Bogged throttle response on hot days?

[1998tahoe]

I have a 98 tahoe 5.7 4x4 showing no ses on startup. On hot or humid days if I try to gun it it will hit 3k and just bog down as if it's struggling to go anywhere. I can literally have my foot to the floor and it will sit at 3k and go maybe 40. If I let off and easily coast up to a higher speed it will get up and go but still run funny as if there is a stumble. Fuel gauge does not work but pump was changed last year (very noisy at all times) not sure if that has anything to do with it. The last code the truck had was MAF sensor which I never changed I just reset the code and the light never came on again.

any ideas?

 

[SunlitComet]

verify proper operation of ses light at start-up and scan you pcm for active or stored codes. How specifically does the fuel gauge not work?

 

[ezdaar]

change fuel filter.. Run some Fuel system cleaner through it...
Run vehical down to almost empty, pour in 2 bottles then only put in like 10 gallons.
let it idle in driveway for like 30 mins, then let it sit for a few hours. then idle it again for 30 mins then go drive...

You trying to get a concentrated dose of cleaner.. Something is clogged up not allowing high fuel flow, which is required for slamming on the gass..
But will flow enough to get vehical up to speed if easing into the throttle...

You could have pinched the rubber fuel line in the tank and above the tank.. check them...

 

[1998tahoe]

verify proper operation of ses light at start-up and scan you pcm for active or stored codes. How specifically does the fuel gauge not work?

Gauge is pegged at empty this was with the old fuel pump as well as when the previous owner owned it. I go by the trip odometer for gas. When I got the truck It had a cluster from a 1995 silverado in it which made the temp gauge not work. I have since put a 1998 cluster in and the temp gauge works fine but still no fuel gauge. The SES light was on with the 1995 cluster but has never came on with the new cluster I put in.

You could have pinched the rubber fuel line in the tank and above the tank.. check them...

I'll give that a check before I do the rest. Also the truck cranks hard before starting. If I hold the key in on postition like you would in a diesel truck and let it sit for a moment it will start easily, if not it has a hard start esp when warm.

 

[SunlitComet]

Was the connector of the pump upgraded. when you leave the key on a 2-second pump prime is initiated. I would suggest you get a hold of a fuel pressure tester. Here is info on the gauge problem:

Gauge Stays at Empty This condition is generally caused by a short in the fuel tank wiring circuit.

1. Ensure fuel tank is full, then disconnect lead at fuel tank and turn ignition switch to the On position.
2. If gauge moves but not past full mark, replace fuel tank sending unit.
3. If gauge stays at empty, locate and repair short in circuit between gauge and fuel tank. If circuit is satisfactory, replace gauge.