Low Power

Festus611 · December 29, 2007

Hey Guys. I was looking for a little help with my 93 suburban. It is a K1500 1/2 ton. 350. OK here is the problem. In the morning it has been running really rough. At startup it will run right way but will not stay running without a little help. Once I begin driving if I give it any more than a light press on the pedal it will begin to buck on me. This continues until the engine warms up about 3 miles of driving or so. After that if I look in my mirror and give it some more pedal I get a puff of black smoke. This smoke will continue until I either really get moving or lay off of it. Also if I try to hard on it, it will pretty much lose all power. If I let up it runs fine. Finally, when driving on the highway, if I try to pass and go more than about half with the pedal I get the puff and cloud of black smoke again. Any thought or suggestions would be greatly appreciated. Thanks again.

Festus611

Ranger · December 29, 2007

Might be tuneup time...Oil, filter, plugs, wires, dist cap/rotor, etc. The carburetor may be in need of a rebuild also.

Festus611 · December 29, 2007

Might be tuneup time...Oil, filter, plugs, wires, dist cap/rotor, etc. The carburetor may be in need of a rebuild also.

Done all that within the last 3 months, with the exception of the throttle body cleanup. I did clean it about a year ago though. I will check it again. Any thoughts on the Idle Air Control or the Throttle position Sensor being bad? That had been mentioned to me by a friend. Thanks.

Ranger · December 29, 2007

Possible, I don't have a lot of experience with TBI but it may need adjustment...Does it throw any Check Engine lights?

Genuinefine409 · December 29, 2007

Did you ever change the fuel presure regulator? Black smoke is extra fuel so maybe it could be going a little bad and giving you extra fuel pressure. Not sure if that'll cure you i just remember my brother changing his one time. I think jegs even sells an adjustable one.