Re: I need help! 1989 2.9 v6
Psychopete is right, there is a lot going on here. Lets go back to the engine with high mileage as an example. I might get a bit of this out of context, the "timing is right on", but there is another point to bring up. As you know the distributor is driven off of the camshaft and you can have the timing "right on" but the timing chain, even though it has those spring loaded guides supposedly taking up any stretched slack, some of these problems could because of a loss of synchronization of the spark timing and valve operations. So much was covered here, it hard to come up with anything, but this can be checked for. FIRST, remove the ground wire from the battery, then using a 1/2" drive ratchet and the correct socket, on the nut at the front of the crank holding the damper in place, and turn the engine in reverse with the distributor cap off, so you can see if the rotor starts turning right away or if there is a lot of lag. I have done this with V8s, so it can be done. Engine fans with fan belts turn clockwise when you are standing in front of the vehicles. (Serpentine belt driven fans could be reversed.) So, you want to turn the crankshaft counter clockwise while watching the distributor rotor. This is a judgement thing gained by experience. Another thing that you could do is to remove the water pump and visually check the chain and the gears. 2.9L V6s have a chain and the 2.8L has a gearset like inline sixes. If this is something you might want to try, don't forget to remove the ground from the battery and make sure you have the ignition off. This timing chain problem was a big problem witht he nylon covered timing gears that GM and Ford used in a lot of engines. Ignition timeing and valve timing have to work together, so maybe this is something that applies to some of these engines in this post. I am sure you can find the allowed play specification for the chain in the 2.9L in a manual somewhere. I put a waterpump in my 2.9L at about 80k and I saw a bit of play developing, I'll need to check it again someday. When you replace a stretched out chain in an engine, it is really a noticeable repair. Hope this "book" helps the thinking.
When I wrote the reply about the timeing chain, this post didn't look like this. I hope I didn't get it out of place and that its found by someone it can help. The other blog was long, I guess it did need modified.