I really need some help, I purchased this Montero and the previous owner disconnected the MAF because it would not run with it connected. I have changed the MAF, the boot because it was cracked and leaking, the IAC, cleaned the throttle body and changed the TPS. Starts up great but once it is warm there is no control of the throttle, moment you press the gas it dies out, unplug the MAF and it runs but is blowing black smoke. Any help or ideas are greatly appreciated

 

Have you checked the TPS for proper calibration? If you have a OBD scan tool(preferably bluetooth), you can calibrate it by watching the throttle position sensor data. it should ideally read zero when throttle is not pressed. If it's out of calibration, you can loosen the TPS bolts just enough to adjust it while watching the sensor data. This is how I've always done it. The fuel pressure regulator could be kaput. The regulator should be underneath the temp sending unit. You'll see a vac line running to a little cylinder right on the end of the fuel rail. If you have a vacuum gun you can put some vacuum on it and see if it holds. May not be getting enough fuel. (clogged fuel filter, faulty pump, etc.)

 

So I should add I had been driving it before I started the repairs, it would run even on the freeway just fine but at low speeds the idle would jump around. After changing the TPS it started great until it warmed up then it started stalling whenever I touched the gas pedal, unplug the new MAF and it runs. So the fuel regulator would be working fine, I will calibrate the TPS today but just adjusting to the marks I put on the old one got it started and I did move it slightly both directions and it would start blowing black smoke from tailpipe. What gives the MAF signals, would that be the O2 sensor. Thanks for your help

 

The MAF gives signals to the ECM about humidity, air temperature, and barometric pressure if I recall correctly. Nothing really talks to the MAF per say. That being said, the new MAF and(or) IAC could also be bad, a lot of aftermarket electronics for this model are pure garbage. I would highly recommend going to the nearest junk yard and pulling a MAF and an IAC from there to test with. Bad O2 sensors can also give bad data to the ECM and cause all sorts of odd issues but they shouldn't be causing a stall. I would definitely look into getting the IAC and MAF from a donor(check the donor has original parts). A clogged catalytic converter can also cause these symptoms if it's bad enough.

 

Would the throttle body cause this and can you suggest a scanner I can buy

 

So to follow up on my continuing issue, I rescanned and got the following codes: P0105, P0100, P0110. I found a throttle body but the MAF was already gone at the yard. Installed it and disconnected the battery cables, cleared all the codes and started, with it cold it idled perfectly till it came off high idle then it died again, undid the new Amazon MAF and it idles good. I am thinking like many have said the china MAF does not work well in our cars so unless someone has another suggestion I will start searching for an original. I appreciate all the help

 

Same issue here for months, stalling as soon its gets warm, no stalling if i disconnect the maf, no check engine light...
- New MAF sensor
- New coolant sensor

Anyone? please!