts at stuff until it resolves itself is certainly one method of going about it. Proper diagnostics tools can go a long ways too though but some can be expensive. Things like a Tech2 (expensive GM tool) can give vital information relating to possible stored codes and live running info on misses, sensor readings, etc. Fuel pressure test gauge can help you determine if its a fuel flow issue which could be a failing fuel pump, clogged fuel filter (only an external replaceable one on 03 and maybe 04 models), failing fuel pressure regulator, cracked air line to the pressure regulator. Clogged cats, dirty mass airflow sensor, failing o2 sensors, bad or failing spark plug wires or spark plugs (use ONLY AC Delco plugs), dirty throttle body...