2005 GMC Envoy Engine Pickup and performance lags

SAMEH_166

MEMBER
2005 GMC ENVOY

Engine Performance problem
2005 GMC Envoy 6 cyl All Wheel Drive Automatic 75K miles

Hi,

For the past 3 months my car has lost its usual pickup. Last month, I changed the oil, oil filter, air filter, but still to no avail there is lag when I push the gas.

However a little improvement was felt when I refilled my gas tank along with these performance solution ( to clearn carburetor engine system etc. ). Once a mechanic told me there is some dirt on spark plugs. Though I changed the plugs like only 4 months ago.

I have to travel long distance next week, and am worried about the engine performance.

Any help would be appreciated.

Regards,
Sameh

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,192 POSTS

Hi:
First, has the check engine light ever come on? Next, has fuel pressure been tested? And finally, a partially plugged caylatic converter will cause a loss of power. At night when the car is hot and running, check the converter to see if it is glowing red hot. IF so, it's plugged.

Here is a how to for checking fuel pump pressure:

https://www.2carpros.com/how_to/how_to_check_fuel_pressure.htm

Let me know what you find.