Wrong conclusion on the misfires. Three things are needed for a cylinder to produce power; fuel, air, and compression. The one that causes the least problems by far is compression. Just because it was good means nothing as far as misfires are concerned.
Chrysler has the least trouble with injectors among all manufacturers so look at them last. Most misfires are caused by ignition problems, (spark plugs and coils). That would be typical of the shaking you mentioned.
Low power can also result from a plugged catalytic converter in the exhaust system, although that will make the engine run uncommonly smoothly at low speeds. You'll also hear more of a hiss from the tail pipe instead of the normal "putt-putt".
Low fuel pressure can cause running problems, but the typical things that happen usually result in stalling while coasting, not while accelerating. I'd suggest borrowing a pressure gauge but the readings don't mean much because they change according to engine load. If there's no fault codes, the best plan of attack is to connect a scanner to see what the sensors are reading. Otherwise you're guessing and that's the least effective and most expensive way to diagnose it.
Friday, July 15th, 2011 AT 2:55 AM