1990 Blazer backfire at high speeds???
Hello Blazer fans!
I have a 1990 full size Chevy Blazer (142K miles) that has just started skipping and mildly backfiring upon acceleration. The truck idles fine and starts off from a stop fine but when I hit a big hill and have to put my foot in it the truck's engine feels like the timing is missing. Upon this hard acceleration it feels like it has no power and I can feel the engine shaking and stuttering and I can hear a backfire too. Funny thing is it does not do it on every hill. Sometimes it does it and sometimes it does'nt. And I can feel it going in and out from power to no power. It's almost like someone is flicking a switch that is screwing up my engine power.
I had the throttle position sensor, cap & rotor, fuel filter and new wires put on about 3 years ago. I just had the truck in the shop to replace rusted leaking fuel lines along the passenger side frame.
Does this sound like a sensor is broken again? I don't think it is a clogged fuel filter or it would do it all the time right?
Any ideas? Help will be greatly appreciated!