How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Doug Your Own Question
Doug, ASE Certified Technician
Category: Mitsubishi
Satisfied Customers: 6945
Experience:  Mitsubishi employed and Factory trained ASE certified technician
Type Your Mitsubishi Question Here...
Doug is online now
A new question is answered every 9 seconds

Mitsubishi Montero Sport LTD AWD: Doug, I have a Mitsubishi

Customer Question

Hello Doug,
I have a Mitsubishi Montero Sport 2003 Limited AWD/4WD with 182K miles. BTW I have the Factory Service Manual set for 2002. This has been a great vehicle and the first real breakdown. I was going uphill and the engine died, Found the Fuse link #2 open. The fuse link was replaced and instantly blew. In both cases the starter always cranked. We are a combination of Electronics Technicians and Mechanics in my X-Ray shop. We measured for a short to ground (ohms) on the load side of (F2 REMOVED) fuse link contact in three states, no key, key in run, key in start no obvious short circuit. We pulled the ECU (Passenger RT Foot side) and the Fuel Injector relay out, then opened up the ECU and smelled for electronic burn to no avail. We ohmed to ground all major semiconductors to see if there was an obvious short circuit to no avail. We put it back together and reattached the battery, the Montero Sport started right up, let it run, tested windows, door locks, sunroof, and ran it through the gears without moving the vehicle. The vehicle seemed to run fine. Today we decided to test drive it and went up the same hill and it died again, popped the hood and F2 was open. (I felt a jerk, not sure if the trans was shifting at that time then died) On another note, we measured the DC Milliamps at the shop during troubleshooting to be about 1/3 Amp in normal operation in idle. Is it possible that the issue is transmission related or throttle control since the manual page 90-15 shows F2 to supply Invecs-II 4 A/T, MFI and Immobilizer. Any Ideas? I hope its not a transmission.
Pat(###) ###-####
Submitted: 2 years ago.
Category: Mitsubishi
Expert:  Doug replied 2 years ago.
Hi Pat,
This can be a real bugger of a problem to diagnose, as the fusible link #2 powers the majority of the drive train controls... it is the MFI primary feed. I am most suspicious of MFI components here, as the immobilizer portions powered by this link are not likely to be problematic.
The transmission related portions using the fusible link 2 are shared with the MFI and an actual transmission related issue is extremely unlikely. The reference to INVECS for that link is specifically due to it reading the crank positions sensor...which is fed by the MFI relay, and again we are back to MFI components being primary suspects.
Did anything noteworthy change in the month or so leading up to this condition forming? Any recent repairs or maintenance of any kind?
Can you inspect your cam and crank sensor wires and make sure they are not near the belts or pinched slightly at the upper plenum brace where the connectors mount?
Also can you inspect the O2 sensor wiring, both the upper connector locations (They also get pinched sometimes where they mount on the plenum) and the lower sensors as well for wiring touching the exhaust etc?
Customer: replied 2 years ago.
Hi Doug,
I appreciate your quick response.We will check out your recommendations. As far as recent events go.... I have noticed an intermittent clacking sound under the Left Front side (Drivers). I purchased this vehicle with 71K miles and during diferent start ups it had a clacking sound. My Brother had Diesel Mechanic training and had his stethoscope handy at the 71K miles and convinced me that it was noisy injectors. Recently, the clacking has been intermittent and loud on start. I tested the vehicle by shutting the engine off and turning it back on. It didn't make sense to me that this sound could be an oil circulation problem especially after an immediate restart. That's the only peculiar behavior. Thanks,
Expert:  Doug replied 2 years ago.
Hi Pat,
The clacking sound is likely either injectors or collapsed lash adjusters (like lifters), both are extremely common on this model. With it being loud on start, it is probably lash adjusters.
Lets check those items I mentioned... the act of going uphill being a recurring cause of the fuse popping has me thinking there might be something loose moving around grounding out. If we can consistently create the issue going uphill, there is potentially some gravity playing a role in the short.
If you need a day or two to make those inspections that is no problem, I am here daily.
Customer: replied 2 years ago.
Expert:  Doug replied 2 years ago.
You're welcome.