Hi everyone

I recently put a second hand engine in my 1990 22R 4runner. The engine is 93+ (had a smaller flywheel) and from a hilux. The engine put in with fresh clutch, my intake, my carby etc and all my smog gear.

My 4runner was running, but blew a head gasket and had been sitting for 2 years without any preventative maintenance like fuel stabilizer etc.

Before starting, I siphoned out 40L of the bad fuel, and put in 40L of premium, so it was about a 30% old fuel. The fuel didn't smell stale, just smelt like New coil, then no fuel past the fuel pump. It run after putting the new engine in, turns out the coil was dead, no spark and resistance test confirmed. New coil and we had spark, but no fuel getting past the fuel pump. I swapped my old fuel pump onto the new engine, then fuel was getting to the carby, but not filling the float bowl. It would run with fuel poured directly into the carby. I took off the sight glass and fingered the float around, and dumped a bunch of carby cleaner in there. After it ran, and fuel is filling the float bowl.

I ran a couple of cans of carby cleaner through it, but it would not idle. I noticed it was misfiring on cyl 1, pulling the plug would cause no difference in how it idled. My dizzy cap was in very bad condition and corroded, so a new cap and leads went on and that solved the misfire, but it still doesnt idle well.

After that I thought maybe it was still poor fuel, so I used up 40 litres and filled it back up, it would have now 5L/60L of the old fuel, so I don't think that would be the issue.

Symptoms:
- Does not idle well
- I can tickle it into idling by playing with the throttle, then it will idle around 1000 rpm, but die occasionally
- No difference with warm or cold engine
- Stalls when braking
- The float bowl level is at the top of the sight glass, too high?
- The RPMs hunt around a little
- Runs good when driving around, power seems to match what I remember

I suspected the brake booster may be gone causing the stalling, in fact I can stall it by pumping the brake stationary. After plugging the brake booster vacuum hose I can no longer stall stationary, but it still stalls when moving and coming to a stop.

Things I've tried so far:
- new dizzy cap
- new rotor
- new leads
- new plugs
- new coil
- new fuel filter
- Swapped my distributor onto the new engine and set the timing, no change
- Checked the resistance of the pickup coil. The FSM says around 180 ohms, I'm reading around 230 but that reading matches the old distributor too, I think they added more windings to the coil at a later date.
- Checked the pickup coil gap, 0.4mm
- Set valve clearances, no change, they were pretty okay to begin with
- Checked fo vacuum leaks with starter spray.. couldnt detect any
- Replaced all the 4mm vacuum hoses with fresh ones
- Checked the fuel cut off solenoid and it is functioning, but I replaced it with a bolt for now anyway.
- Blew out the fuel cut off solenoid channel with air.
- Checked for a stuck EGR by tapping it with a screwdriver, the idle does not improve. Manually sucking on the vac line to open the EGR causes the car to stall, so I guess the valve works, and is not stuck.

When checking the fuel cut off solenoid, I noticed mine doesnt have an oring on the end of it anymore... I've heard it can get stuck in there and disrupt the idle fuel circuit. I tried blowing it out with an air gun but am yet to locate the oring...

I suspect it's a blocked idle jet, are there any other thoughts? Can I check / clean the idle jet without buying a rebuild kit?