Why Does My 1989 Dodge D100 Have Rough Idle And Smoke
Posted in Ignition Systems | Asked on Aug 11, 2010
The truck is a 3.9 L V6 with 3 spd auto transmission. The engine has been rebuilt in the garage, fitted with new bearings, gaskets, lifters and piston rings. The distributor has been adjusted as best as possible. When the truck is started the engine runs rough and vibrations can be felt in the steering wheel. The engine rocks side to side rather noticably in the compartment. Is this normal for a Dodge pickup? Once the rpms increase, the truck runs smoother. While it runs, quite a bit of grey smoke comes out the exhaust pipe. It smells like burning oil, but where can such a problem be coming from? Finally, my engine makes a sort of ticking or clicking sound. Sort of like a kah tick kah tick that seems to fade at higher rpms. Is this unusual? Thanks
There are 3 Answers
They screwed up your timing. It’s probably off a tooth or 2 and is making your valves stay open a little longer than they should in retrospect to where the piston is in the cylinder.
Also your new rings need to break in to the cylinders and may be letting oil by them. That will take time to see if they break in and the smoking stops.
Unless they didn’t stagger the ring gaps when the put the rings in.
It could be a number of things making it run rough, but I would be worried about that smoke that smells liks oil!
It sounds to me like something is messed up in the engine: it could be a valve that wasn’t done quite right or “stacked” rings like the other guy says.
The valve problem could make a tap and smoke.
I have a recording of valvetrain noise on my website, in my noise library:
http://econofix.com/noiselib.html
One note: most mechanics send their heads out to a machine shop to get them done: it may not be the guy who did the rebuild who missed something.
It could also be a defective hydraulic lifter: that will make one cylinder weak.
Do a compression test, better still a leakdown test.
Check the manifold vacuum at idle.
You need go back to garage that did the rebuild, there is no excuse for bad work. Don’t let them sell you a story about breaking in the rings, that is baloney. The distributor has been adjusted to best possible ?? What does that mean ?? If the distributor will not turn far enough to set the proper timing then that means the valve timing is out of time. The timing chain was not installed correctly. Make them fix it. No excuses.