truck will not idle and bucks under half throttle under 2000 rpm. (1 Viewer)

[mongoose2231]

K so this morning I blocked off all the egr ports and I pinched every air rail inlet. There were holes everywhere in the air rail. I then disconnected the air pump hoses and she holds idle but fluctuating. Not a healthy idle but rather vroom vroom as if it had a hot cam. I think I will seafoam the carb and if it improves then I will desmog and call it a day.

 

[FJ40Jim]

The rusted out AIR rail has no effect on how the engine runs. AIR system is all post-combustion.

Adjust the idle mix screw so it is 4-5 turns out from bottom. Do not do a lean drop adjustment, that is for best endgas quality to the cat, not for best idle quality.

If it still runs like poo, then there is probably a fuel shortage, either a vacuum leak or restricted carb idle circuit.

 

[mongoose2231]

OK EVERYONE, PROBLEM SOLVED!!!! I finally have a properly functioning truck that holds idle beautifully. What was the problem? I am inclined to believe it was a dirty carb and the like. I ran Seafoam through the motor, fuel system and the vacuum line off the booster. put some in the gas tank and let her run for a couple hours at 1200 rpm with the choke pulled. It now idles beautifully. finally i have a good running truck again. the air rail is disconnected and i plan on replacing it. everything seems to function normally. thanks to all for all their help.

 

[erall0]

i had the same problem purchased a new carby manifold distibuter plugs and leads couldent solve the problem turned out to be points lol

 

[FJ40Jim]

The OP's truck is equipped w/ solid state dissy instead of points.

 

[brett76]

hey jim what vaccuum is the line to the distributor supposed to be pulling? just found my vtv is bad. i pulled it and ran the line straight to the dissy. how long can i run this or is it bad to do at all? the vaccuum even like this is barely even distiguishable. does that sound right?

 

[mongoose2231]

ok, so after a few weeks of driving, the truck is perfect. couldn't thank everyone enough for their help. now on to tackling rust and installing an air conditioning system, courtesy of fellow forum member i purchased from. that is what i'll need help with.