95 blazer-no acceleration

I am planning on getting a new truck this year, but I am keeping my 1995 Blazer for my son to drive while in high school.

The Blazer has only 110,000 miles on it.

It drives fine in town, but has NO acceleration on the highway, especially on inclines. (even a 10% grade causes me to go from 70 to 60 even though I have the accelerator to the floor). I recently changed plugs, wires, fuel and air filter, EVERYTHING. Today in a parking garage I noticed a rattle as I drove 10 mph.

Is it a compression problem and is its final days approaching? I really wanted my son to drive it for the next 2 yrs until he gets out of high school. HELP!

Go up one step on the gasoline octane. Take a fuel pressure gauge reading with the automatic transmission in DRIVE. If it’s a manual transmission, use a long fuel hose on the fuel pressure gauge and lay the gauge on the windshield (for easy viewing). Drive the truck slowly, with your foot on the brake (to load the engine) and observe the fuel pressure. If the fuel pressure falls too low, you’ve found your problem.

I would think with only a 110k miles it should be good for a lot longer.

Some questions might be:
Do you have, or ever had, a Check Engine Light illuminated?
Has the ignition timing ever been adjusted/checked? (This requires using the grounding plug.)

If this lack of power is a general sluggishness then that could point to several things.
One is a failing fuel pump and the other is a clogged catalytic converter.
I’m kind of leaning toward the latter. This could be checked with a vacuum gauge connected to the intake manifold.
As usual, I always recommend having a vacuum gauge around. They’re cheap, easy to use, and can tell you so much about what’s going on with an engine in just a few minutes.
The other option would be to unbolt the header pipe in front of the converter and annoy the neighbors during a test run. :slight_smile: