Trailblazer issue

ALM518

MEMBER
2002 CHEVROLET TRAILBLAZER
6 CYL
2WD
AUTOMATIC
160,000 MILES

Whenever I turn my A/C on and slow down, around 15 mph or less, it shakes really bad like it's losing power and will shut off on me if I stop. I went to the mechanic and he said there was oil build up from a leak up in the engine cover and cleaned it out. It stopped shutting off, but now even if the A/C is off and I slow down or stop it shakes real bad and feels like it's going to turn off. I was told I need a new engine, is this true or is there something that could be done to it?

1 Reply

CARADIODOC

MECHANIC
33,742 POSTS

Time for a second opinion. Sounds like you could have nothing more than a misfire condition due to spark plugs and wires, or it could be as serious as a burned valve and low compression in one or more cylinders. That hardly calls for an entire engine. A valve job takes care of bad valves.

GM also has a huge problem with their injectors causing running problems although what you described sounds a lot worse than what injectors can cause. Chrysler buys their injectors in matched sets and problems with them are just about unheard of. GM takes a handful of injectors out of a bin and throws them into an engine without matching them for flow rates. It is real common to have a couple of cylinders running too rich and a couple to be too lean. The lean ones cause too much unburned oxygen to show up in the exhaust where it is detected as a lean condition, then the Engine Computer commands more fuel to all of the cylinders. Buying a matched set of rebuilt injectors will solve that problem and greatly improve horsepower and fuel mileage.

If spark plugs and wires don't help, the next step is to perform a compression test. If any cylinders are low, a cylinder leakage test can identify the cause of the low compression.