98 Jimmy power peeve
Question:
I have an older Jimmy with 3.42 gears, 4.3L engine (CPI), and 4L60-E tranny. Power is PLENTIFUL!!! In regards to the fuel filter, I bought my truck used, and the fuel filter had never been changed, other than smoothing out a tiny bit, there was no other problem, made 2 3 hour trips on the same day, 2 times, no loss of power on the trip home, except for losing the EGR valve. – Hide quoted text — Show quoted text – > Tow-package ratio? You can get any ratio with the trailer hitch. Check in > your glovebox, and see if you have GU4, GU6, or GT4. If you have GU4, or > GU6, then you have faster gears, and this is your problem. From the sounds > of where your engine rpm is sitting, you do. Not much to do, besides change > gearsets – expensive! Find one with the 3.73’s (GT4), and try it. I own > one and it is fine. It is not a 350, but it works exactly for what we want > it to do. > Make sure that you are changing your fuel filter annually, as if it gets > plugged, it can overstress your fuel pump and lead to premature failure. > Almost makes me think this could be on of the things causing your loss of > power after 2-3 h. > 1998 GMC Jimmy (aka Blazer) – 4WD, 4.3L Vortec, tow-package axle ratio > Here’s my peeve: Lack of power-with faint slurping, gurgling, and mild > pinging-in the 1600 – 2000 RPM range. This occurs, for example, when > driving 50-60 mph (say, at 1700 RPM) coming to an uphill grade or > attempting to accelerate slightly by slowly depressing the accelerator. > The same can be experienced at lower speeds with similar RPM and load > increases. This annoying sound and feel-which is probably not > noticeable to the casual observer-diminishes and disappears when the > engine gets into the low to mid 2000’s. It is not a matter of engine > hesitation; just lack of power/torque. No lack of power is experienced > in the high 2000’s and above. 92 octane fuel used. I test drove > another new Jimmy and a used one with the same miles as mine, > experiencing the same phenomenon. It just doesn’t sound/feel right; I’d > like to get response from the engine without having to stomp on it. > What’s someone as particular as I to do? Might there be some after > market chip or spark booster that would help? > Another perhaps related issue is a VERY noticeable lack of acceleration > power at the end of a 2-3 hour highway drive in warm/hot weather. > -mat > Share what you know. Learn what you don’t.
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Response:
Tow-package ratio? You can get any ratio with the trailer hitch. Check in your glovebox, and see if you have GU4, GU6, or GT4. If you have GU4, or GU6, then you have faster gears, and this is your problem. From the sounds of where your engine rpm is sitting, you do. Not much to do, besides change gearsets – expensive! Find one with the 3.73’s (GT4), and try it. I own one and it is fine. It is not a 350, but it works exactly for what we want it to do. Make sure that you are changing your fuel filter annually, as if it gets plugged, it can overstress your fuel pump and lead to premature failure. Almost makes me think this could be on of the things causing your loss of power after 2-3 h. – Hide quoted text — Show quoted text – > 1998 GMC Jimmy (aka Blazer) – 4WD, 4.3L Vortec, tow-package axle ratio > Here’s my peeve: Lack of power-with faint slurping, gurgling, and mild > pinging-in the 1600 – 2000 RPM range. This occurs, for example, when > driving 50-60 mph (say, at 1700 RPM) coming to an uphill grade or > attempting to accelerate slightly by slowly depressing the accelerator. > The same can be experienced at lower speeds with similar RPM and load > increases. This annoying sound and feel-which is probably not > noticeable to the casual observer-diminishes and disappears when the > engine gets into the low to mid 2000’s. It is not a matter of engine > hesitation; just lack of power/torque. No lack of power is experienced > in the high 2000’s and above. 92 octane fuel used. I test drove > another new Jimmy and a used one with the same miles as mine, > experiencing the same phenomenon. It just doesn’t sound/feel right; I’d > like to get response from the engine without having to stomp on it. > What’s someone as particular as I to do? Might there be some after > market chip or spark booster that would help? > Another perhaps related issue is a VERY noticeable lack of acceleration > power at the end of a 2-3 hour highway drive in warm/hot weather. > -mat > Share what you know. Learn what you don’t.
Response:
1998 GMC Jimmy (aka Blazer) – 4WD, 4.3L Vortec, tow-package axle ratio Here’s my peeve: Lack of power-with faint slurping, gurgling, and mild pinging-in the 1600 – 2000 RPM range. This occurs, for example, when driving 50-60 mph (say, at 1700 RPM) coming to an uphill grade or attempting to accelerate slightly by slowly depressing the accelerator. The same can be experienced at lower speeds with similar RPM and load increases. This annoying sound and feel-which is probably not noticeable to the casual observer-diminishes and disappears when the engine gets into the low to mid 2000’s. It is not a matter of engine hesitation; just lack of power/torque. No lack of power is experienced in the high 2000’s and above. 92 octane fuel used. I test drove another new Jimmy and a used one with the same miles as mine, experiencing the same phenomenon. It just doesn’t sound/feel right; I’d like to get response from the engine without having to stomp on it. What’s someone as particular as I to do? Might there be some after market chip or spark booster that would help? Another perhaps related issue is a VERY noticeable lack of acceleration power at the end of a 2-3 hour highway drive in warm/hot weather. -mat Share what you know. Learn what you don’t.
