I have been chasing a high start idle for some time now and I was using the o ring trick for a while until I thought more about it. I did all the checks prescribed in the FSM and could find nothing wrong.
I removed the throttle body and it was filthy. I also noticed that a port was completely blocked that goes to the EGR modulator.
The top view of the body.
Port "R" was plugged with garbage at this end.
Port "R" was also blocked in here. I used my welding tip cleaner set and lots of compressed air and TB cleaner to clean these ports. These holes are hard to see as they are ~ 0.030" and inside the body.
This is the EGR modulator that "E" and "R" go to.
The truck now starts fine and goes to 1200 for about a half second then drops to 800 when cold then ~650 when warm.
I don't know exactly what cured it because I did many things at once:
1. Cleaned throttle body
2 Replaced the PCV valve, grommet and hose
3 Replaced the other PCV hose
4 Replaced the intake hose
5 Replaced all the vacuum hoses to the EGR valve and any vacuum hose on the throttle body.
I haven't run the numbers yet but I'm sure my mileage has improved as I was usually at a half tank ~120 miles and I'm already at 80 miles and the tank is just below 3/4. Power is greatly improved also.
Dave
I removed the throttle body and it was filthy. I also noticed that a port was completely blocked that goes to the EGR modulator.
The top view of the body.
Port "R" was plugged with garbage at this end.
Port "R" was also blocked in here. I used my welding tip cleaner set and lots of compressed air and TB cleaner to clean these ports. These holes are hard to see as they are ~ 0.030" and inside the body.
This is the EGR modulator that "E" and "R" go to.
The truck now starts fine and goes to 1200 for about a half second then drops to 800 when cold then ~650 when warm.
I don't know exactly what cured it because I did many things at once:
1. Cleaned throttle body
2 Replaced the PCV valve, grommet and hose
3 Replaced the other PCV hose
4 Replaced the intake hose
5 Replaced all the vacuum hoses to the EGR valve and any vacuum hose on the throttle body.
I haven't run the numbers yet but I'm sure my mileage has improved as I was usually at a half tank ~120 miles and I'm already at 80 miles and the tank is just below 3/4. Power is greatly improved also.
Dave