Codes not adding up

abrad

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Going to compare those tomorrow when I have the chance. The first MAF I’ve already returned. Yes, I do have a live-data scanner. Compression and fuel pressure will be next
 

abrad

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So, did a little testing today - damn it’s hot outside!
New unit plugged in, won’t idle and keeps stalling.
revved it to about 3000 rpm -
Maf 16.4 g/s
O2 bank 1 -.005 // -.015 (negative numbers)
O2 bank 2 .051
Unplugged the unit, idles around 1100
Maf 0.0
O2 bank 1 .745
O2 bank 2 .125-.195

old unit idles about 1150
Maf 2.98 g/s
O2 bank 1 -.004//-.047 (negative numbers)
O2 bank 2 .165//.185

now, and this is totally new, I’m getting “pending codes” 300, 301, 302, 303, & 304. Random misfires, but the check engine is not on, these are just showing up as “pending”. There was also a code (bad me, I didn’t write it down) that showed O2 reading lean. When I went back in later, that had left the pending codes. Weird.
 

billr

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Also take a peek at MAT/IAT. And MAP, if it is displayed. Report what you find.

Are you sure about the MAF units? They seem roughly 5x to 10x what I calculate they should be. (I presume "g/s" means grams per second)

I would ignore the P03xx codes for now, those are to be expected if it is running poorly.
 

abrad

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I’ll double check all that this evening when I get home from work.
Thanks for the help
 

abrad

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What is TPS doing at idle?
TP is showing 0.0%
O2 is at negative .470– negative .520 mA
Shouldn’t those numbers range further? Also, shouldn’t they be bouncing around quickly? They are moving somewhat slowly on my monitor…
 

grcauto

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TP is showing 0.0%
O2 is at negative .470– negative .520 mA
Shouldn’t those numbers range further? Also, shouldn’t they be bouncing around quickly? They are moving somewhat slowly on my monitor…
The monitor has a slow rate. If you can graph it it should show it going from about .15 to .85 up and down about every couple seconds. Faster at cruise.
If it hangs high or low or has a slow switch rate it can cause problems.
 

billr

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Again, it is imperative that the OP verify what the readings and units are of the data being posted. In reply #17 no units were given, but I kind of figured they were volts, for NB sensors. Also, reply #17 mentioned a "bank 2", but there should not be a bank 2 with this I-4 engine. Was that, perhaps, supposed to be bank 1 sensor 2?

Then, in reply #22, O2 sensor readings were reported as current, and very low at that (<1 mA). Current readings aren't generally (ever?) displayed for WB sensors, and don't apply at all to NB. Does the "upstream" sensor, B1S1, have a 4-wire cable or a 5-wire cable? WB sensors are usually 5-wire.
 

grcauto

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Again, it is imperative that the OP verify what the readings and units are of the data being posted. In reply #17 no units were given, but I kind of figured they were volts, for NB sensors. Also, reply #17 mentioned a "bank 2", but there should not be a bank 2 with this I-4 engine. Was that, perhaps, supposed to be bank 1 sensor 2?

Then, in reply #22, O2 sensor readings were reported as current, and very low at that (<1 mA).
Current readings aren't generally (ever?) displayed for WB sensors, and don't apply at all to NB. Does the "upstream" sensor, B1S1, have a 4-wire cable or a 5-wire cable? WB sensors are usually 5-wire.
The signal from all sensors are voltage related and the only part of any sensor that is measured in amps is the heater circuit.
 

abrad

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The signal from all sensors are voltage related and the only part of any sensor that is measured in amps is the heater circuit.
Again, it is imperative that the OP verify what the readings and units are of the data being posted. In reply #17 no units were given, but I kind of figured they were volts, for NB sensors. Also, reply #17 mentioned a "bank 2", but there should not be a bank 2 with this I-4 engine. Was that, perhaps, supposed to be bank 1 sensor 2?

Then, in reply #22, O2 sensor readings were reported as current, and very low at that (<1 mA). Current readings aren't generally (ever?) displayed for WB sensors, and don't apply at all to NB. Does the "upstream" sensor, B1S1, have a 4-wire cable or a 5-wire cable? WB sensors are usually 5-wire.
Ok, yeah, I’ve been a bit brain fried the past few days between work and this!
Yes, I mis spoke when I said bank 2, it is bank 1, sensor 2
Just now started it back up, and ran the sensors again -
Bank 1, sensor 1 - all negative numbers, ranged mostly -0.629 to -0.574, with one drop to -1.02 mA
Bank 1, SENSOR 2 ranged from 0.0 to 0.015 V
IAT read 30°c
MAP read 38 gpa
MAF read 2.5 g/s
TPS read 8.2%

Thoughts? Any other info? I haven’t yet done compression tests or fuel pressure tests, those are probably this weekend, Saturday likely, as I’m taking my son and daughter striper fishing in Long Island sound Sunday before he goes to his first duty station a couple days later.
 

billr

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"gpa" for MAP???

MAP for an un-boosted (no turbo) engine will be in the 20-101 kPA (kilo Pascal) range. I don't know what "gpa" means, but it doesn't sound valid...

What rpm for those readings just posted? Was the throttle fully closed?

Those negative "mA" O2 sensor readings are really vexing. I think you have a NB sensor (count the pins, please!), and output from those should never go negative or involve current (mA) readings. I feel like we are wandering in the weeds now. What scanner (make/model) are you using? Post a screen-shot of some of these readings/units I am confused about.
 

grcauto

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2004. I don't think these had the wide band O2 sensors but maybe check that.
 

abrad

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"gpa" for MAP???

MAP for an un-boosted (no turbo) engine will be in the 20-101 kPA (kilo Pascal) range. I don't know what "gpa" means, but it doesn't sound valid...

What rpm for those readings just posted? Was the throttle fully closed?

Those negative "mA" O2 sensor readings are really vexing. I think you have a NB sensor (count the pins, please!), and output from those should never go negative or involve current (mA) readings. I feel like we are wandering in the weeds now. What scanner (make/model) are you using? Post a screen-shot of some of these readings/units I am confused about.

Scanner is an Autel link 619. I’ll get some screen shots tonite after work. I believe it is a 4 wire sensor, haven’t got under to look. I also will be checking the resistance on it once I get underneath.
 
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