Power Loss I have a '98 Chevy Tahoe, just had a long block installed, changed the trans fluid, throttle pos. sensor, cleaned the MAS, changed the knock sensor, no engine codes. My problem is a significant power loss from 4000 rpm and above. If I start out from a dead stop and run it at full throttle the engine keeps winding loses power at 4000 but will rev higher and then takes FOREVER to shift into 2nd gear. If I'm traveling up a hill or mountain and I kick it down into passing gear, it will not pick up speed, can hear the engine winding or revving but its like I ran into a wall. Also, I drove a friend of my mines 96 with a vortec and it will haul compared to mine, did really notice a difference in exhaust tone also between the two. Please help, I'm at a loss here, thinkin it may be the cats startin to clog up?
Cars & Trucks - Chevrolet - Tahoe - 1998 Chevrolet Tahoe
Answers & Comments
If your old engine ran real bad with oil passing through your exhaust more than likely the catalytic converter is bad
I would check and see if the long block you had purchased is the correct one for your truck. I have no idea where you bought it for its not mentioned. I seen plenty of engines tagged wrong in the past 30 years and it did create problems for each one installed
I'm assuming the old engine was bad. That bad engine probably sent a lot of oil/unburnt fuel into the catalytic converter. Its probably clogged (there are a few catalytic converter cleaners on the market) or fried and you'll need to replace it.