Limp mode after replacing head gasket.

[Rezarafiq]

Hi guys,

I'm new to this forum and was wondering if anyone could help me out. I see members helping one another and looks like a friendly bunch.

Anyways, 2006 Chevy aveo automatic 1.6 cc engine.

I replaced the head gasket on it as water was sipping through and coming out of the exhaust. While the head was off I also managed to clean out a lot of gunk around the engine bay with a pressure washer.

I've got the head back on and timing is perfect but everytime I try starting the car, it goes into limp mode. It most of the time idles high about 2k and after awhile it goes down around 1.5k rpm. But it won't let me rev the engine past 2k rpm.

I have tried using an obd2 test and the it picked out:

P0107-Powertrain
Manifold Absolute Pressure/Barometric
Pressure Circuit Low Input

P0118-Powertrain
Engine Coolant Temperature Circuit High
Input

P0122-Powertrain
Throttle/Pedal Position Sensor/Switch A
Circuit Low Input

I'm quite clueless as to why it's doing that. There is an electrical plug which I have no idea where to plugs into. It's a circular plug with 3 pins in it. The plug is in the same wires which separates from the plug that goes into the air box. Around that area of plugs I've got other plugs connected already to the airbox, power steering line, throttle body.

Besides that plug everything else looks complete.

Can I have an opinion on this issue please?

[avguy]

Sounds like maybe some water got to where it shouldn't be. You might start diagnosing by checking voltages, first at the battery, both static and also loaded. If everything seems ok there, then check the sensor references, starting with the MAP wires.

[Rezarafiq]

Thanks for the reply. That's a good idea. I'll check the. Voltages and also will spray some crc into the contacts.

I will update if I have any luck tmr. Cheers