toadfist
Newbie
I'm stumped again... Well I guess more specifically I'm hoping I missed something before I drop the fuel tank to check the filter sock...
I have a 1996 Chevy C1500 with a 6.5 turbo diesel and 4L80e trans. Mileage is 140k, assuming it wasn't rolled back.
Mods work done, it's been running fine on this for a year or 2:
-EGR delete (freeze-plug and no-EGR-canadian manifold swap)
-Vacuum pump delete
-Turbomaster spring wastegate
-Aftermarket air intake box
-PMD relocate on fuel pump
-New fuel lifter pump (3 years ago)(no relay kit, though)
-Cheep boost gauge
-Braided steel transmission hoses and oil cooler lines.
-Big-3 Wiring wit 2AWG welding cable
-Triple redundant ground with 4AWG welding cable
-STOCK TUNE/no tune
This is what I've done over the past month. I'm not sure if this is related...
-Transmission
Transmission stopped shifting. I replaced all the solenoids in the transmission, the bubble switch, and the wiring harness. Truck drove again (and I think with normal power). I was hard shifting at this point, I was not sure if this was normal. I did not drive it much at this point, it was very hot, and the AC was broken.
-Air Conditioning
I drove the truck strait to an AC specialist and now she bows cold. Woo.
I thought the truck drove great at this time, but I did not drive it too much. My friend noticed it was not getting up to 80mph anymore, and it doesn't downshift. He thought it was a transmission problem, but I think it's fuel... You put the petal to the floor and it just slowly increases speed, doesn't down shift, cannot speed up going up a hill. Cruise control kicks itself out, and the truck will rapidly deaccelerate. Gauge says 8 lbs boost while it is doing this.
Problem seems to be slightly intermittent it seems to have normal power for like the first 5 minutes.
No stalls or close to stalls. AC on or off has no impact.
Replacements after unexplained power loss
Codes before changing sensors: P0236, P1653, P1870
MAP Sensor and pigtail
IAT and pigtail
Fuel filter
Cranked boost, hardly any change
Reset codes, now all 3 came back. P0236, P1653, P1870
After I post this, I'm going to replace input and output transmission speed sensors, but that's just hopefully to fix hard shifting. I expect the power issue will still be present. I also am going to quadruple check the air box, but I don't see how that would matter, it's making 8lb boost (maybe 10, crappy gauge holds -2 psi pre start). I should point out I was running a lower boost, and it had the same problem. I don't think it's over boost.
From what I've read, it could be the filter sock on the tank pickup? Most everything I've read that usually stalls though?
I have an ODBLink MX+ and torque pro... I can find the data for the IAT. But I can't find MAP Sensor pressure?
Any ideas before I drop the fuel tank on a hail Mary? Ad a fuel pressure gauge first?
I have a 1996 Chevy C1500 with a 6.5 turbo diesel and 4L80e trans. Mileage is 140k, assuming it wasn't rolled back.
Mods work done, it's been running fine on this for a year or 2:
-EGR delete (freeze-plug and no-EGR-canadian manifold swap)
-Vacuum pump delete
-Turbomaster spring wastegate
-Aftermarket air intake box
-PMD relocate on fuel pump
-New fuel lifter pump (3 years ago)(no relay kit, though)
-Cheep boost gauge
-Braided steel transmission hoses and oil cooler lines.
-Big-3 Wiring wit 2AWG welding cable
-Triple redundant ground with 4AWG welding cable
-STOCK TUNE/no tune
This is what I've done over the past month. I'm not sure if this is related...
-Transmission
Transmission stopped shifting. I replaced all the solenoids in the transmission, the bubble switch, and the wiring harness. Truck drove again (and I think with normal power). I was hard shifting at this point, I was not sure if this was normal. I did not drive it much at this point, it was very hot, and the AC was broken.
-Air Conditioning
I drove the truck strait to an AC specialist and now she bows cold. Woo.
I thought the truck drove great at this time, but I did not drive it too much. My friend noticed it was not getting up to 80mph anymore, and it doesn't downshift. He thought it was a transmission problem, but I think it's fuel... You put the petal to the floor and it just slowly increases speed, doesn't down shift, cannot speed up going up a hill. Cruise control kicks itself out, and the truck will rapidly deaccelerate. Gauge says 8 lbs boost while it is doing this.
Problem seems to be slightly intermittent it seems to have normal power for like the first 5 minutes.
No stalls or close to stalls. AC on or off has no impact.
Replacements after unexplained power loss
Codes before changing sensors: P0236, P1653, P1870
MAP Sensor and pigtail
IAT and pigtail
Fuel filter
Cranked boost, hardly any change
Reset codes, now all 3 came back. P0236, P1653, P1870
After I post this, I'm going to replace input and output transmission speed sensors, but that's just hopefully to fix hard shifting. I expect the power issue will still be present. I also am going to quadruple check the air box, but I don't see how that would matter, it's making 8lb boost (maybe 10, crappy gauge holds -2 psi pre start). I should point out I was running a lower boost, and it had the same problem. I don't think it's over boost.
From what I've read, it could be the filter sock on the tank pickup? Most everything I've read that usually stalls though?
I have an ODBLink MX+ and torque pro... I can find the data for the IAT. But I can't find MAP Sensor pressure?
Any ideas before I drop the fuel tank on a hail Mary? Ad a fuel pressure gauge first?
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