TurboDennis
SILVER Star
Having some issues with my truck and was hoping somebody could point me in the right direction.
I had my injection pump and injectors rebuilt last summer by a local shop that has extensive experience with Bosch-style pumps and very good reputation.
The engine had 170k KM on it at the time, and there was absolutely nothing wrong with it - i just wanted to service the pump/injectors as preventative maintenance. Was running 1HD-FTE turbo, pushing about 13 PSI. Fuel pump was never touched before, and it ran great.
The guy that was rebuilding the pump said that with factory settings, the 1HD-FT pump would not be able to supply enough fuel for the increased boost that i was running, and it would need to be adjusted. That made sense to me, so I told him to go ahead and do what needs to be done. The guy said I should expect more power and better fuel economy.
I installed the new pump and injectors, and installed a roof top tent at the same time. After a long trip, i noticed that my fuel economy has decreased. Was getting about 10.5L/100KM (22.5MPG) before, and went down to about 12L/100km (19.5MPG). I attributed this to addition of RTT, and didn't pay much attention to it.
However after putting more miles on the truck since then, I'm convinced that the truck is over-fueled. I'm getting noticeable black smoke on startup, at low RPM (before boost), and during full throttle acceleration. EGT's usually climb to around 500-600C (950-1100F) during small hill climbs, but have gone as high as 800C (1450F) during long mountain passes in high gear (at which point i would downshift and back off the throttle). The weight of the truck is close to stock, running 33" tires. I didn't have an EGT gauge before the fuel system rebuild, but i believe these EGT's are way too high for 13 PSI and a relatively light truck.
I have never messed with IP, but i want to try and reduce the fueling a bit. What would be the best adjustment to make, and how much? I asked the guy that did my rebuild how much he adjusted the compensator spring/main screw relative to factory level, and his response was "I dont know. I don't count turns - i adjust by injection volume in CC's on a stand"
Second issue that I'm having, which may or may not be related: After the truck sits for at least a few hours, it starts great and holds the idle perfectly for as long as i let it idle before driving. However after driving it a few seconds (and letting the turbo kick in once), it wants to stall when dropping the RPM's back to idle. There is a stop sign 50 meters from my house, and it always wants to stall at that stop sign. I have to bump the RPM's with pedal to keep it from stalling. It only does this once, and the problem never reappears until the truck is parked again. However this happens VERY consistently, pretty much 100% of the time.
If anyone has any suggestions, I would really appreciate it!
I had my injection pump and injectors rebuilt last summer by a local shop that has extensive experience with Bosch-style pumps and very good reputation.
The engine had 170k KM on it at the time, and there was absolutely nothing wrong with it - i just wanted to service the pump/injectors as preventative maintenance. Was running 1HD-FTE turbo, pushing about 13 PSI. Fuel pump was never touched before, and it ran great.
The guy that was rebuilding the pump said that with factory settings, the 1HD-FT pump would not be able to supply enough fuel for the increased boost that i was running, and it would need to be adjusted. That made sense to me, so I told him to go ahead and do what needs to be done. The guy said I should expect more power and better fuel economy.
I installed the new pump and injectors, and installed a roof top tent at the same time. After a long trip, i noticed that my fuel economy has decreased. Was getting about 10.5L/100KM (22.5MPG) before, and went down to about 12L/100km (19.5MPG). I attributed this to addition of RTT, and didn't pay much attention to it.
However after putting more miles on the truck since then, I'm convinced that the truck is over-fueled. I'm getting noticeable black smoke on startup, at low RPM (before boost), and during full throttle acceleration. EGT's usually climb to around 500-600C (950-1100F) during small hill climbs, but have gone as high as 800C (1450F) during long mountain passes in high gear (at which point i would downshift and back off the throttle). The weight of the truck is close to stock, running 33" tires. I didn't have an EGT gauge before the fuel system rebuild, but i believe these EGT's are way too high for 13 PSI and a relatively light truck.
I have never messed with IP, but i want to try and reduce the fueling a bit. What would be the best adjustment to make, and how much? I asked the guy that did my rebuild how much he adjusted the compensator spring/main screw relative to factory level, and his response was "I dont know. I don't count turns - i adjust by injection volume in CC's on a stand"
Second issue that I'm having, which may or may not be related: After the truck sits for at least a few hours, it starts great and holds the idle perfectly for as long as i let it idle before driving. However after driving it a few seconds (and letting the turbo kick in once), it wants to stall when dropping the RPM's back to idle. There is a stop sign 50 meters from my house, and it always wants to stall at that stop sign. I have to bump the RPM's with pedal to keep it from stalling. It only does this once, and the problem never reappears until the truck is parked again. However this happens VERY consistently, pretty much 100% of the time.
If anyone has any suggestions, I would really appreciate it!
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