Venture engine issues ?

I just bought a venture (2001) with 60k on it.
But when I drive the car on a highway I do feel some shaking through de bottom of the car. The steering wheel shakes a little.
When I start the car in the morning it feels like it runs on 5 cylinders. Just for about a minute. After that it is all fine. So I was thinking maybe the problem of the shaking on the highway is an engine problem. Can it be a misfire or should the check engine light come up in that case.

Since the engine sits transversely over the front drive shafts, any shaking should not be transferred into the steering wheel although its hard to guess what you are feeling.
http://cemrweb.cemr.wvu.edu/~mathews/venture/trans/engine+frame.jpg
Also, if the engine missed as badly as you describe at startup, you should see the SES light come on. Can you get someone to read the OBD2 codes that may be stored in your ECM? Misfire codes can be stored there without lighting the SES light, but if it happens every time you start the car it seems that the light should be on.

If you feel shaking in the steering while driving down the highway, I'd start at the tires. If nothing else, you can rotate your tires so the rear tires go to the front positions and check to see what effect that has on your shaking. I'd guess the misfire and the steering are not related.

Mine was shaking at idle (felt like a miss), I replaced plugs and wires, ran like a dream for 2 days, back to doing the same thing now. My fuel trims are pretty negative and my ignition advance is pretty retarded. IDK if my PCM is toast or I have something dumping excess fuel. I might try to replace my O2 first just to see if it is "READING" too rich and leaning the mix out enough to cause a near missfire feel.

lesterl, you might want to measure your fuel pressure, but on the question for this thread, I don't think any sort of engine miss or problem can cause shaking that's felt in the steering wheel while driving down the highway.

Fuel pressure was fine last time I checked.... But am curious to see if OP has used any fuel system cleaner or something of the sort?

do you feel the vibration while you are under acceleration? if so check your cv axles for wear and play in the joints.