Low torque shudder

[ricky68]

So , a couple of weeks ago in the middle of a monsoon I was driving and when I shifted in to overdrive my tahoe started shuddering /lagging. I gave it a little gas and when I got my rpms up it went away til I got behind a car going up a steep incline when it started again. Got in it a few hours later and it was fine. Got up for work the next week and it done it a couple more days then it just quit.Shortly thereafter my check engine light came on and is still on. am getting an error code p0327 which is the knock sensor.I am also wondering if it is the knock sensor could this account for the poor mileage . I am getting about 11-13 mpg . This is a brand new crate motor with only about 10k or so miles on it.I should at least get 15 or so.

99 tahoe 5.7 I am posting this test log maybe it will help.Thanks for your help.


TID:$02 CID:$10
- Lean to Rich sensor threshold voltage(constant)
Min: 130
Test result value: 130
PASS
----
TID:$02 CID:$11
- Lean to Rich sensor threshold voltage(constant)
Min: 375
Test result value: 376
PASS
----
TID:$02 CID:$12
- Lean to Rich sensor threshold voltage(constant)
Test incomplete or dependant test failed
--
TID:$02 CID:$20
- Lean to Rich sensor threshold voltage(constant)
Max: 800
Test result value: 20
PASS
----
TID:$02 CID:$26
- Lean to Rich sensor threshold voltage(constant)
Max: 70
Test result value: 14
PASS
----
TID:$02 CID:$30
- Lean to Rich sensor threshold voltage(constant)
Test incomplete or dependant test failed
--
TID:$02 CID:$31
- Lean to Rich sensor threshold voltage(constant)
Max: 120
Test result value: 65,533
FAIL
----
TID:$02 CID:$40
- Lean to Rich sensor threshold voltage(constant)
Test incomplete or dependant test failed
--
TID:$02 CID:$46
- Lean to Rich sensor threshold voltage(constant)
Min: 100
Test result value: 100
PASS
----
TID:$06 CID:$35
- Lean to Rich sensor switch time(calculated)
Max: 75
Test result value: 41
PASS
----
TID:$06 CID:$41
- Lean to Rich sensor switch time(calculated)
Max: 158
Test result value: 156
PASS
----
TID:$06 CID:$55
- Lean to Rich sensor switch time(calculated)
Max: 75
Test result value: 48
PASS
----
TID:$06 CID:$61
- Lean to Rich sensor switch time(calculated)
Max: 170
Test result value: 130
PASS
----
TID:$07 CID:$0c
- Minimum sensor Voltage for test cycle(calculated)
Max: 0
Test result value: 56,320
FAIL
----
TID:$07 CID:$0d
- Minimum sensor Voltage for test cycle(calculated)
Max: 197
Test result value: 64,091
FAIL
----
TID:$0c CID:$20
- Misfire counts for last/current driving cycles(calculated)
Max: 112
Test result value: 62,373
FAIL
----
TID:$0c CID:$30
- Misfire counts for last/current driving cycles(calculated)
Max: 112
Test result value: 56,555
FAIL
----

 

[SunlitComet]

well not the data i was hoping for but it looks like the cylinders are misfiring. pull a misfire history report to find the suspected cylinders and re examine their ignition components. the code makes me think the sensor or wiring is goofed or not mounted properly. it is listening for engine and knocking noise and what it is hearing is not enough. that may mean that it may not be torqued properly so as not to even hear the engine.

 

[SunlitComet]

correct gas right?

 

[ricky68]

Correct gas? Does that mean I am supposed to be running non-ethanol only?Or a higher octane? Here is another set of data I foumd.

Fuel Status = 0 byte
Engine Load = 13.333 %
Engine Coolant Temperature = 89 °C
Fuel Trim Bank 1 Short Term = 0 %
Fuel Trim Bank 1 Long Term = 3.125 %
Fuel Trim Bank 2 Short Term = 1.562 %
Fuel Trim Bank 2 Long Term = 6.25 %
Intake Manifold Pressure = 5.366 psi
Engine RPM = 2,114 rpm
Speed (OBD) = 88 km/h
Mass Air Flow Rate = 30.24 g/s
Throttle Position(Manifold) = 7.451 %

 

[SunlitComet]

yeah was not sure besides the crate if anything else was changed like tunes since there was not much info as to why it was done. the pcm seems to be trying to correct a lean condition on the right bank. see if you cant fix the knock sensor code issue and perhaps take a read of the plugs to see if there are signs of fuel mixtures issues. also don't forget to check the misfire history i mentioned.

 

[ricky68]

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