Ok so I get a rough idle. I have checked the timing it is dead on, replaced the PCV valve, correct ign. wiring, adj. idle to 800rpm when I set the timing, air vent is clean. I adjusted the TPS slightly and truck ran smooth for 2 days then started back up. I cleaned out the EGR vacuum modulator. I tried to test the EGR but what hose do I pull off to test it? Book says to pull vac line from intake manifold where TF is that. I am not seeing a line that would reach to it. Do I have to run a line by it self? Doesnt make sense since then the hose I pull off wouldn't be hooked up.

Basically has rough idle and when I let off the gas coming to a stop it will stall but not every time. Sometimes it goes down to about 200-300 then back up to 650. Even after I set the idle to 800.

I swear I am not drinking (or at least not that much) and I think the idle screw turned while I was driving so I adjusted it back again.

Please help this is killing me! Wanna go out but don't need my truck stalling on the trail all day long.

 

did you use an ohm meter to check the tps? how do your vacuum lines look, any cracks? is it using water?

 

Not using any water. TPS had yellow mark on top and on screw that were not lined up. I lined them up and it ran better. this motor is brand new only has less then 10k on it.


Heck the pic to the side was the day I spent 6 hours detailing my truck to have the engine blow only a hour after. Still hurts to see that pic. I need to update that. haha

 

have you checked the dashpot?

 

Ok so i am missing the filter end on the dashpot. is there supposed to be vacuum on it at all times ? I don't feel any vacuum at idle or when reving. What exactly does the dashpot do?

looking right now for a new one.


Ok just read what it does and checking it right now.

 

Ok so I warmed the truck up and it brought it up to 2500rpm pinched hose and it held at 1600rpm. I can adjust it when I get home I don't have the tools here at the office. I read that it should hold at 2000.

Also should note when i cleaned out the EGR vac. mod. it was really dirty. I blew it out with my compressor the best i could. Can you buy a new filter kit for it or do you have to buy the whole thing. dealer wants 65 for a new one.

 

i don't know id you can buy a new one or not.

 

Does anyone know which way to adjust the dashpot? Do you want the dashpot some what compressed or not at all. If you turn the adjustment screw down it compresses it if it's up it barely taps it when you let off the throttle.

help please

 

Although I don't know how to "adjust" one I do know that turning the "dash pot adjustment screw" on the throttle arm thingy up enough that the DP no longer touches it helped me a ton. I was going to take it off but decided to eliminate it's activity first. I'm idling much better now. I know it has a purpose and will eventually get it adjusted right or replaced but for the time being I needed to eliminate it so I my idle would calm down.

I hope this helps you make an informed decision even with the made up terminology.

 

Well I turned it down putting more pressure at idle on it and brought the eng. to normal temp. Brought the idle to 2500rpm and pinched the vac. line coming out the bottom of it. I got it to the point where it holds at 2000rpm when pinched. Thats what I read it should hold at when pinched.

You might wanna try that and also adjust the idle screw to bring the idle down. I have mine set at 850-875 area. I like it better truck idles smoother then at 750 you can feel it shake.