live data dump. what do YOU see?

[commercialfshrmn]

at idle, the trim cell stays at 37, but under load (2k rpm+) it clears right up and stays normal.

New parts this week: MAF, Plugs, Wires, Coils, EVAP under the hood, EVAP canister in the rear, all o2 sensors (i can only change 3 of them, because when they stole my cats they cut it off to the point where i can't get to it to do anything with it)

i dunno if people say it enough, but thanks to all of you who take the time out of your day to help people with these things. i'm a fisherman, but learning to be a mechanic it seems lol. seriously, freaking thank y'all.

codes:

live data:

https://imgur.com/sJPInN4

going to switch 6 and 8 around (coil packs & wire) to try and rule out hardware. again, at 2k rpm everything clears up perfectly.

 

[Doubeleive]

ambient air 104? are you in the desert

 

[commercialfshrmn]

ambient air 104? are you in the desert

no. in the swamps of eastern nc (inner banks)

 

[SpareParts]

MAS air flow needs to be changed to grams for me to read it.
What is your AAT and IAT cold after sitting overnight.

 

[commercialfshrmn]

MAS air flow needs to be changed to grams for me to read it.
What is your AAT and IAT cold after sitting overnight.

roger. will have him change it tomorrow when we do it again.

i'm honestly not sure what they would be. what should they be?

 

[SpareParts]

IAT and Ambient should be very close to the same when cold after sitting overnight before you start it.
MAS should read around your engine size in grams a second when hot up to temp and idling between 550 and 600 rpm

Both front O2 sensors new? The rears have no effect on how it runs. The rears are only there to make sure your cats are working.
Check fuses under the hood for heated O2 sensors. I think there are 2. I don't know what the default is if blown but it looks like either the sensors are not getting power to the sensors or non heated sensors were installed.

 

[Fless]

Do us a favor and post properly-oriented pics. Ditto on Mass Air Flow reading in g/sec - much more accurate than the imperial scale.

What was the issue before the parts were replaced?

And now, besides the obvious mis-fire on cyl 8, what's the specific complaint?

 

[strutaeng]

Lean on idle that improves (especially if only one bank) points to a vacuum leak.

I didn't see all the data, some of it had glare. Just post the values at the rpm.

 

[Fless]

I didn't see rpm in any of those pics, although my neck hurts and I may have missed it. None of the pics show that the PCM has fuel control (it's in open loop) so the O2 sensor readings aren't really going to indicate anything worthwhile.

Seeing the codes for the O2 sensor heaters, do the heater circuits have good fuses in them, and is the voltage making it to the sensors?

 

[commercialfshrmn]

IAT and Ambient should be very close to the same when cold after sitting overnight before you start it.
MAS should read around your engine size in grams a second when hot up to temp and idling between 550 and 600 rpm

Both front O2 sensors new? The rears have no effect on how it runs. The rears are only there to make sure your cats are working.
Check fuses under the hood for heated O2 sensors. I think there are 2. I don't know what the default is if blown but it looks like either the sensors are not getting power to the sensors or non heated sensors were installed.

gotcha. it idles between 550-600 every time.

yep, oem o2 sensors. i'll definitely look at the fuses.

Do us a favor and post properly-oriented pics. Ditto on Mass Air Flow reading in g/sec - much more accurate than the imperial scale.

What was the issue before the parts were replaced?

And now, besides the obvious mis-fire on cyl 8, what's the specific complaint?

just running misfiring/bad mpg/shuddering going down the road SOMETIMES.
now it's doing the same shit. granted, i'm gone half of the year offshore & the only time i have to really mess with/fix anything is during the winter.....so that kid of sucks - i'm going to re-post the pics underneath of this comment that are straight

Lean on idle that improves (especially if only one bank) points to a vacuum leak.

I didn't see all the data, some of it had glare. Just post the values at the rpm.

refresh this in 5 mins and the pics wil be straightened out (underneath of this comment)

 

[commercialfshrmn]

I didn't see rpm in any of those pics, although my neck hurts and I may have missed it. None of the pics show that the PCM has fuel control (it's in open loop) so the O2 sensor readings aren't really going to indicate anything worthwhile.

Seeing the codes for the O2 sensor heaters, do the heater circuits have good fuses in them, and is the voltage making it to the sensors?

gonna go check the fuses in a minute. at idle, fuel trim cell is 37. above 2k and driving it's normal.

 

[commercialfshrmn]

it's running like a bad MAP would, from everything i've read about them going bad. and you can smell fuel.

 

[SpareParts]

MAP says 4.06 PSI. I would like to see that at least 18 PSI or higher. Maybe im thinking in/hg

 

[commercialfshrmn]

MAP says 4.06 PSI. I would like to see that at least 18 PSI or higher. Maybe im thinking in/hg

i'm going to get one tomorrow, worst comes to worst i take it back. i just changed the 02 sensor fuses, started it, no check CEL. runs like shit, but no light. everything i've read/watched about a bad map is exactly how it runs

psi to hg says that it equals out to 8.266

 

[Doubeleive]

a bad map sensor and the ambient sensor reading funky could be causing "some" of the problems, mainly air-fuel mixture.
I would inspect the ambient sensor make sure it is mounted where it should be on the radiator support frame.
I believe it can be ohm tested but if in question maybe grab one from a junkyard, they tend to get brittle and the clip on it breaks
if you disconnect the battery and then go drive it 55 for 3-5 miles the ambient sensor will self-calibrate and start reading correctly (if it is working properly).
I don't think it would cause a misfire count on a single cylinder though, swap coil packs and see if the problem follows the coil or not.

 

[commercialfshrmn]

also, wtf does this connector go into? right by the front headlight. seen it swinging around. smh

 

[SpareParts]

Lean on idle that improves (especially if only one bank) points to a vacuum leak.

I didn't see all the data, some of it had glare. Just post the values at the rpm.

I'm also leaning to a vacuum leak but got to rule out possibilities.

 

[Fless]

also, wtf does this connector go into? right by the front headlight. seen it swinging around. smh
View attachment 489217

It can likely reach only so far. Move it around and see if there is something disconnected.

Also, which headlight? "Front" gives us a 50/50 chance when guessing. DS? PS?

 

[Fless]

What did I miss that indicates a lean condition, other than the MAF value?

The MAF reading in the pics is 0.04 lb/min, which equates to 0.3 g/sec (but, again, reading it directly in the metric standard would be most accurate). That's severely low; at hot idle (we don't know what the idle was) it should be close to the engine displacement in liters. That would indicate an inaccurate or dirty MAF, and the intake air temp issue would also indicate a problem with that particular combination sensor.

 

[commercialfshrmn]

It can likely reach only so far. Move it around and see if there is something disconnected.

Also, which headlight? "Front" gives us a 50/50 chance when guessing. DS? PS?

after doing some research, it's gotta be unplugged from the ******* pcm? WTF!?! that's the literal only place it'll reach. if you're looking under the hood, right below the light. there's 2 holes that i could FEEL it would only go in, and then it got dark.

What did I miss that indicates a lean condition, other than the MAF value?

The MAF reading in the pics is 0.04 lb/min, which equates to 0.3 g/sec (but, again, reading it directly in the metric standard would be most accurate). That's severely low; at hot idle (we don't know what the idle was) it should be close to the engine displacement in liters. That would indicate an inaccurate or dirty MAF, and the intake air temp issue would also indicate a problem with that particular combination sensor.

that MAF sensor is brand new, x2. brought the first one back, tried this.

running lean, or rich? because all you can smell is fuel

also w/ the temp, the truck had ran for a literal minute until i cut it off again. drove from my house to 1/5 mile down the road.