I have an ignition problem!! HELP!

[davidhaggerty]

I have had a problem w/ mu truck keeping a stable idle after I push in the clutch. the engine RPM's will drop and bobble around @ about 250 or lower and then the idle will stablize at about 750. I was told by a mechanic that I needed a new O2 sensor and that should solve the problem. I replaced the O2 sensor and I still have problems with the idle staying stable after I have been running. Also, recently, I have had to run the started pretty hard to get it to turn over. There seems to be a blue cloud when it finally kicks over. Any ideas on whats wrong are welcome.

[2rz]

ok first of all what year is your truck? second if your truck is fuel injected check your (tps) throtle position sensore if is good and if calburated I don't know what to tell you. third if it doesn't start when is cold it could be your cold start injector. now don't take my answer for sure I'm just giving you a sudjestion of what it could be ok

[pickupgirl]

Carburators suck, so if you have one, I suggested kicking it. Stock carbs on any car I have found only lead to problems. Aftermarket carbs such as weber or holley have like four components and nothing can really go that wrong. This is just from my experiance. I have a stock carb on my truck at the moment. The float bowl never stays at its stock line, which basically means I'm bobbing in and out of traffic. But your problem doesnt sound like a carb problem. Or a fuel injected problem. Doesnt the evil blue smoke mean oil?

[eroc13]

if it happens when its started up its most likely the valve seals.blue or gray smoke is oil...