22R E Running ruff Need New Ideas

lionsbreath

Adventurer
Ok Its an 87 4Runner 22R E. It runs ruff at an idles wet or dry out side but when its wet out in runs ruff all the way around. I have replaced plugs, wires, cap and rotor. Even swapped out computers. No change! Timing marks line up rotor points to one at top dead center, but if you put a lite on it and time it out it runs like crap. In fact to make it run half way decent I have to advance the timing way out. When its wet out it seems to choke on its self and at a idle it jumps between 500 and 700 rmps. If its dry out then it just ideils a ittle ruff. ANY IDEAS?
 

ntsqd

Heretic Car Camper
How many miles on it, and if over ~125k has the timing chain been replaced?
 

DaveInDenver

Middle Income Semi-Redneck
You say there's a difference wet or dry. Do you mean rain, not rain, high humidity or not? Could it really maybe be a temperature difference?

Does it start OK all the time?

Like has been mentioned, timing chain is OK? Most people find the 125,000 interval the max the chain will go. It could be stretched and not failed, which will throw the idle off.

Rough idle on a 22R-E is usually one of a few things. Check vacuum lines first. Any dependency to the brakes being pushed or not?

The Aux Air Valve (or sometimes called the Idle Air Control) is often the issue with bad idle on a 22R-E. This is the coolant controlled valve on the bottom of the throttle body. Expensive sucker, about $150, but available at Auto Zone, NAPA, Toyota dealer and so you can shop around. I would verify that your EFI temp sender is right, if that's gone wonky it throws the ECU for a loop. Also the O2 sensor might be going out. Beyond that, the Cold Start Injector, if it's leaking, will make it idle poorly. Also the EGR valve or vacuum modulator can stick and that throws the idle off.

Might just be time to take the intake apart and clean all the black goop from inside it. If you pull off your intake hose from the front of the throttle body and hold the butterfly open it will probably look like a black hole. The inside of the intake plenum and intake runners get coated in this mixture of unburned gas, oil from the PCV and soot from the EGR. It's nasty and most people find a much better throttle response when they just clean that and the throttle body.
 
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Grim Reaper

Expedition Leader
Wet usually means high humidity and high air density (more O2) and more air temp drop when ti accelerates through the engine. If it runs better when high humidity that usually means you are running rich. Since you are running worse when wet it is probably running lean.

As Dave said...."vacuum leaks". They will play hell on this fuel injection. Any air that doesn't go through the AFM is going to throw the mixture WAY off to the lean side. Inspect EVERY inch of EVERY hose.

Just because you don't have a check engine light does not mean you do not have a code. Check them.

http://www.off-road.com/toyota/tech/codes/index.html



Valve adjustment: When was the last time it was done? If you have a couple off it will throw off the fuel load in the cylinders and it will idle bad. Run it a little tight from spec. .001 tight will quite them down some but not get you in any trouble.

EGR.

Unplug and stick your finger on the hose while it is running see if it clears. The EGR control modulator is a common failure part.
If that clears it up then test it.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=EC&P=12


TPS.

Check it. http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

The TPS's they are selling at Autozone are the real deal. Last one I bought even had the Toyota logo on it but came in a Wells box.


I have been chasing a start problem and I ran across some discussion on IH8MUD of other Toyota's that have similar FI and Fuel pressure regulators getting stuck and not dropping fuel pressure when it is suppose to...like idle. I think I have a problem with this as well. Mine runs better when wet so it seems to be rich and that goes along the lines that my fuel pressure may be too high. Trying to find a Pressure gage to barrow to check mine.

I really feel the Idle being related to the Aux Idle control would only come into play when cold starting and through warm up. Once fully warm, even if it didn't close fully you should have enough adjustment on the idle screw to "hide" the problem "when warm". If it is still doing it when fully warm I would check a few other things first but by all means check it before spending any money if you have not isolated the problem else where.
 

DaveInDenver

Middle Income Semi-Redneck
Grim Reaper said:
I really feel the Idle being related to the Aux Idle control would only come into play when cold starting and through warm up. Once fully warm, even if it didn't close fully you should have enough adjustment on the idle screw to "hide" the problem "when warm". If it is still doing it when fully warm I would check a few other things first but by all means check it before spending any money if you have not isolated the problem else where.
Good point. The easy way to tell if it's acting up is to squeeze one of the lines leading to it and if it settles down, bingo. It's always in the air circuit and if there's gunk keeping it from operating smoothly, I've been told it can make your idle pretty unstable. I dunno, I've not replaced mine and I'm chasing down a variable idle, too. I have a couple of things left, but it's sort of pointing to my AAV being bad, which is why I brought it up. Mine's got 190K miles on it for reference.
 

Grim Reaper

Expedition Leader
DaveInDenver said:
Good point. The easy way to tell if it's acting up is to squeeze one of the lines leading to it and if it settles down, bingo. It's always in the air circuit and if there's gunk keeping it from operating smoothly, I've been told it can make your idle pretty unstable. I dunno, I've not replaced mine and I'm chasing down a variable idle, too. I have a couple of things left, but it's sort of pointing to my AAV being bad, which is why I brought it up. Mine's got 190K miles on it for reference.


I'll have to find it again but I ran across a post on mud that caught my eye. FJ62 that the guy was chasing a similar idle issue to mine and what really caught my eye was this guy blew a Fuel pressure modulator (the other do hicky on the fuel rail to keep the pulses from the pump off the rail). Well I have blown one as well. I can't seem to tell a difference when I unplug my fuel pressure regulator. My truck starts AWSOME when it's 30* Hard to start at 60*...all pointing are running rich.
 

DaveInDenver

Middle Income Semi-Redneck
Grim Reaper said:
I'll have to find it again but I ran across a post on mud that caught my eye. FJ62 that the guy was chasing a similar idle issue to mine and what really caught my eye was this guy blew a Fuel pressure modulator (the other do hicky on the fuel rail to keep the pulses from the pump off the rail). Well I have blown one as well. I can't seem to tell a difference when I unplug my fuel pressure regulator. My truck starts AWSOME when it's 30* Hard to start at 60*...all pointing are running rich.
Funny, mine is the opposite. Hard to start cold, almost instant when it's warm. I'm probably running lean, but my truck is not happy with the AFM clicked more than a couple of ticks richer. I have an Engnbldr 261 cam, ported head, LCE header, 2.25" exhaust, etc. So I am sucking significantly more air through than stock and so that's why I've been messing with the dial in the AFM. At 4 clicks richer than stock, it's obviously rich and idles very poorly. At stock it's obviously lean, I get a slick knock in the summer even. At 2 clicks I think it's a good balance. It's possible mine's also related to the fuel pressure regulator, although maybe my fuel pressure is low. I sometimes think that when I built this engine I should have budgeted enough extra money to just replace every sensor and then I wouldn't be tracking down these nagging issues. But that would have been another $500 or something and didn't seem necessary at the time. Cie la vie!
 

Grim Reaper

Expedition Leader
DaveInDenver said:
Funny, mine is the opposite. Hard to start cold, almost instant when it's warm. I'm probably running lean, but my truck is not happy with the AFM clicked more than a couple of ticks richer. I have an Engnbldr 261 cam, ported head, LCE header, 2.25" exhaust, etc. So I am sucking significantly more air through than stock and so that's why I've been messing with the dial in the AFM. At 4 clicks richer than stock, it's obviously rich and idles very poorly. At stock it's obviously lean, I get a slick knock in the summer even. At 2 clicks I think it's a good balance. It's possible mine's also related to the fuel pressure regulator, although maybe my fuel pressure is low. I sometimes think that when I built this engine I should have budgeted enough extra money to just replace every sensor and then I wouldn't be tracking down these nagging issues. But that would have been another $500 or something and didn't seem necessary at the time. Cie la vie!
Are you resetting the ECM after you make adjustments? I played with one and found that when making changes I was better off resettign the ECM after each adjustment.

I ended up swapping in another and resetting. While the ECM was learning it was doing great but once it had enough time it went right back to the same complaint. :(

I hope to get over to my buddies this weekend and see if his fuel pressure gage will work on mine to see what its at and to see if the regulator is changing it when we pull the hose off.
 

Clay

Adventurer
lionsbreath said:
Ok Its an 87 4Runner 22R E. It runs ruff at an idles wet or dry out side but when its wet out in runs ruff all the way around. I have replaced plugs, wires, cap and rotor. Even swapped out computers. No change! Timing marks line up rotor points to one at top dead center, but if you put a lite on it and time it out it runs like crap. In fact to make it run half way decent I have to advance the timing way out. When its wet out it seems to choke on its self and at a idle it jumps between 500 and 700 rmps. If its dry out then it just ideils a ittle ruff. ANY IDEAS?

Did you get it fixed? My guess would be vacuum lines, as well.
 

lionsbreath

Adventurer
Thanks for the ideas. I have been a little press for time and got tired of throwing money in to parts that didn't fix it. So I took it over to the local dealer and paid a $100. to have them trouble shoot it. They said it was the throttle pos. sen. They quoted me $110 for the part $200 for labor. I just paid for the testing and will hit ebay or auto zone for the part and replace it myself. I will let you know the out come. I wonder why the throttle pos. sen. would act more when it wet out. And to aswer the question how wet does it need to be. Rain or just after the rain is when it runs ruff. If this isn't the answer I will just take it out back and :gunt: it. I did find out that the last owner disconected the the check engine light. so this must have been an on going problem. I would bought the runner anyways I just wish he would have been honestThe timing chain was sdone about 30K ago and it has about 188K on it now.
 

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