Vibration 1993 Chevy Van 10 - 4.3

Hello everyone, I have a vibration at idle and at various speeds. You can feel it in the wheel at times and you can see the mirrors move, as well as the dipstick and the antenna. The vibration gets better and worse at various speeds. I did a complete tune up including plugs, wires, cap, rotor, air filter, O2 sensor. I checked for vacuum leaks (none) and changed the trottle body gasket. There were no codes present. Checked the EGR valve function at the garage. (was ok) The vehicle failed the emisions test, but I changed the catalytic converter and the vehicle passed with flying colours. (in all categories) I took it to another garage and they told me it was a bad distributor. Before I go ahead and buy a good used distributor at the salvage yard, can anyone give some imput on this situation? I have spent a ton of money so far to make this annoying problem go away and no luck as of yet. Thanks in advance...Steve
BTW...the van has 80,000 miles on it (not Kilometers) US van

Does it do it in gear or out of gear?
What engine? Auto or std transmission.
Is the engine missing?

Remove dist cap and see if the rotor shaft has side play.
Them years was bad on dist shaft bushings.
MT

The Engine vibrates in gear and also out of gear. Out of gear its not too bad, but I can still feel it. While in gear, it gets worse at certain speeds and not so bad at others. I drove it from New Jersey to Ontario (8 hour drive) and it really tired me out :) It is a 4.3 litre engine with a 4L60 E automatic transmission. The engine is not missing. Tommorrow I will remove the cap and check for that side play. Thanks so much. BTW...I'm a true GM guy and have always used Delco parts :)
Regards Steve

If the engine is not missing check engine/transmission mounts.
Also crank pulley damper and flywheel and or clutch if a standard.
Good luck and let us know how it goes.
MT

I pulled the distributor cap and there was not any side play at all on the rotor shaft. Looks like I will have to take it to the garage to check the engine and tranny mounts, as well as the crank pulley damper. I am not very confident in the mechanics in this area. :(

Good luck and let us know how it goes.
Tips on finding a good repair shop and tech/mechanic.
Check around Ask around
Word of mouth.
Family friends coworkers neighbors business people and delivery people.
Mailmen and parcel delivery people get around and notice a lot of stuff.
Even a good parts house knows what shops are good and not good.
Chamber of commerce and better business bureau and city hall.
If you find a good referral to a repair shop go look them over and talk to them.
Look for a clean looking busy place with nice people running it.
Ask a few questions and ask about their qualifications and training.
Not all places have trained tech/mechanics.
If they do not find a place that does.
Even all dealers do not have all trained techs/mechanics.
MT

I took my van over to a garage that came highly recommended . I explained to them the history of the vehicle (as far as I knew, and what was discussed above) although I only bought the van last September. They checked the motor mounts, transmission mount, and the crank pulley damper. They told me that everything was good and tight. They did say that it looks the transmission had been recently rebuild because it was clean and had a sticker attached to it belonging to the rebuild company. The only thing the mechanic could suggest was that maybe the torque converter was out of balance. Any suggestions or comments would be greatly welcome. Regards Steve

Start it up and speed the engine up slow to about 3K rpm and tell us at what rpm speed it vibrates at.
And if at any speed does it vibrates more than other?

I don't have an RPM gauge in the vehicle, and I have to hold off on spending a lot more money on this van. But I can tell you that it pretty much vibrates at all speeds. I spoke with some transmission specialists and asked them if they thought it may be the torque converter. They told me to check the flywheel for trueness and unbolt the converter from the flywheel and slide it back toward the rear of the vehicle. Then start the van and see if the vibration continues. This should give me some indication. :banghead: :banghead: :banghead:
I can't wait to post a smiley face when this issue is resolved.

Yes that would be a good test on the transmission converter but will not test the flywheel or front engine crank damper.
Has any work or changing or repair been done on it when th viberation started?

The van had this problem when I purchased it last year. Like I mentioned above, it looks like a relatively new transmission, but I have no repair history on this vehicle. The front engine crank damper was checked and I was told it's ok. Another thing I should mention, when I start the vehicle, the starter seems to crank the flywheel super fast. I takes only a split second to start the vehicle. Not sure if that is relevant or not.

Make sure the transmission is bolted up to engine good.
Then try the unbolt the transmission convertor.
If that does not help you may have a cracked flywheel or the wrong one.
Some years and applacations the flywheel has engine balance weights on the flywheel.
You need to match the flywheel to what year the engine actually is not just what year the vechicel is. Sometimes years of engines get changed.
Good luck
MT