I have a 2000 Galant ES, 2.4L, 4 cylinder, 105,000 miles, which abruptly began to idle very roughly and blow heavy gray smoke upon starting. The vehicle will stall once in gear and I attempt to accelerate. By abrupt I mean one day it ran, the next it didn’t.

I’ve had the guys that routinely work on my vehicles and who are friends of mine, one who is Mitsubishi trained, attempt to diagnose the problem with no success. I’m not familiar with all the details, but they’ve done the following which I’ve noted according to their instructions…

· Scan vehicle using 3 different scanners to include a Mitsubishi Factory scanner;
· Back pressure check on converter;
· Compression check;
· Pressure tested coolant system;
· Fuel pressure test;
· Pulled top cover and timing marks ok;
· Cleaned mass airflow sensor.
· Disconnected the battery and later reconnect in attempt to re-set the computer.

All were ok and did not indicate a problem. They are of the opinion that it’s an electrical problem and the scans did not pick it up for some reason. The guys did call the nearest dealership and ran the problem by their service dept and everyone is still stumped.

My next and only option and my mechanics agree, is to tow it to the dealership, an hour away and let them make an attempt. This concerns me because of the cost and in the end, I still may not have a diagnosis or fix. As you know the vehicle isn’t worth but so much given the year and mileage; however, before this problem, was a good additional vehicle.

Any suggestions or speculation would be appreciated? Thanks.

 

Well I immediately thought of the timing belt. They can stretch, and partially break. Mine Idled terribly before it broke... The computer will work hard to make the timing work despite the stretched belt. Also, 2000 galants Idle terribly for half a week when you disconnect the negative terminal. If the battery connections are not strong, then this could cause the computer to cycle like it had been disconnected... Also check your fuses including your relays.

 

This vehicle was towed to the nearest Mitsubishi dealership where scans were made in mid-August. The initial scans and exam did not reveal a solution. The service mngr said it was as if someone had a heart attack but there were no identifiable cause. The dealership called Mitsubishi Tech people and a decision was made to drain the gas tank and replace the spark plugs and wires. The vehicle then ran fine; however, the dealership was unsure if the original problem was the gas or the spark plug and wires. It is noted that I had changed the spark plugs (but not the wires) in July 2008 approximately 9K miles before this problem occurred. The vehicle has been driven since the repair without any further problems.

 

I don't know what year/model Montero you have. If you search around on the forum, there are several threads here where people describe removal/installation of the intake manifolds on multiple models. As far as coils - primary coil is low voltage side where signal computer comes and secondary coil side is where spark plug wires connect. keep in mind - resistance values might differ based on your specific model. Read through the "Why don't you have the manual" sticky thread. There are links in there where you can find FSM for different years.