got the car scanned today, codes pulled were P0300 (multiple random misfires) and P0171 (system too lean)

Handing the keys over to my mechanic friend who will be going through the diagnostics tomorrow...

Also made him aware of the injector o-ring TSB #0613009

 

i told you it was stupid lean!

was it knocking at all?

 

I haven't noticed any knocking/pinging but to be honest I've been home sick the last couple of days haha so if I have been driving I've been way too out of it to pay it's due attention.

We had it running in the shop today while hooked up to the diagnostic scanner and didn't observe any knocking or pinging, by that I mean that neither were audible and the scanner read normal ignition timing - ie. no fluctuations or changes - even though the car was noticeably idling rough... which I find odd. It was the O2 sensors that were reading a little funny though. They weren't in sync, seemed to go on, off, both, sync up, alternate, repeat. Was strange. Could a bad O2 sensor cause this kind of grief?

I've also been thinking about how those other spark plugs ended up in my car and my theory is: an overzealous mechanic had maybe swapped them out to see if a longer gapped, hotter spark would solve the lean condition and may have forgotten (or purposefully left) those plugs in. As to why that would happen without my knowing is beyond me.

 

i get a P0420 from the highflow cat, but it doesn't change my AFR...but that just means the O2 sensors are still working and the catalytic converter is not, lol...try replacing one, and then the other...

 

Results from today's tests basically show that the MAF is reading a lower volume of air than it should be, but still in an acceptable range.

At idle the car should be taking in 2.0 - 6.0 g/sec, mine reads 2.5.

At 2500 RPM the car should be taking in 8.0 - 16.0 g/sec, mine read 8.2

^ So that's sitting on the low end of things.

Did an ether test for vacuum leaks, found none.

No exhaust leaks found.

Air intake and engine coolants temps are normal and verified functioning...

Barometric pressure test is reading at a 95.5 kPa (we're 577m above sea level, 600m is supposed to be 95 kPa)

Injector resistance should be 10.5 - 13.5 ohms, mine are a little on the high end with #1 at 13.1, #2 at 13.1 , #3 at 13.2, and #4 is at 13.2

We've ruled out contaminated fuel as well.

A variety of other test show everything else is otherwise normal, aside from the previous o2 sensors reading funny, these appear to be operating normal...

 

Swapped the throttle body back to stock and changed out the plugs (lol "special order" spark plugs...) to no avail, still lean.

Also considering trading out intakes and going back to the short ram, After some searching I guess some people had problems in the past with a misfire code, lean code, or both after installing their RRM CAI?

The MAF readings are making me wonder if the intake can be attributed to at least one of the problems that are occurring - possible, but not likely.

 

i would pull the piggy at this point...

 

if he's running the piggy has he tried restting his ECU? i've never had any problems like these with running lean even with all the mods im running on my car.

i would try pulling the CAI first and where that leaves you cause i've also heard of people having code issues when they swapped from SRI to CAI. also when was the last time you've gotten your MAF cleaned?

 

The MAF was cleaned when I first started noticing these problems, probably about a month or a month and a half ago.

I've reset the ECU about 4-5 times in the last month, each time when I fire the car up it idles high (but smoothly) for a short while - and then it starts bogging/idle seeking, not sure why it changes like that

I'm definitely swapping intakes tomorrow if I'm feeling up for it haha, just started feeling better today.


Definitely contemplating just pulling the piggyback, but if I remove the piggyback will the car run alright with the mods that I have?

 

well, you'll be running more rich so you'll likely see a drop in power....

 

I think I underestimate the strength of the computer in our mitsu's, hopefully it's nothing the ECU can't handle.

If it weren't raining/snowing today I'd be more enthusiastic about trading intakes, if the short ram doesn't improve anything then the piggyback is getting pulled...

 

Swapping the intakes out seems to have solved the problem(s).

Car can hit WOT without leaning out, purrs like a kitten and idles smooth and quiet - if it weren't for the solid motor mount I probably wouldn't feel it - and my exhaust odor has richened up a healthy amount with the short ram back on.

Probably for the better, CAI's aren't the best choice of intake around here.

That's lame.. never would have thought the CAI would have cause that much grief...

 

you sure it wasn't leaking?

 

We'd checked it for leaks when we did the ether test for intake/vacuum leaks, everything was tight and couldn't hear any air escaping everywhere, otherwise would have seen an immediate spike in the rpm's

I thought the short ram intake was loud a long while back, now that I have it installed again do I realize how loud the CAI actually is.. too bad that didn't work out

 

makes no sense...intake shouldn't make any difference what so ever...MAF placement is roughly the same...maybe the connection on the MAF was not making good contact...