Good morning gents. So 6 weeks in and I am still getting the ticking from the right bank and I have P 0171/4 codes. I have a set of new lifters that I am going to replace the right bank this week. HunterD, I read another post where you walked a guy thru fuel trims. I checked my live data using a scanner and found my long term fuel trims were both at 12.5, and did not change from cold to warm engine, or with throttle input. I have a Mitsubishi Tech letter that states that 12.5 is the magic number for these codes. Your thoughts? Did I forget to connect someone? Do I have a specific sensor or switch that is failed?

 

Long term fuel trim of +12.5 is a little high, but not "crazy" high. The CEL will get triggered if LTFT will go over 25%. What are your Short term fuel trims? Those will respond to throttle position faster and might be a better indicator of the vacuum leak. If you're able, post STFT for both banks.

 

Here is the data for the P0174

 

Fuel trims live data

 

Trying to upload pictures, and im not being successful. OK, here's the data:
Freeze data for P0174
Both fuel systems CLOSED
Calc Load: 16.9
Coolant: 185
ST FTRM1 25
LT FTRM!1 12.5
ST FTRM 2: 25
LT FTRM2: 25
Live at Idle:
ST FTRM11: 0.0
ST FTRM12: 0.0
ST FTRM21: 0.0
ST FTRM22: 0.0
ST FTRM1: 0.0
ST FTRM2: 0.0

At 2500RPM Stable for 1 minute:
ST FTRM11: -5.5 O2S11: 0.040 LTFTRM1: 12.5
ST FTRM12: 5.5 O2S12: 0.040 LTFTRM2: 12.5
ST FTRM21: 5.5 O2S21 0.180
ST FTRM22: 5.5 O2S22: 0.80
ST FTRM1: 5.5
ST FTRM2: 5.5

Both fuel sys loops OPEN and CEL OFF

 

Ok, Looks like you had a vacuum leak somewhere that triggered the CEL. Your Short Term trims were 25% on the freeze frame data. If you've done any work since, you may have accidentally fixed something like a loose air intake hose, or a vacuum hose.

I'm a little suspicious of your STFT showing all 0.0 at idle. It is possible to get STFT and LTFT to be zeros but rare. I wonder if that is the indicator of system running in OPEN Loop mode. Unfortunately OPEN Loop system means the computer is not using the O2 sensor feedback to adjust fuel/air ratio. This occurs in two situations - 1. During warm up, 2. As as Backup operating mode when sensor data is out of whack.

Take another reading and make sure the system goes into CLOSED LOOP. You don't need to "stabilize" engine RPM for long time to get good reading. Run engine at idle, note STFT and LTFT, then rev up. You want to open throttle fast and wide (for a short time) and record new fuel trim numbers. The reason for this is to reduce vacuum in the intake manifold to near nothing. Take note of how the Short Term fuel trims change from idle to open throttle. If they are High at Idle and drop to Zero or Negative number as soon as you hit the gas (and return quickly to positive once you are back at idle) - you still have a vacuum leak.

 

Ok so the system will only go into CLOSED if I get RPMs above 3000. Above 3000rpm, the LTFTRM1 goes to 9.3 and 2 goes to 6.4. the short terms jump all over the place. From -5.5 to 9.7. Once I get above 3000 and sit there. All ST go to -5.5 and only change if a get above 3500. Once I decel, the return to -5.5.

 

Would a clogged EGR valve/system cause this problem without throwing the P0400 code?

 

The rebuilt engine continues to chug along without issue other than the rough idle due to cylinder 6 misfire.....

Engine now has about 10.5k on it since the rebuild. Some very minor oil leaks - upper pan gasket and lower pan gasket so I tightened the bolts, shall see if this helps. Tightened the belt for the AC compressor as it would squeal occasionally. My other daughter is now driving the vehicle so the usage will increase.

Changed the oil this weekend (1000 miles overdue!) but level was good albeit a little blacker than desired. Magnetic oil drain plug had similar fuzz on it as it did at an earlier oil change.

Radiator is the plastic style with the metal top tank crimped on it. Noticed some coolant seepage at the seam. This is the 3rd radiator (4th counting the original) that have all developed leaks at this crimped seam. Used vise grips to tighten the crimps that were accessible. Anyone recommend a good brand of radiator that will not fail at this joint?

Oil with 8440 miles and 10,394 on engine

Oil with 1476 miles and 1875 on engine

Radiator coolant seepage at crimped seam

 

About to pull my hair out.
Since last post, I R&R'd the upper plenum, and, BEHOLD!!, the P0171/74 went away! Great news. Replaced coolant temp sensor connector due to broken wires, and replaced PCV valve. NO CODES!!! and running so smooth and strong... until yesterday. My son calls me and says that it died on him. i restarted once, then died again for good. Camshaft and Crankshaft codes. Got the covers off and it had jumped time. Screw it! I replace with ANOTHER new belt and new concentric pulley. Tensoined it so the pin would slip out of the NEW hydraulic tensioner. Got everything put back together, and it's running terribly. The kicker is that it is throwing no codes.
Full disclosure here. While pulling things apart, I was lazy and did not disconnect the battery. When I pulled the alternator, it slipped out of my hands and did some welding on the motor mount. To the point that the 100A fuseable link for the alternator fried. Replaced that, and everything works, except that it runs so bad. Seeing as I am throwing no codes, I was afraid that I might have fried the PCM, however, I am getting full live data. The only anomaly I can see in live data is that the #1 fuel bank shows OPEN, and the ST fuel trim seems out of whack. (I had fuel injectors on hand, so I replaced them precautionary). So to confirm the OBD was operating, I pulled the connector to the 3/6 coil pack. It shut down, and I got the P0300 random misfire. So I am confident that, at least from a I/M standpoint, that the PCM is good. I removed and inspected the PCM. There are no burn marks or evidence of shorts.
I am at a loss. I am going to pull the plenum this week and do a full compression check so HOPEFULLY rule out bent valves. I just can't figure out how it is running so rough without setting any codes. Has anyone seen this? Any words of wisdom would be appreciated.