[aptosca]

Having trouble diagnosing why 1986 22R engine running real rough at idle and semi rough while driving. Diesels badly when shut off. Checked all the obvious; timing, all new ignition parts (cap, rotor, plugs, wires), fresh 91 octane gas, vacum lines appear ok (shot carb cleaner around... no leaks detected). Set valves to .008 intake and .012 exhuast (warm/hot).

How I got here... My son was driving and noticed engine getting hot. Well, it was the known Toyota 22R problem whereas the timing chain breaks the guide then starts chainsawing away at the timing cover until it breaks the water jacket wall. Yep, oil in the water and water in the oil. Sent the head out and had it rebuilt anyway. Put everything back together and now we have the dieseling at shut down and the rough idle and rough (slight) while driving.

One of the things that I noticed when tearing down the motor was the mixed oil & water got sucked up by the PCV into the carburator. There was chocolate milk all over the throat of the carb. It took my son and I about 4 weeks to get the engine back online and I'm wondering if perhaps too much time lapsed letting the milk sit in the carb.

Timing 0 degrees at 950rpm with distributor vac lines plugged off.

There is no smoke.
Engine has good response from idle
Engine has good power while driving.
No noises apparent
Exhaust is clean

So if anyone has had a similar experience and found a solution I would really appreciate hearing from you!

Thanks.

 

[Krusty]

Recheck for Vacc leak !!!!-------(and cracked lines)

 

[qsd-dan]

Isn't timing supposed to be 5 degrees BTDC at 800 RPM? Check the vacuum advance module for any leaks by individually sucking on each one of the hoses leading to the diaphragm. My truck started pining one day and I chased it down to a leaking diaphragm on the inner vacuum advance module.

 

[aptosca]

Replaced ALL vac lines (thanks Krusty) and actually found one going to the distributor to be bad. Don't know why spraying carb cleaner around didn't catch this. Then re-timed 0deg @950rpm per the book. Still a little rough.

 

[aptosca]

5 btdc @ 950 is spec. Put a vac guage on the outter distributor vac line and it's good. Put the guage on the inner (closer to engine) line and there's zero pressure. This may be correct, dunno. Went over everything again... still crap idle and dieseling on shut off. The vavles have been adjusted but maybe they're still off? Anyone have rough idle/dieseling caused by sloppy valve settings? Thanks.

 

[subliminaltrips]

mine dieseled with the valves sloppy. once i adjusted them the diesling stopped. im running a weber 38 also an i believe im running slightly lean on my main jets. also an exhaust with too much back pressure can cause this too. most of the time diesling is due to a lean condition. check the egr as well. ive heard of people dropping down to a colder plug or adjusting the gap a little to help with this issue. bottom line is something changed or is out of adjustment and should be fixed.

 

[rickballard]

timing fixed mine also vacuum leak found forgot to put small vacume line back on undo

The timing on the 22r carburatated model should be 0 degrees at 950 rpm

 

[yotaman4of20]

I Know how to fix it

Having trouble diagnosing why 1986 22R engine running real rough at idle and semi rough while driving. Diesels badly when shut off.
now we have the dieseling at shut down and the rough idle and rough (slight) while driving
So if anyone has had a similar experience and found a solution I would really appreciate hearing from you!

Thanks.

WEve had the same problem on our 81 yota pickup 4x4 22r 2.4L,. it drove us mad for over a year. running rich, diesels, black smoke, poor MPG, shaky idle at center speeds, ect...... we too replace almost everything (cap,rooter,plugs,wires,O2 censer,vac lines ect..

BUT. its the aap diaphragm in the back of the carb,. a simple carb rebuild kit will have one (about $30.00 anywhere) an you should only have to pull the carb. an put just the new aap diaphragm on an it will be good to go...we just did this today, an all the problems instantly stopped! runs like new! we didnt even rebuild the rest. just the diaphragm
an the new one will be made of ethanol resistant material.
If you hold your old AAP diaphragm up too the light yoll see pen head too pin sized holes in it.
THIS IS FROM THE ETHANOL! its dried out an is braking down an eating the diaphragm which is now allowing fuel to enter the VAC lines an system with is causing all of you problems.

The ethanol blended fuels they are putting out Eats at all the seals gaskets an hoses in old vehicles. not made before 2010, this is why so many people are having fuel related problems. an will in the future! For people who dont drive them on a daily basis they need to put fuel stabilizer in or the fuel will separate an turn to varnish in your tank... an rely mess up the fuel system more. casting you money in fuel filters an other replacement parts.
the stabilizer is good to use in all things that use the new gas. lawn mowers line trimmer ect. 3$ in stabilizer can save you alot of carb cleaner, rebuilds, plugs an hassle..

I hope this helps you an lots of others, so they quit racking there brains over this as we did...