soontobeLS1

K, here it is: 99 sierra 5.3 Auto

When I push on the gas from a start or very close to it, the pedal goes down but the truck doesn't go anywhere, and then kicks in after a few seconds. It's like it wants to go, just doesn't. The rpm's don't climb. I can't spin the tires off the line.

The owner before me had the fuel pump replaced as well as fuel filter, my guess is he was chasing the problem down to no avail.

I have replaced plugs/wires and cleaned the air filter. It does have a k & n cold air intake (cleaned).

Don't think this is transmission related (but not sure), the truck has 250,000 KMS on it (150,000 miles?)

I have cleaned the MAF = no improvement.

One note, when I changed all the plugs, all of them had oil on the metal bolt piece/porcelain area.

If I am at speed and hammer it, she goes like a raped ape....

Any guesses???? Sensors??? PCM??? Pulling timing????

Thx anybody.

lt1pwr1

iTrader: (1)

So it is hesitating when you first give it gas? It sounds like a bad MAF to me. See if you can find a good tester somewhere. Most Silverados used the same MAF for many years I believe. Or get one at a junk yard for $50 or so.

Does it do this all the time?

soontobeLS1

ya, soon as i give it gas to go it hesitates...yesterday i had to get on the street in front of traffic and get boogying, sure i made the car behind me brake cuz the truck was going anywhere.

ccrook19

possibly a Throttle position sensor that is getting bad.. scan it with a lab scope or just use a volt meeter and sweep the sensor..