Oleblue92
Newbie
Hello all, let me give you a rundown of the situation. I have recently had my mechanic to swap a motor from a 93 silverado into mine, as mine had a hole in the piston, floated valves, and blown head gasket. Anyways, ever since i got the engine back from him it has been running rough at idle. Cruising it seems to do fine. Well, really anything above 1500 rpm. When i go to crank it it cranks just fine but hesitates sometime and when it runs at first it is in 100-700 rpm range and wants do die. Once it finally catches itself itll have a pretty good lope to it like its got a cam. The motor i have in it is supposed to have a "RV" cam and it has an edelbrock torker II intake on it. It will idle like that until it goes into reverse or drive. When i shift it into either of those gears it will once again try to die and stay real low in rpms. It will have a lope to it (not all the time) on anything under 1500 rpms. But it does just fine at cruising. Once i let off the accelerator even if not to stop it will go real low in the rpm 2-500 and stay there until i either get back on the accelerator or it downshifts. Once i stop it will once again get real low in rpms and many times die. It has set up for quite a while before getting this other engine in it, which is supposed to have around 40-50k miles. Now another issue is today i saw soot, and small amounts of black smoke coming out at idle and maybe 5 mph but nothing beyond that. It had either water mixed with soot coming out hitting the ground or small amounts of oil coming out of the exhaust. Pretty sure it was water and soot but you could clearly see the small spots on the ground where the exhaust was spitting them out. I know before today i had a busted o2 sensor and i replaced it today and i think maybe i didnt tighten it enough but i plugged it in and went for a drive and it was the same. I know there was more than likely a bit of trash in the tank and i tried burning all of the old fuel. The fuel filter needs a change i know, im getting to that tomorrow. Its definitely running rich i can smell it, I have heard of the CTS causing these problems so i may change it but i dont have a clue where it is. Im not the most mechanic savy person but im trying to learn. I was thinking a ground could be loose or not on at all somewhere but thats why i am here to hopefully get some answers or suggestions on this problem. I have videos of it running i can post or you could see them on the GMT400 group on facebook. Please help, its much appreciated, Thank you!