Sudden Code P0068 and stalling, then all seems well

mitsubishi
mirage

#1

My 2015 Mitsubishi Mirage had a strange little incident the other day. I have posted this on the forum for these cars and as far as the people on that site know, I am the first to experience this exact issue. I also called the Mitsubishi dealer and they said this would be under warranty if it happened again. They said they had never experienced an issue like this in the Mirage either. Whatever this is isn’t a common problem which is good and bad.

I was pulling out into traffic and then there was a sudden momentary loss of power and then power returned. The check engine and traction control light were on. I pulled into another parking lot and when I came out, the check engine light was on but the traction light was off. I put the car in reverse to backup and it stalled. There was an Autozone across the street so I took it over there and had the code read. The P0068 appears to be a mismatch in input from the MAF, MAP, or TPS sensors.

I was low on gas but not that low so I went across the street to a gas station. While the car was filling up opened the hood and unplugged/replugged any wiring connectors going to sensors around the intake and manifold, wondering if it was a bad connection. The car took about 7.5 gallon of gas. These hold like 9.2 gallons or something.

I got in and started the car and there was no more check engine light. I hadn’t cleared the code so that wasn’t why. Anyway, I have been driving the car like normal the past 3 days with no repeats of the behavior.

I figure that a connector might have been loose from the factory or after the repairs from when I hit a deer a few months back. The car sustained front end and side damage so maybe something wasn’t plugged in snug enough after the work.

I guess I could have had a bad tank of gas and was starting to suck moisture or something. I would have thought that would have triggered a misfire or something so my guess leans to a loose connection. The CEL went away immediately when I started the car. The new tank of gas would have at least taken several seconds to have any impact.

Any ideas?


#2

What does “mismatch in input” refer to exactly? Does it mean the ECM is getting contradictory information form the various sensors it reads? One is saying one thing, another saying something opposite? Like if the TPS says the throttle is opening rapidly, the computer would expect the manifold vacuum to be reducing (less vacuum) , not going to higher levels of vacuum?


#3

From the internet:

P0068 MITSUBISHI - Manifold Absolute Pressure/Mass Air Flow Sensor - Throttle Position Correlation.

The Powertrain Control Module (PCM) monitors operation rationality check by comparing sensed throttle position to mass air flow readings

Possible causes - Faulty Mass Air Flow (MAF) sensor - Large vacuum leak - Leaking air duct system - Mass Air Flow (MAF) poor electrical connection - Manifold Absolute Pressure (MAP) poor electrical connection - Faulty Manifold Absolute Pressure (MAP) sensor - TP sensor not seated properly - Faulty Throttle Position (TP) sensor


#4

Use your warranty. Take it in to the dealer and have them check it. That way, if it becomes a recurring problem you’ll have begun to create a paper trail to support a claim. Be sure to keep your copies of all shop orders, a good practice anyway.


#5

I plan to do nothing and take it to the dealer if it happens again. My gut told me this was a poor electrical connection from the start and this appears to be one of the suggestions from Mitsubishi.


#6

I have put about 500 miles on the car since this occurrence with no further problems. I suspect that it was a loose electrical connection as the check engine light went off right after I unplugged and replugged the electrical connections. That being said, I will take it in for warranty service if it happens again.