so i bought a 94 2wd 22re toyota pickup for my dad to use around the yard... it had been sitting for only a month or so before i bought it... the truck has been dealer maintained for everything including new timing chain, water pump, head gasket and all that stuff... as the previous owner said, i took it to the dealer and if they said it needed something she went ahead and did it...

i drove the truck home and for the day after and it ran perfect... the next morning i went out and started it and i noticed it was idling very rough and lopey... i smelled gas so i looked back and i could see it puffing black smoke everytime it loped... under acceleration even free revving it seems to smooth out and run great... but at idle or any steady rpm at any speed there is just a horrible miss and roughness... i drove it around hoping to clean it up and i ended up getting 50 miles to a half a tank...

i then threw some plugs, wires, cap and button on it just to get that out of the way... didn't change at all... so today i put a new fuel pressure regulator on it, nothing changed... i then put new injectors in it, still no change... all the plugs that i pulled out were pretty equally black...

i honestly don't want to just buy new everything for it if i can avoid that...

so i'm pretty much wondering if anyone has had this type of problem or if there is something specific that causes this on these motors...

the thoughts i have could be maybe an o2 sensor, afm, possibly tps, or maybe coolant temp sensor... any tips or ideas would be greatly appreciated... also there is no CEL at anytime during this...

also the temperature gauge doesn't seem to be reaching normal temperature but it was like from the start before the problem started... it is full with coolant and the heat blows very hot...

thanks in advance

-Sam

 

My 91 started running rich also. I had fouled plugs and black sooted tail pipe. I also noticed a very loaping and rough idle and a very high (2000 rpms) on cold start even when it is warm outside.

 

So i unplugged my cold start injector the other day and the problem cleared up. You may want to check on that with yours.


Sorry for the double post. My phone does what it wants sometimes.

 

Thanks.... but sorry that I forgot to mention that... first thing I tried was unplugging the dood start injector...

 

my guess is the afm, in that area. just a hunch, though. maybe the tps, as well

 

You still need to check for codes. Many of them don't light the CEL.

If the cold start injector is leaking, unplugging it won't help. Pull it out of the plenum, then with fuel line still attached, jump +B to FP and turn ignition on (but don't start). That'll pressurize the fuel lines and you'll see if it's leaking.

Definitely check the ECT since if it's bad the computer will never get out of warm-up mode (open loop). Best way to check is look at the voltage on the ECU terminal. See the Troubleshooting section of the Fuel Injection chapter of the fsm. Look for THW to be .2 to 1 volts when motor at op temp:

http://personal.utulsa.edu/~nathan-b...27troubles.pdf

Read the volts on VF1 in the check connector (when ignition is on). With no jumper set, that's the "learned value" of the air fuel mixture. (Read between VF1 and a ground - E1 is a ground in the check connector, or use neg batt post.) Normal is 2.5 volts. Less means the computer is detecting a rich condition, and is reducing fuel to try to compensate (this would indicate something outside the computer's control is injecting fuel, like a leaking cold start injector). Over 2.5 volts indicates the computer thinks the motor is running lean, and is injecting extra fuel to compensate (could be from a poor/corroded connection between O2 sensor and computer, a bad O2 sensor, exhaust leak allowing air (oxygen) to be drawn into the exhaust stream, problem with the PAIR (pulsed air injection) system, something like that.

 

I'll bet it's the AFM. If you have a multimeter, you can check it out using the instructions on 4Crawler's webpage. Mine was stuck open, running very rich at idle. I just pulled it off, wiped it out inside, made sure the vane moves freely and put it back together, the difference is night and day. Make sure to pull the negative battery cable for a few minutes to reset the computer. This is a cheap and easy check/fix and a good place to start.

 

thanks for the all the ideas guys... i finally got home from work so i am gonna head to my shop and try to knock all this out by the end of the night... i will post up any updates or if i fix it... i appreciate all the input!

-Sam

 

I checked the cold start injector like you mentioned above and found no leaks of any kind. I also checked the AF mixture value and found it was showing 0.08 volts. I checked from the battery ground and from the E1 terminal and both show 0.08 volts. Does this sound correct? I ohmed out the #3 injector which was the only one I could get unplugged and it showed 13.8 ohms which is acceptable. I ran out of time fighting with the others so I will check them later. Will ohms show different if the injector is bad or will that only check the solenoid? What other areas do i need to look too for such a large difference in volts?

Sorry for high jacking your thread.

 

As I understand it, there are two levels of adjustment rich or lean; on the leaning side, about 1.25V indicates the computer is making a moderate adjustment toward lean, and close to zero (your value), the maximum leaning adjustment the computer can make. On the richening side, 3.75 and 5 volts are the two values.

So, something is adding a lot of extra fuel to your intake air, and the computer knows about it, and is trying to compensate, but the extra fuel is overwhelming anything the ecu can do. So, probably a leaking injector, and possibly something messed up with vacuum line routing. I've heard of people getting the fuel return line off the side of the fuel pressure regulator misconnected to a vacuum line. The regulator continuously dumps excess fuel down the return line to go back in the tank. There is a continuous circulation of fuel. So if that line were misconnected to a vacuum line, a huge quantity of fuel would be poured into the intake. So check that. There are two hoses attached to the regulator: a small vacuum tube attached on top that goes to the fuel pressure VSV, and the larger fuel return line attached to the side below the vac tube. That line has a rubber section that attaches to a steel line that runs back toward the tank.

If the return line is okay, then most likely you have a badly leaking injector.

BTW checking the ohms of injectors won't tell you whether they're leaking - that just indicates that the coil in them isn't burned out.

 

I did notice alot of carbon in the plenum when I removed the cold idle injector and even the injector had alot of carbon on it. It had a strong gas smell when I stuck my eye up to the hole but I figured it was coming from the injector. WHen i tested it it didnt leak so I just chocked it up for 174k miles of buildup. Could this be coming from somewhere else? The intake track is clean as well as the throttle body. Any ideas on that one? Thanks in advance.

 

Gasoline doesn't become black sooty carbon until it burns, so the black soot from rich running will be inside the cylinders, in exhaust, plus in EGR which is fed back into the intake.

Did you test all your injectors for leaking? Or just the cold start?

 

Just the cold start today. I will try to check the others tomorrow and see.

 

This is where I am at in my 22RE build--subscribed!

I just tested the AFM and it seemed to measure within range. Before that I had changed all the vacuum lines and triple-checked to make sure they are all correct.

Cold start injector is next...

 

sorry to drag up an old thread, but did you ever solve the problem?

 

Op, did you figure it out?

(Subscribing for the volt info)

 

My 94 22re is doing the same thing. I have it in the shop right now and they said they hooked it up but no codes came up. It is running very rich, black soot on plugs. Cranks fine but anytime I let off the gas, it wants to die. Black smoke out of the exhaust as well. The mechanic I am using told me straight up he is not sure what is wrong with it. I was hoping ya'll could give me a list of things to check in order so it does not cost me an arm and a leg. I have been reading through this thread and I see some things ya'll have suggested. I also don't know what some of the abbreviations being used stand for. Again, that is why I am not personally working on this truck.