Thermostat replacement - 2001 Monty Ltd
 

Where is the thermostat located on the 2001 Montero Ltd?

And...any tips on replacing it?

Thanks,

gc

Here is a pdf from the FSM for that procedure.

http://www.pajero4x4.ru/piii/GR00007600-14.pdf

Hope it helps.

Thank you, MR Z!

Its the bottom hose... Also becareful if you have a v6, that the thermostat should be about 6.3 cm's long. They gave me the wrong one at AutoZone...their computers seem to be messed up.

Thermostat issue
 

Hi guys, my Monti is starting to give me a check engine light. I have an INNOVA 3100 ABS sensor that tells me, when connected to the vehicle, that I have several codes pop. P0125, P0156, P0173.... and of course being who I am, and not reading anything first, I went and replaced the #2 O2 sensor on bank 2... hell of a job, but got it done.

But, resetting the computer, and then running the vehicle a few miles, as soon as it started to climb a hill at about 50 mph, the light came back on. So, I did a test run with the diagnostic tool connected while driving, says it's the P0156 again, and then the other two come on after I put her through the wringer to get codes to pop.

The computer online link says that it's possible that the thermostat is in a locked open state, causing the engine to not heat up enough in bank 2. Now, based upon all the charts I have, and the manual (tech manual) for the vehicle, bank two is on the left hand side of the vehicle here in the States... just making sure right?

Anybody else ever had this issue? What did you do to solve it?

The temp outside is about 75 degrees, sunny, and clear, humidity around 50 percent. The incline (hill) I was going up was a paved interstate of maybe 200 feet climb over a 1 mile distance.... not too much, but enough to add extra torque on the engine.

I did just have the plugs and wires changed, along with a distributor for a #5 misfire, so since I was going to do that, I just had them all replaced. Note, this error had been coming up for several months, but after the #5 came up as well, I took it in to a mechanic to do the work to change the plugs, I didn't have the time to do it myself.

My Monti is a 2001 LTD, about 164500 miles.

I do not believe the P0156 is in any way related to the thermostat. Engine has to be warmed up to operating temperature before PCM will start checking O2 sensor readings. Its probably just a secondary code. P0173 is directly related to engine temp (and possible result of the P0125 code). If PCM "thinks" that the engine is cold, it would be dumping more fuel into the cylinders, thus causing rich condition.
Item #1 to check is the engine coolant sensor. Check to see if it is plugged in, or if it is bad. It's possible that it was disconnected when the plugs and wires were done. Keep in mind - engine coolant sensor is a separate circuit from the one that shows on the temp gauge on the instrument cluster. As a result you may see the "normal" engine temperature on the gauges, but PCM is getting a different reading.

thanks
 

could you direct me to where the engine coolant sensor should be plugged?

they did a sloppy job on the plugs (my fault).... a few cables were loose... even vacuum hoses were loose. But it still feels like I missed something, on doing my QA of their job.

Check out http://www.pajero4x4.ru/piii/ Scroll down until you find chapter 13Ac and there go to page 13Ac-95, that has the workflow and diagrams for dealing with the P0125 (coolant sensor issues). You may want to bookmark this page, you'll be coming here often if you want to do your own work.