2003 Montero sputters and dies

Offroadmuch

Explorer
Hello All,

My idle is very rough and getting worse. Will barely run, spuuters and dies. Disconnected the wire to the MAF sensor and it runs perfectly. Service guy at the dealer says it is the throttle body assembly. What do you guys think?
 

coffeegoat

Adventurer
Someone mentioned on the FB group the other day to use a chassis code (or engine code) on Aliexpress or similar to find parts that are more challenging to find in the US. My part number find for the throttle body ended looking different (perhaps different assembly) but I did find it on both OEMMitsubishi parts for 900, and on aliexpress for 188. I'd try cleaning it first, but apparently you can sometimes find parts on aliexpress.
 

Salonika

Monterror Pilot
Take it off, take it apart, clean it, put new seals in it.... but unless it was damaged somehow I don’t see that as being a component that would ever need replacement.
 

Offroadmuch

Explorer
Report from the dealer:
It is throwing 30 codes, many inter-related. Cracked exhaust manifolds on both sides, “needs a new intake manifold” possibly EGR valve, O2 sensor and mass air flow sensor.

I suspect it is hard to tell since some of these parts effect downstream performance and sensors but that is what they said. About $5000.00 dealer cost. I don’t have the tools or time to do the work myself.

There is a very good chance I will sell it. Runs perfect when the MAF is unplugged. Only one year on my Kumho AT-51 tires including spare, spacer lift on all 4 corners. Has the third row seat and tow hitch...
 

Michael Brown

Adventurer
Throttle body was discontinued as a new part. Used ones can be found in junkyards and eBay to test with a different unit.
https://www.ebay.com/p/2003-Mitsubishi-Montero-3-8-V6-Throttle-Body-MN137646/1825020686

30+ codes seems strange, and if it runs without the MAF, then it has to be fairly simple. I expect most of the codes are due to running with the MAF unplugged from earlier. I would get a list of the codes yourself. I taught my dad how to use this code reader so he can self diagnose and clear trivial ones(outside air is colder than expected) on his old trucks.
Buy this ELM327 reader from eBay in your choice of wifi or bluetooth connection. (FYI this reader works with almost any vehicle made since 1997 due to the global OBD-II standard)
Install the app for your phone or tablet.
Connect to the reader and run the app to get the codes.
Write ALL of them down on paper before clearing them.
Clear the codes with the ignition on, engine off.
Turn the key to OFF and let it sit a few minutes.
Restart the engine (with MAF plugged in)
Re-read the codes and write down the ones that have returned.
Post all the codes that were originally there and ones that returned after clearing.
We should be able to give you the causes for them and figure out exactly which parts are bad.
 

Offroadmuch

Explorer
Mine:
 

Offroadmuch

Explorer
$2500.00
 
I was having similar idle problems, 3 unplugged cats and a new driver side manifold seems to have gone and cure the problem for the mean time. I cleaned out the TB before all that and it helped for a while, but the problem came back couple weeks afterwards.
 

Offroadmuch

Explorer
$1000
 
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