Mitsubishi Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter #1
My engine light came on and was told that the codes are a172, 173, and a 131. those codes of horse are a rich and lean and a O2 sensor.

however the symptoms are is that it feels like a hard miss. when it idles it idles smooth as a kitten. Sometimes it runs perfect for a day other times when I get up to speed you can feel the miss. and other times there is a small surge if I keep my foot steady as though the TPS sensor is going bad.

I put some seafoam in it the other day and that seemed to help a lot. But there's still a feel of a rough running at 30 - 35 miles an hour. One of the technicians that came out to look at it was unable to get his computer to link up with the ECM.

so before I fork out lot of cash, does anybody have any other ideas what this might be.

Acceleration is really good. I have no problem getting up to speed. Two major times I feel it is usually around 30 miles an hour. And usally within the first 20 or 30 minutes of driving I can feel it on the highway stuttering.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #3
OK new plug and coils...
now runs REALLY rough.

no power

OLD plugs were junk, burned and some at 80-90 gap!!!!

there were two issues. bank2 had a bad hold down bolt almost came out with the nut. fought that. and was able to secure the coil back inplace.
bank 1 cylinder 1 nut and top part of bolt snapped. so coil fairly locked in place.

the rest of the coils tight.

truck runs like ALL the plugs are bad.

So going to check to see if the coils are seated in tight. anything else to check for? do those hold down bolts come out? i cold not get BANK 2 and cylinder 2 to come out, just spins in place after about an inch and a half.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #4
NM, got distracted with me and a buddy while we were swapping plugs, apparently one of the coils got put back on WITH NO SPARK PLUG - OK, so fixed that, runs smooth, there is a very small miss. Mostly seems to happen when letting up on the accelerator. Kinda like a "skip". So we are going to put a TPS in, given the condition of the mounting bolts on the plugs, we feel nothing has been done to this truck since it was released.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #5
Done.
I ended up purchacing a throttle body, as these have the IAC and TPS as part of the unit. Truck is running fine now. Final issues:

Old plugs (some were gaped over .090!! and all were corroded), changing these made a vast different.
TPS seemed to solve the low idle, and intermittent stalling and stuttering.
 

·
Registered
Joined
·
1 Posts
This sounds very similar to what happened to my 2003 galant. Symptoms: occasionally got very hard bucking at 60 mph, died when accelerating from stops, rough idle, and many other things. Long story short, it was the coil packs and mainly the mass air flow sensor. Replacing only one of these didn’t solve the issue completely. If you decide to get a new MAF I highly recommend oem, took a risk on something cheap and it didn’t pay off. Hated my car for the longest time but now that it’s fixed I’ve never had so much fun, and also became a diy mechanic from all the research
 
1 - 6 of 6 Posts
Top