Chevrolet Silverado Repair Question
Silverado runs rough when engine is warm
Asked by bomber2782Answer
If its the MAF will it set a code?
it may but it may not. it depends how far the sensor is out of range. but because it happens after it warms up i would start there.
I replaced the MAF sensor. The "service engine soon" light went out. I let it warm up to about 200 degrees or so, drove it for about 15 minutes and it was driving a lot better than before. The light came back on though, 'system too lean, bank 1.' It only seems to do this when I give it a lot of throttle. I put some fuel system cleaner in the fuel when this whole thign started last week, you think this might be causing it to be sluggish? Or what about another fuel filter, or even fuel pump? Are there more advanced ways of diagnosing this truck sinece there are no codes if I take it into a shop? I thought I would save money by doign it this way, but I have spent about $400 so far, and its still not fixed. Thanks- Eric.
this should be hooked up to a scanner so you can see live data as it happens to better diagnose the problem. before throwing more money at it.
Do you have any idea how much a shop might charge me for something like that?
I have a 99 Silverado 5.3 as well. I recently had it in the shop to have them check a couple of diagnostic trouble codes and was charged $84. (North Dallas)
I tested the fuel pressure tonight. I get 18-20psi with the key on-off a few times. When running I get between 15-22psi. What next, new fuel pump or regulator? Thanks, Eric.
Have you cleaned the inside of the intake port on your throttle body?
Pressure is definitely low. Should be about 60 psi I think. Low pressure points to fuel pump rather than regulator. Can you hear the pump whine when you turn the key over without starting engine?