NoLookingBack

here are the details.

1980 20r stock 4x4. 125K miles on the engine.
Full tune up with plugs, toyota wires, cap/rotor Timing at 5 degress BTDC
All vacuum lines present and accounted for. No leaks that I can tell of.
Have tried 3 different ignitors/coils all with same result.
Carb shows full of fuel when symptoms begin
Fuel filter changed and shows plenty of fuel when symptoms begin.
Choke has been confirmed working properly
temp outside is anywhere from a nice 68 to 90's

I am at my wits end :cry: and ready to

Truck will start fine at any temperature and will idle well. Until you hit the gas and then it will die. ( on the way down in the rpms)

Will start back up but sometimes its a hard crank sometimes, like the type you get when you are off on the distributor timing by 180 degrees.

Will run for a while and then at higher than idle rpms starts to sputter and burble as if its running out of fuel. Sometimes will get worse and then correct itself. other times bucks and stalls like mad. Other times, it will run just fine with no burbling, no stalling and none of the issues spoken about... its very erratic

It wil then start but only with a pumping of the gas and then hold it down wide open. Then it will continue to stall and die on let off of gas. It sputters but does run when you continually hold down the gas but the more load you put on it ( ie. the faster you go) the worse the sputtering.

Pulled the plugs and they look fine. Not carboned out nor pure white..

I am stumped.

trx125

Check fuel pump! Mechanical pumps the arm maybe sticking or just wore out! Just my .02

NoLookingBack

But there is plenty of fuel in the carb float bowl window! Thanks for the idea though.. One important detail I left out was that it had a full header and bypass pipe for the cat converter until I bought it.. The guy changed it back to stock and I put on a new converter. The problems did NOT appear until about 2-3 weeks that I had it and the alternator blew along with the regulator. These have since been replaced. and I only replaced the Cat 2 days ago.

trx125

Float may be sticking! just something to check. Also check the vacuum advance on the distributor!

jimbo74

check that the cam timing is set to 0 and the crank timing is also 0

every so often, my trucks timing chain skips a cam tooth or 2 and it runs like what you are decsribling until i take the valve cover off and realin the 2

NoLookingBack

but half the time it runs fine... that is what is so frustrating... the problem must lie in something that is dynamic... if it were the timing chain, it would do it all the time...

I appreciate your response to my other question regarding the 22r carb... do you think that changing back to the stock exhaust system from a full header and no cat could have done something? But its been 4 weeks since that was done and the truck passed smog with flying colors!

It really does seem like its not getting enough gas... or perhaps the distributor is not advancing... How can i test that? I took off the hose and created vacuum and you could hear the plate move.. If I took off the cap, should I also see it move?

jimbo74

plug the distributor lines, it relies on vacuum to advance....

on my 22r, when you set timing, you are supposed to have the distributer vacuum lines plugged

also i am not 100% sure on the setup of the 20r, but on my 22r, i plugged a couple things below the carb and it runs a lot better

as far as it being a timing issue.... it might still be... it would run fine if i was just driving conservatively, but its when i would gas it hard that it would sputter and bog out almost dying

NoLookingBack

this is just sporadic. will start fine most of the time. run well for about 15 minutes and then it starts with the missing, dying, stalling bucking and feeling like its starving for fuel. No black smoke at all out the pipe. It will idle at a light for a minute or two and then die as if someone turned off the key. Have to pump the gas and floor it to open the throttle plate and then it starts... Drive it long enough this way and sometimes it works its self out and runs fine for about 10 minutes or less and then starts in again... I am going mad trying to figure this out

jimbo74

check your vacumn and look for leaks... i know kyle has mentioned that people retofit webers onto the 22r and the manifold spacers leak like crazy and allow air it... have you tried spraying starting fluid not in the intake but around the carb and manifolds t osee if there is a change in running?

NoLookingBack

check your private mail.

kyle_22r

sounds like your idle solenoid might not be working -- that'll cause an engine to sputter and die when it's supposed to idle.