Posting mostly because I am bored, and the forum looks slow. It's snowing again so there's not much else to do today. I thought I would toss this out there after spending a couple days searching and reading. I have a plan of attack, but want to see what the consensus says.
Two weeks ago i had my battery disconnected for a three weeks. I had a few Spring things to do;
1) Fixing oil leaks (all the usual suspects; sensor o-rings, upper and lower oil pan, oil pump cover, and front crank seal)
2) Replaced idler bearings, rebuilt AC compressor, installed an electric fan with a On/Off/Auto (switched by pressure)
3) replaced water pump and re-oiled fan clutch
4) Rebuilt front diff with a Harrop, installed RCVs and Aisin freewheel hubs.
5) Removed VC and installed Marlin Gears in a known good lower mileage tcase.
6) New motor and trans mount.
Anyway, I now have a high idle.
A) 750-850 in gear no AC, slightly rough
B) 850 with a slight stumble when the AC comes on, idle is rough.
C) 1100 in neutral no AC, smooth idle
D) 1500 with AC on, slightly rough.
E) O2 voltages look normal on Torque app
F) O2 readiness has not completed
G) No MIL codes, pending, active, or saved
H) I've driven several FSM Readiness Cycles, along with my normal commute to work over the last two weeks.
I) Idle Air Control Valve clicks after shutting the motor off.
J) Timing was set to ~7* a couple years ago, I run 87 year round at 6000 feet.
K) EGR system is bypassed with a resistor in the temp sensor, due to a failed, relocated Dorman VSV. Been like this over a year.
When it warms up and quits snowing again my plan is to:
1) Check all wiring that I touched during all that work. Check for lose connections, crushed wires, and chassis grounds.
2) Return EGR to normal operation.
3) Return timing to normal.
4) Complete on vehicle diagnostics of O2, IAC, and TPS.
5) Clean throttle body, and replace any failed sensors if that's the problem.
6) replace spark plugs while I'm there
Some possibly relevant history;
A) full tune up was done 4 years ago and 30,000 miles, shortly after I got the truck.
B) 4 years ago compression was 160 across the board, except cylinder 4 was at 148.
C) replaced failed rear knock sensor last Summer
D) EGR was inop when I bought the truck, I replaced the dirty modulator, cleaned throttle body ports, and replaced failed EGR VSV with a relocated Dorman unit (which has since failed again).
If you're still reading let me know your thoughts. I appreciate the input and I'll try to document my troubleshooting... If it ever stops raining and snowing every weekend.
Two weeks ago i had my battery disconnected for a three weeks. I had a few Spring things to do;
1) Fixing oil leaks (all the usual suspects; sensor o-rings, upper and lower oil pan, oil pump cover, and front crank seal)
2) Replaced idler bearings, rebuilt AC compressor, installed an electric fan with a On/Off/Auto (switched by pressure)
3) replaced water pump and re-oiled fan clutch
4) Rebuilt front diff with a Harrop, installed RCVs and Aisin freewheel hubs.
5) Removed VC and installed Marlin Gears in a known good lower mileage tcase.
6) New motor and trans mount.
Anyway, I now have a high idle.
A) 750-850 in gear no AC, slightly rough
B) 850 with a slight stumble when the AC comes on, idle is rough.
C) 1100 in neutral no AC, smooth idle
D) 1500 with AC on, slightly rough.
E) O2 voltages look normal on Torque app
F) O2 readiness has not completed
G) No MIL codes, pending, active, or saved
H) I've driven several FSM Readiness Cycles, along with my normal commute to work over the last two weeks.
I) Idle Air Control Valve clicks after shutting the motor off.
J) Timing was set to ~7* a couple years ago, I run 87 year round at 6000 feet.
K) EGR system is bypassed with a resistor in the temp sensor, due to a failed, relocated Dorman VSV. Been like this over a year.
When it warms up and quits snowing again my plan is to:
1) Check all wiring that I touched during all that work. Check for lose connections, crushed wires, and chassis grounds.
2) Return EGR to normal operation.
3) Return timing to normal.
4) Complete on vehicle diagnostics of O2, IAC, and TPS.
5) Clean throttle body, and replace any failed sensors if that's the problem.
6) replace spark plugs while I'm there
Some possibly relevant history;
A) full tune up was done 4 years ago and 30,000 miles, shortly after I got the truck.
B) 4 years ago compression was 160 across the board, except cylinder 4 was at 148.
C) replaced failed rear knock sensor last Summer
D) EGR was inop when I bought the truck, I replaced the dirty modulator, cleaned throttle body ports, and replaced failed EGR VSV with a relocated Dorman unit (which has since failed again).
If you're still reading let me know your thoughts. I appreciate the input and I'll try to document my troubleshooting... If it ever stops raining and snowing every weekend.
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