1990 Buick Lesabre

I recently rebuilt the engine (3800) in my Lesabre but it is very hard to start and won't idle when it does start. When I do manage to get it to run for a few minutes, only while holding down the gas pedal, I can see smoke coming out from under what appears to be the front or front-right side of the engine. There does not appear to be any oil leak but I did notice that there is something that looks like soot on the lower radiator hose. Any advice of what I'm overlooking that could be causing this would be appreciated. I put brand new valves in the rebuild so I don't think it is that but I'm clueless at this point. Also brand new plugs a few weeks ago and the old ones where carboned up pretty bad. Thanks!

P.S. I'm generally pretty good on the Buicks but this one has me stumped.

I would start old school and check Fuel pressure and spark. Then
Because even though you done something a million times. Always check your work. Make sure your cam trimming is correct by pulling the cam sensor and looking to see if the magnet lines up at #1 TDC. That being OK, its time to start a compression test. If they are around 200psi across the board, its time to buy a scanner and start looking for the bad sensor/wire that did not like getting removed and replaced. It sucks trouble shooting a problem on an engine that has never run. This makes the OBD useless. No scanner you say. That is OK, just use a DVOM and an Oscope.

TNTTL. Thank you very much for your advice but, unfortunately , all of those things check out ok. I am just going to maybe have to tow it to the dealership and see what they say.

TNTTL. Thank you very much for your advice but, unfortunately , all of those things check out ok. I am just going to maybe have to tow it to the dealership and see what they say.

Dealership? Oh no. With a vehicle that's almost 20 years old I would be taking it to an independent garage. Surely you can get recommendations from friends and family. There's a reason why dealerships are referred to as "stealerships" on this site :lol:

Dealership? Oh no. With a vehicle that's almost 20 years old I would be taking it to an independent garage. Surely you can get recommendations from friends and family. There's a reason why dealerships are referred to as "stealerships" on this site :lol:

It won't be going to a dealership. I mostly said that out of frustration. I'll figure it out if I have to take it all back apart. Thanks to all for their suggestions though! It is just kinda discouraging that I rebuilt the engine and have all these problems (my first rebuild). The engine was fine so I should have just left it alone. I was taking automotive classes at a local community college and needed to rebuild one so figured I'd do my own. I'll think twice before rebuilding a perfectly good engine next time.
I also have a battery drain that I never had before. Rebuilt the steering column (Unlike the engine, It WAS screwed up, thanks to a car thief) so I'm thinking I have a dead short in the turn signal actuator since the right turn signal does not work but hazards and everything else, including bulbs do. Getting it running right is my first priority though. Then I'll tackle the short.

This reminds me of when I timed the injection pump on a IH diesel tractor 180 degrees off. I could get it to run, but not very well. I had timed the pump to the intake stroke, #1 cylinder, TDC, but needed the exhaust stroke, #1 cyl, TDC. I knew this might happen when I put it back together, so I rotated the engine around one more time. Once re-timed on the next go-around, it ran great. Sounds like the timing is not an issue on your Lesabre though.

Maybe there is a bad or disconnected ground somehwhere?

You know what is funny. I was just thinking last night "I wonder if it is 180 degrees out of time?" I am out of town until monday night though so going to check that next Tuesday. Only a few hour job anyway so won't hurt.

Conceptually, I suppose you could swap your plug wires for the paired cylinders at the coil packs-just to see if it runs any better. Seems like that would put the spark in time if you are 180 out. Probably wouldn't help your fuel delivery though. Not sure about that. The injectors would probably be out of time (still). Someone else would probably know more about this than I do.