Ok, so my other thread was getting long and hard to keep up with but I know one of you has the answer, so here it is again.

1986 4runner 22re. It starts fine every time, but dies when I take my foot of the gas. right before it dies I here a click come from the ECU. When Im accelerating it stumbles and hesitates badly. It doesnt matter if the engine is warm or not, and doesnt matter what the temperature is outside. It always dies at idle and always stumbles during acceleration. plugs, wires, distributer, coil are all good. Compression is 155 all the way.

It happened very suddenly, from perfect to crap in one second. I cant find any blown air hose but that is what it feels like. Put your thinking caps on guys because the last thing I want to do is admitt defeat and go to a mechanic.

 

With it being sudden, it sounds like a connection. Check the two plugs on the front of the engine:



The brown and green plugs are what you want to check.

Rob

 

I think this was addressed in your other thread I think I read earlier, but have you checked the air intake hose from the filter to the throttle body to see if it is sucking air? I was having almost the same issue with my 84 Camry on on acceleration and it was a split in the air intake hose. I had already checked it one time and apparently missed it. Looked again the other day out of frustration and the air intake hose was split but barely noticeable. I taped it up for a quick fix and all is well.

 

main air intake tube is fine.

 

Oh well, if it were only that easy.

I re-read your other post and you mentioned the K & N filter. I never had one, but I understand those are oiled.(?) Perhaps some oil has fouled the MAF sensor? Even if it did, I don't know if that would cause your symptoms though.

Just a thought.

 

I really didn't read your other post so I don't know what was covered but here are some things to think of.

Vacuum leak somewhere in the intake system.
Check for obstructions in the intake system. Once I had the same problem you did and it turns out I sucked up a "disc" off of the front grille of the truck that blocked off most of my air making the truck run very weird.
You may have had something go out, like an injector.
Another thought is that it isn't getting enough fuel, when did you last change your fuel filter? Maybe your pump or a relay is going out?
Cold start injector sticking open?

Just some ideas I had.

 

I'm lookin' at a schematic of that engine here. By-passing the EGR looks easy,not done as I told ya though. Just three bolts hold it to the EXHAUST MANIFOLD, with a gasket between. Thats not the hole ya plug. It looks as straightforward as just stoppin' up the metal pipe to the INTAKE, you don't have to to a thing to the EGR, for just testing. If it's not the EGR, testing it like this you'd see no improvement. Ain't no good at explainin' things am I. Don't you talk 'bout quitin', so help me I'll...

 

There is an intake hose that is kinda pinched, a big fat one going into the plenium right below the cold start injector. But I think it has always been pinched.
Would a cold start injector failure cause it to die at idle? Even coasting at 65mph? Would a fuel blockage cause it to die?

 

No...on the cold start injector question. You'd just have trouble starting it cold. A fuel blockage would cause it to die, but since you never have trouble starting it, then that's probably not it....and considering the click you hear. I wonder....did you ever test your TPS? Your coolant temp sensor?

Is the enging running rich? Lots of carbon at the tailpipe?

 

Not gonna let this thread die on ya. SOMEBODY help this dude out here. I wish I knew better how to explain how to remove the EGR and seal the intake, to diagnose whether it's good. The other recomended test won't work if it's failed as I suspect.That method checks if it is opening. What I'm sayin' ya do, checks if it is closing fully. ANYONE out there have ANY idea what I'm talkin' about here? Save this guys ship!

 

Yeah, I do...but, if he would bypass the EGR system(temporarily plug it off) and the condition changes that would be a prime indicator if it is EGR related. Thing is, I don't believe it's EGR related because if it were not closing and stuck open it would run better once it's warmed up. Plus, the clicking from the ECU doesn't sound like EGR, either.

 

Phew!! Thanks for your point of view, duly appreciated. I get a click when my starter won't budge, I jus' whack it good to make it spin. Was thinkin' starter solenoid on that, got no clue why you get clicking. Hasn't happened since I cleaned battery connections. Try that, might take your mind off things, 'till we get that other thing figured, couldn't hurt any.

 

I tested my TPS the best I could according to the FSM and Haynes. I also tested as other people suggested by disconnecting it and seeing if there is any change, which there was not. Funny though, my AFM is off from E2 to Vb, ohms supposed to be between 200-400 but instead would flash a random number of like 80 the go to 0.
Again as others recomended, I disconnected AFM to test for a change but then it would die if I gave it gas. So...still have no clue.

 

Okay, I've been through the wringer with TPS adjustment and replacement and readjustment only to find my my engine coolant temperature sensor was bad. Granted, this was on my 3.0, but it would still apply to you. Would you give that a shot? Unless, you like running in circles?

 

Ill try anything at this point. Where is it located?

 

Check'um here'um...lol! Good luck! I know it's frustrating.

BTW, the brown one is the cold start injector timing switch and the other is...(drum roll, please)?

Just joshin'! But, check the connection for corrosion and pull the sensor out. Plug that hole, too, for the coolant. If the sensor is all funky, rusty, and green, try cleaning it with steel wool or fine sand paper. Plug it back in (if the wire looks good) and see if it makes a difference. Again, good luck!

 

 

ooooo....thats a nice diagram. But how would a bad water temperarure sensor cause the engine to hesitate during acceleration and die without gas applied?

 

EGR, how else, any challengers if he ain't got with the temp sensor? I am truly dying to recieve some well earned confirmation. Or, learn from a master. I will admit defeat graciously.

 

That water temp sensor is for the computer, not the guage on the dash. The computer uses engine temp for air fuel ratio.