ok so i have been trying to figure out this problem for some time now. I have a major loss of power, hesitation, miss, and rough idle, the truck was running fine, and gradually got worse. I thought it could be timeing chain so i replaced the head gasket and timeing chain.no difference, i have also replaced mass air, plugs, wires, fuel filter, fuel pump,distributer, distributer cap, air filter, o2 sensor, tps, i have new exhause header, 2-1/4 to flowmaster 40 with no cat....i'm hopeing somone can help me as i have been dealing with this problem for far too long.....the truck is an 86 extra-cab sr5 with newer 1989 motor and harness installed

 

adjust your valves and ck your egr stuff

 

Sounds like your running on 3 cylinders. I had an 88 that had a bad injector wire. Verify your injector signal with a noid light or a multimeter at each injector.
There is also a group of wires that are by where the intake manifold sections come together that is to be grounded. They come together to a hoop that is to be bolted to the intake manifold for grounding. The wires are all red (3 I think). If they are not grounded it will run like crap.
Also check that your ignition coil is not cracked. Run the truck at night time and look for arching around the coil and wires. Make sure that the bracket that is holding the coil and igniter pack has a good ground to the fender. Take it off and sand the mounting point. The igniter grounds through the case.

 

it is running on all 4 cylinders just very rough with a miss and it backfires through the intake and exhaust i think i am going to get rid of all the egr stuff as i don't need it

 

remember that the ECU was engineered with the EGR in place.

have you checked the PAIR reed valve?
the IAV/AAV under the distributor is operating properly?
there is no corrosion and the connectors are seated properly around the igniter?

 

not sure what the pair reed valve is or IAV explanation would be awsome

do you recomend eliminateing the EGR or is it going to make my check engine light come on ?

 

the three red wires are grounded to the intake manifold

 

which 3 red wires?

 

those three red wires i think there the grounds for the injecters...

 

i had a similar issue on my 04 tacoma. it was shortly after running that cheap arco 87 grade gas. only saying cheap because shortly after, my check engine light came on. the code said too lean. reset the code and then switched to chevron 89 and used some fuel injection cleaner.

the light never came back on and my engine has been running fine ever since. not trying to sell chevron by all means, but maybe its the gas your running or maybe your fuel filter?

hope you found the issue

 

update, it was idleing fine befor i did the timeing chain and head gasket. The old chain was skipping teeth and needed to be changed. So I changed the sprokets, chain, head gasket, and head bolts, the head was pressure tested and decked. After it was finished i had troubles getting it to idle properally. I phoned a friend, he came over and got it idleing like before by jumping the chain 1 or 2 teeth. After takeing it for a rip I was still lacking power. I took the truck to toyota mechanic, (works at dealership but does side jobs) he tested and adjusted everything. He then recomended i get a new fuel pump as mine was on it's way out aswell as an 02 sensor. He explained to me that because everything was tuned to spec the motor would run worse until i changed the problematic parts. I proceded to change the fuel pump and 02 sensor to no avail. The truck idles the same, the only difference was a little more power and throttle response.

 

with all due respect, could you add commas and periods to your post so it makes more sense?

 

sorry about that post fixed

 

Hi,

Backfiring is timing. Somewhere, something is out of time. You mentioned you intentionally skipped a tooth?!!? Has this been fixed yet?
This is Obvious but is often overlooked as too obvious, depending upon the wires switched, a engine will run, although poorly, with the firing order messed up at the distributor.

Dave

 

I'm with djkeev, sounds like a timing issue owing to the backfire. Is your exhaust manifold loading up with fuel/glowing? Did you replace the exhaust gaskets, ensuring you have no leaks? Any codes thrown from ECU would help.

 

How about water in the gas tank?

Have you put a vacuum gage on the engine at idle and warmed up to see what the gage indicates? Report this back to us.

ECU has poor ground or defective?

I had an injector basically quit working. Was evident by the very lean looking #2 plug. Go run your truck for 30 minutes and then pull all plugs and hope they all look the same. A really clean plug is indicative of a weak injector(s).

Check battery ground point and engine to chassis ground wire for poor connection, i.e. corrosion.

Check to see that distributor avance is properly working with timing light.

Let us know what you find.

 

I agree. Punctuation makes the difference between:

I helped my uncle jack off a horse

and

I helped my uncle, Jack, off a horse.

 

after i took it to the mechanic, i thought that the reason it could be idleing rough is becuase of the advanced chain. I put the chain back to spec and retimed the engine. The only difference was more loss in power. I am positive it is not the distributer, cap, or rotor as i have changed them all. I don't have a vacume tester how much are they, and how do i check for vacume?

the ecu is not the problem i have already changed it out. How is the ecu grounded?

the battery is properally grounded to chassis.

as far as water in the tank, i doubt that is it because I have run a few tanks of gas through it with no change in idle.

the exhaust header is not glowing red and there is no leaks in the system.

i will check the codes and post what comes up.

would it help if i recorded the truck running so you can hear it?

 

ok, so i was out tickering with it and the vacume lines are all messed up. Lots of lines in the vacume rail that run between the head and intake are clogged, or almost clogged. Doese anywon have a vacume diagram for an 89 22re? Where can i get new vacume hoses and vacume rail?

 

you don't have the vacuum routing diagram on the underside of the hood?