Problem: When in closed loop the truck has what feels like a misfire or stutter upon a slight reduction in throttle pressure. For instance in freeway driving at any steady speed you would crest a small elevation and back slightly off the gas pedal to slow (maintain) to previous speed. Let’s say with cruise control on as the truck reduces throttle pressure to maintain set speed. Another example is letting off the gas after passing I get a buck or misfire. It feels to me that either spark or fuel just shuts down completely for less than a second. This issue is not present when I first start the truck and it’s running in open loop. It’s not the transmission.
I have no experience with fuel injection tuning so I sent a live data run to a programmer and got back a tune that runs better but did not elevate the problem. I’ve thrown to much money at replacing all sensors, distributer, plugs, wires and so called mechanics and still no fix. Not to mention tires, ball joints, fuel pump, tie rod ends, stereo, speakers etc. There are no vacuum leaks present that I can find. I want this to be my forever truck but it’s going to be hard to live with it if I can’t get it fixed.
1998 Chevy K1500 with a 8000 mile 5.7 short block replacement engine and new transmission. 129000 miles on the clock overall.
I’m in Yuma Arizona and willing to drive to a good tune (think scan tool) shop as we have none here.
Anyone here able or willing to help me?
I have no experience with fuel injection tuning so I sent a live data run to a programmer and got back a tune that runs better but did not elevate the problem. I’ve thrown to much money at replacing all sensors, distributer, plugs, wires and so called mechanics and still no fix. Not to mention tires, ball joints, fuel pump, tie rod ends, stereo, speakers etc. There are no vacuum leaks present that I can find. I want this to be my forever truck but it’s going to be hard to live with it if I can’t get it fixed.
1998 Chevy K1500 with a 8000 mile 5.7 short block replacement engine and new transmission. 129000 miles on the clock overall.
I’m in Yuma Arizona and willing to drive to a good tune (think scan tool) shop as we have none here.
Anyone here able or willing to help me?
