cavi bucking, need help

not sure if related but I had ignition module and crankshaft sensor replaced, then one week later the car started bucking in 5th gear until all the way to 1st. Car would not start so replaced the EGR valve and put a new fuel filter -car fired right up. new set of plugs they were fuel-fowled-out, then replaced the ECM still doing the same thing and now when I pull up a code it says.... lean exhaust. Have had the car put on diagnostics and they cant figure out what is wrong. PLEASE help!!!!!!!! :banghead:

Sorry, need engine and tranny details. Does it turn over but not start?

engine is 2.2L, manual, The car starts and everything, but when you try to drive it bucks like crazy, you cant even get up to five miles an hour. I was thinking the problem might be in the fuel somewhere just not sure. :banghead:

You may want to try a new set of plug wires. I have two Cavi's and have been through this on both of them. Will the engine rev smoothly when out of gear? Also check for a vacuum leak. That will cause lean exhaust and missing. Low fuel pressure and clogged injectors also could cause what you describe.

Check ECM ground(s) and power supply connections to coils/ignition module.

Bad or intermittent connections will cause exactly what you describe-sounds ignition related to me.
The connection may LOOK good, but is it really?
Wait for the condition to happen and wiggle the connectors at the coil/module and at the ECM ground point and see if it changes things. If it does-clean and tighten the grounds and check the plug(s) at the coil/module for continuity while bending the wires a bit where they enter the connector and examine the contacs in the connectors closely for buggered up contacts/corrosion.

if it gradually got worse, there is probably a leak somewhere from the throttle body to the head. the extra air sucked in will flow in increasing your idle until the engine tried to compensate back to normal then the air comes in again and keeps repeating the cycle. check your aic valve (make sure there is a rubber o-ring on it, check the throttle body to manifold gasket/bolts, check the manifold to head. since the extra air is sucking into the engine it will have too much air causing your "exhaust system too lean" code. hope this helps