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Ping time. (Not carbon buildup)

That was a long breakfast LOL
 
Ecomike said:
That was a long breakfast LOL
Click to expand...
Yeah Windows updated and Sony Vegas shit the bed as a response. It keeps rendering audio and black screen. No video. Been trying to fix this all day. I'll link it here as soon as I can figure this mess out

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It could be a timing problem. It's pretty simple to check timing chain slack on these. That's a starting point but know that the ECM also plays a role in engine timing.
 
JeepJango said:
It could be a timing problem. It's pretty simple to check timing chain slack on these. That's a starting point but know that the ECM also plays a role in engine timing.
Click to expand...
I have detailed footage of the timing live feed on both a hot and cold engine and under load. If Sony Vegas is no longer compatible with Windows 10 as of the latest update then I'll just have to refilm it in one shot. Be up by Sunday

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My 01 does the same. I try to run 89 octane. It doesn't do it much on 89. It was good for a while after running an inch of different types of system cleaner. I've wanted to run some BG44k through it but I still ill haven't ordered it. I have also tried water through the intake.

When I originally researched it I read a few times that a vacuum leak may cause it. My brake booster does hiss a little sometimes but I don't have any other symptoms of a vacuum leak. I did pick up a borescope but have yet to put it into the cylinder to have a look.
 
My head is new, I just put it on and saw the cylinders are pretty clean. So unless some buildup in the intake is the issue then mine is definitely not carbon.
Got my editing software working and it's rendering as we speak. I'll have the video of my live feed and readiness check up by tonight

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The O2 data is all over the place, at 2500 rpm in park it should be a very tight band from .040 to .050, .045 average.

Not sure what to make of the limited data you captured on fuel trim, it is in %, and the FSM lists 128 as a number base line, and above or below that number is positive or negative trim, going from 0 to 255 I think (Using a snap on MT-2500 scanner). Not sure what OBD-II % means, but I do not it can give you awesome data on what the ECU is doing versus the what the ECU knows is normal!!! Read up on fuel trim, it can be an awesome tool along with O2 sensor data. That O2 sensor data is either way too slow to post or the system is wandering all over the place from very rich to very lean. At 2500 rpm it should be super tight range bound, at idle they tend to bounce all over the place.

alexgalexg said:
Here is the live feed. Cold under load, hot under load and readiness test. Also life feed before start up. Any feedback would be great.
https://youtu.be/KFeNmnPsiXM
Click to expand...
 
Last edited:
What rear end ratio and tire size ????
 
https://www.obd-codes.com/faq/fuel-trims.php

"Keep in mind that the computer has no idea if the o2 sensor is reading properly in some cases. For example if an o2 sensor was sticking rich, the computer would assume it was reading correctly and begin taking away fuel to compensate. This is referred to as a "false rich" condition. The computer would be leaning the engine and setting a possible P0172, P0175. The codes would indicate the engine was running rich but it ACTUALLY is running lean. If you use only the false rich codes to diagnose and don't observe all the fuel trim and o2 sensor data, you may make a false diagnosis."
 
Ecomike said:
The O2 data is all over the place, at 2500 rpm in park it should be a very tight band from .040 to .050, .045 average.

Not sure what to make of the limited data you captured on fuel trim, it is in %, and the FSM lists 128 as a number base line, and above or below that number is positive or negative trim, going from 0 to 255 I think (Using a snap on MT-2500 scanner). Not sure what OBD-II % means, but I do not it can give you awesome data on what the ECU is doing versus the what the ECU knows is normal!!! Read up on fuel trim, it can be an awesome tool along with O2 sensor data. That O2 sensor data is either way too slow to post or the system is wandering all over the place from very rich to very lean. At 2500 rpm it should be super tight range bound, at idle they tend to bounce all over the place.
Click to expand...
Yeah it's a limited reader. I don't have access to a better one. None of the under load data was in park. I was driving. Only time in park was off or idle

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Check the STFT and LTFT in park at several engine speeds. LTFT should not change much. Post up the highs and lows and RPMs
 
Ecomike said:
https://www.obd-codes.com/faq/fuel-trims.php

"Keep in mind that the computer has no idea if the o2 sensor is reading properly in some cases. For example if an o2 sensor was sticking rich, the computer would assume it was reading correctly and begin taking away fuel to compensate. This is referred to as a "false rich" condition. The computer would be leaning the engine and setting a possible P0172, P0175. The codes would indicate the engine was running rich but it ACTUALLY is running lean. If you use only the false rich codes to diagnose and don't observe all the fuel trim and o2 sensor data, you may make a false diagnosis."
Click to expand...
I haven't noticed any significant ghosting or wetness on the plugs. Tomorrow I'll pull 2 from this jeep as well as my other one and compare. But if they are reading incorrectly am I supposed to replace them? Or is this being caused by an alternate issue. Wired improperly, bad catalytic ect

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Ecomike said:
Check the STFT and LTFT in park at several engine speeds. LTFT should not change much. Post up the highs and lows and RPMs
Click to expand...
I misread and did the test at different speeds of travel, not rpm. I will have to try the rpm thing tomorrow

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Test in park
1,500 rpm
SHRTFT1: .8 - -3.9
LONGFT1: 3.9
2,000 rpm
SHRTFT1: -0.8 - 1.6
LONGFT1: 4.7
2,500rpm
SHRTFT1: 0 - 3.9
LONGFT1: 3.9 - 4.7 (only changed once)
Idle
SHRTFT1: -10.2 - 0
LONGFT1: 3.1 - 2.3
Hope these help

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https://www.google.com/search?q=positive+LTFT+OBD-II+why&ie=utf-8&oe=utf-8&client=firefox-b

The LTFT is above the new vehicle ECU/PCM baseline.

Could be OK, could be something.

LT is long term, an average of the ST Short term number over weeks....and months.

So on average: "Positive fuel trim percentages indicate that the powertrain control module (PCM) is attempting to richen the fuel mixture, to compensate for a perceived lean condition"

Check all the write ups on the links from that google search link for hints as to what your data means and what to do while driving and to watch for for additional clues. That was just one hint I quoted.

Also once you have various RPM, decel and acceleration (driving) data, wipe the PCM memory by disconnecting the battery to force it back to the new car baseline tables in the ECU and rerun the tests, and watch them over time as the LTFT accumulates a history and see what that indicates.

A new properly working rig should have a LTFT close to zero. The STFT will be all over the place (if everything is working) -10 to +10 (IIRC, maybe not that drastic, I forget, but (-) to (+) for sure) as you speed up and slow down, WOT to heavy breaking.
 
Ecomike said:
https://www.google.com/search?q=positive+LTFT+OBD-II+why&ie=utf-8&oe=utf-8&client=firefox-b

The LTFT is above the new vehicle ECU/PCM baseline.

Could be OK, could be something.

LT is long term, an average of the ST Short term number over weeks....and months.

So on average: "Positive fuel trim percentages indicate that the powertrain control module (PCM) is attempting to richen the fuel mixture, to compensate for a perceived lean condition"

Check all the write ups on the links from that google search link for hints as to what your data means and what to do while driving and to watch for for additional clues. That was just one hint I quoted.

Also once you have various RPM, decel and acceleration (driving) data, wipe the PCM memory by disconnecting the battery to force it back to the new car baseline tables in the ECU and rerun the tests, and watch them over time as the LTFT accumulates a history and see what that indicates.

A new properly working rig should have a LTFT close to zero. The STFT will be all over the place (if everything is working) -10 to +10 (IIRC, maybe not that drastic, I forget, but (-) to (+) for sure) as you speed up and slow down, WOT to heavy breaking.
Click to expand...
You mentioned something about my o2 data. My connector for my upstream (on the exhaust manifold) o2 broke. Not where the pins connect but the shroud around it. I am pretty sure I have it connected the proper way but it's possible I do not. Would it be possible that this is the issue? Or would it just stop working entirely if connected wrong

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