1986 4runner engine will not idle please help!

Alright so here we go I noticed that my 4runner was starting to run a little warm the past few days and decided that it was time to look into the cooling system a little bit. My 4runner is an 86 22-re

I have since replaced the following:
Thermostat
All radiator hoses
Water pump
and lastly head gasket.

I replaced all the of the parts in that order after diagnosing that they were of no help keeping the engine cool. After replacing the head gasket I had the head professionally machined and completely gone through and rebuilt. I have put all the parts back together set the timing and now it will not idle. I have to keep giving it just a little throttle to keep it to where it wants to idle. I didn't take anything off or disconnect anything other than what was needed to take the intake off in order for me to complete the head gasket project. The engine will rev like no other now and is very strong since the rebuild but as I have stated it will not idle it just chokes itself out. Any help would be greatly appreciated I am just confused as to what would be the cause of this as I have never heard of this problem. Thanks in advance!

 

I would look at valve clearances and vacuum leaks...and I would also verify ignition timing.

As for cooling, have you EVER replaced the fan clutch?

Now is the 86 carb or FI?

Howard

 

+1

check your vacume hoses!

 

I have checked for leaks and was able to set the correct valve clearance it will run smooth and very quiet since the rebuild but just wont hold an idle I am almost certain that the timing is set properly because while I am reving it and holding a little throttle to it nothing seems out of the ordinary but once I left off the throttle it sputters then dies. Also to answer the question 86 is a fuel injected.

 

is it pulsing or just wont idle? have you tried turning idle up a little?(50 or so RPMS)
if the timing was off it should run funny not just no idle?

 

It has no idle at all just burns what fuel I guess is left to burn after letting off throttle then dies. I havent tried turning up the idle yet I am just confused as to why it would be acting like this now if I hadn't messed with anything other than having the head rebuilt and installing new gaskets ??

 

sounds like vacuum leak. checked fuel filter as well?

 

I sprayed around all my gaskets to see if I had a leak there but I will check with the vac lines but I am pretty sure I am all good there as well but I will double check to make sure. I haven't checked the fuel filter but would this be a problem since I am able to rev it and it will continue to run just needs assistance with idle like I have to add about 500rpm to throttle to keep it idling

 

If they done head work than its possible they have a vacuum line crossed or kinked. It doesn't take much to interrupt they vacuum system. It really sounds like vacuum if it idle before work. if truck is running good other than idle I'd start checking vacuum lines.

 

Thanks for all the help everyone! I will go and double check all my vac lines this seriously has me confused as to why it worked perfectly before even though the head was in bad shape and now that I have all new parts it runs like crap

 

Also pull off the oil fill cap... check to see if there's blowby (air pressure coming out of the oil fill tube). Still sounds like a vacuum line issue to me though

 

Alright I will check all this once I am able to get back to my shop where my 4runner is located.

 

heck you are almost local to me, I live an hour north of Asheville...I would look at the quality of each vacuum line and where it terminate, it could be that a vacuum line got unhooked at the other end...or a dashpot or somesuch got damaged.

Also, turn you idle up while you trouble shoot, the engine with a good sealing valves needs a far different fuel/air mixture now.

And one last thing, I had a idle issue on the same motor that was VERY hard to trouble shoot and it was a bad coil, so make sure all your electrical grounds are good and double check your coil, coil grounds and secondary wiring.

Can you stick a vacuum gage on the motor and watch it while someone else keep the motor running, just above idle?

And could this be as simple as nothing more than a throttle cable adjustment?

Howard

 

Yeah I live about an hour west of Asheville...I will check all the lines and make sure that they are connected and not damaged. Hopefully it is something as simple as turning up my idle speed a hair I mean I just barely have to move the throttle in order to keep it running at what I would consider to be a normal idle I mean other than that this thing is a real runner nnow with the head rebuilt. A friend that works on these engines says he hasn't had such a quick rev response like this ever.

 

Alright so I've checked all vacuum lines and adjusted the idle speed with no success at keeping an idle. Very stumped at this point to what could be wrong with it not wanting to keep an idle.

 

Is it running good besides the idle?

 

yeah runs real strong just no idle

 

If it idle good before head work I would look over what they done. i.e.- check intake make sure it's not cracked, throttle body, make sure there is no vacuum line missing... Just have to look an play.

Do you have RPM gauge? What is the RPM trying to idle?

 

Well thanks for the NEG REP whoever?

 

Did you check to see if you were getting blowby from the oil fill tube while the engine is running?