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2000 Avalon - Possible Transmission & Fuel/Air System Issues - Need Advice

Ok, here is what happens to my car:

  1. the engine wobbles when idling or at very low speed - some times the engine shuts down in stop and go traffic (very dangerous).
  2. doesn’t pick up speed when i try to accelerate from a stop position - the engine revs up and then the car lurches forward (suddenly) as the transmission seems to engage. The same happen when i slow down to almost very low speed and then tries to speed up. I also hear a kind of thud (transmission most probably)
  3. The CEL is ON and some time blinks.
  4. My OBD is showing the following codes: P0171 P0172 P1150 P0300 P0302 P0304 and P0306

I moved this car with me from the US to the Middel East when i took a job there; is still want to keep the car… the mechanics here are no good and i need to narrow down the possible causes and then prioritize to tell the mechanic what exactly to do. Your advice is highly appreciated and thanks in advance.

have the catalitic (however its spelled lol) checked

Yeah, you have some serious misfires.
A blinking MIL means the misfire is considered severe enough to damage the catalytic converter(s)
Perhaps it’s time for a tune-up . . .
How many miles?
Are the plugs and fuel filter up to date?

the car has 137K miles… the fuel filter has been changed; didnt help… i also smell (un-burnt) gas.

This symptom can be caused by at least a dozen differnent things. Bringing all the routine engine and xmission maintenance up to the owner’s manual schedule & spec couldn’t hurt. That’s the first thing I’d do if it were my car. It might well fix the problem. And if it doesn’t, well, it had to be done anyway, right?

My guess there is a fuel/air mixture problem of some sort involved, but it may be interplaying with other problems due to deferred maintenance.

In my opinion, you may have a lean condition (possibly a vacuum leak, possibly a leak in front of one of the oxygen sensors) which is causing the PCM powertrain control module to request additional fuel.

Inspect the air intake tube from the air cleaner to the throttle body. If it is cracked or has come loose the vehicle will set fuel system lean codes (P0171, P0172).