Q: Car not running after throttle body with IAC valve replacement

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I have a 94 Mazda 626, 2.0, manual. I recently bought a throttle body with IAC valve (used). I took it all apart and cleaned it all with new gaskets. I've cleaned the EGR valve and modulator, the charcoal canister blew out all vacuum lines. Put new fuel filter, distributor cap and rotor, plug wires and plugs, blew out vacuum lines and new o2 sensor. Vacuum lines seems to be put back correctly and I've burped the radiator. After 1 hour of running the car the o2 sensor was covered with black soot already. Problem is, when starting the car I have to pump the gas pedal kinda fast for like a good 10 seconds while trying to start it before it wants to start once started it will idle but not driveable. I set timing by ear for now but I did adjust the idle screw and it is 3 turns out. When it's running there is a strong smell of fumes out the tail pipe. I can unplug the electrical connection on right side of throttle body and it dies and the the same with the TPS on the other side. Please help

Hi, thanks for writing in. I would recommend retracing your steps. You are definitely on the right track. It sounds like you did a good amount of work to your car, and it is likely that something may been skipped over or installed incorrectly. This often happens when numerous repairs are done in sequence. I would also check your fuel system because like you may be running rich. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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