PO300 code, car undriveable, need advice

[super97gst]

I have been dealing with this problem now for a little over 2 months. We have had a thread going on this same thing as well for a while, but i still can't figure out what has gone wrong on my gst. It also hasn't been driveably since this all happened. 2 months ago when all this started i was sitting in the car with it idling. I was messing around with the BC and as soon as i put the car in reverse and started backing up the bottom fell out of it. It's kind of hard to explain the symptoms. The car now idles at 100 rpm's or less, but it will stay running, it will not die while idling or any other time. The engine also shakes horribly bad, like i've got 1 or 2 dead cylinders. After this happened i just shut the car back off. The next day i went back out and cranked it up and it was just fine. I drove it for 3 days with no problems at all. Then i was about 15 miles from home and cruising down the road and it started again. I barely made it back home. The car took forever to get to 60 mph. It will only rev up to about 3k, and it's really slow about getting to that. Also the boost will only go up to 5-6 psi.

I ran a diagnostic check on the car and it threw a PO300B code. It also gave me a PO141B and a P1104 code. The 141 code says 02 sensor bank 1 - S2- Htr. malfunction. I assumed this was from eliminating the cat with my downpipe. The 1104 is a manufacturer controlled fuel/air metering. I looked that one up though and it said turbocharger wastegate solenoid malfunction. I dont know if that could cause the PO300 or not. Also, the scanner said this too. Fuel system Status - Bank 1 - OPDC, Bank 2 - Disabled. I dont know if that has anything to do with this problem either.

These are the things i have done so far, and these were all brand new oem mitsubishi parts. CAS, ignition coil pack, NGK BPR6ES plugs, NGK plug wires, coolant temp. sensor and i was told an alternator could cause this so i put a new alternator on as well. I have also tested the IAC motor and TPS, both were good. I just pulled the battery out of the car to make sure i hadn't broken any wires or ground anything accidentally, couldn't find anything. What do i do next guys, i really need this car back going. 2 months is a long time to just have the thing sitting here doing nothing. I'm open to any and all suggestions if it will just get it fixed. thanks a lot.

Blake

 

[keithscianna]

Any updates?

 

[bboyalan]

Hey guys,

Any small/big updates on your side? Just yesterday I received a P1400 for the MDP sensor on top of the intake manifold. Ironically, it works in conjuction with the EGR which we were discussing before. I went ahead and cleaned out some of the gunk and will see if it or the EGR needs more cleaning/replacement.

 

[Artago]

Hey guys,

Any small/big updates on your side? Just yesterday I received a P1400 for the MDP sensor on top of the intake manifold. Ironically, it works in conjuction with the EGR which we were discussing before. I went ahead and cleaned out some of the gunk and will see if it or the EGR needs more cleaning/replacement.

I replaced my MDP, P1400 went away but P0300 persisted. Recently I cleaned the hell out of my EGR and installed a new gasket. Haven't road tested it yet because my turbo is out for warranty work. Will update when I get my turbo back.

Tom