Hi to everyone, new to this form. Need help with getting truck to pass smog (1 Viewer)

[GaryJohn]

I have a 1989 pickup, 22re engine. Took it to emissions test and they said that it had a lot of unburned fuel in the exhaust. They suggested I chang out the cat and map sensor. I have done some surching and have not been able find anything about a map sensor. So does the truck have one? I also found that the oxigen sensor had alot to do with the amount of fuel is going out the exhaust. Any one have any ideas as to what to change out?

 

[pappy]

You don't have a MAP sensor. You have an Air Flow Meter (AFM). It sits on top of your air filter box. I would leave it alone. It could very likely be your CAT ($$$). I would also consider replacing your Ox Sensor (Denso aftermarket), give it an oil change, make sure you have a fresh air filter, give it a tune up (spark plugs, wires, dizzy cap & rotor), adjust your valves, and lastly check your timing. It's not uncommon for these trucks to get timed at 8* BTDC for a bit more power. Time it at 5*.

Good luck with the CA smog nazis. I don't miss them.

Where in the eastern Sierra?

 

[gnob]

Show your results.

 

[MaK92 4RnR]

If you post your results (cover your personal information) we'll be able to point you in the right direction. My 88 4Runner fails at least once every year for high nox

 

[KLF]

Ditto on adjust the valves.

 

[pappy]

I think we had another drive-by.

 

[GaryJohn]

You don't have a MAP sensor. You have an Air Flow Meter (AFM). It sits on top of your air filter box. I would leave it alone. It could very likely be your CAT ($$$). I would also consider replacing your Ox Sensor (Denso aftermarket), give it an oil change, make sure you have a fresh air filter, give it a tune up (spark plugs, wires, dizzy cap & rotor), adjust your valves, and lastly check your timing. It's not uncommon for these trucks to get timed at 8* BTDC for a bit more power. Time it at 5*.

Good luck with the CA smog nazis. I don't miss them.

Where in the eastern Sierra?

Big Pine

 

[GaryJohn]

Big Pine

Thanks for the reply. I have since discovered that the 02 sensor is not connected and i can not figure out where it plugs in. I have changed the oil, put in platinum plugs, new air filter and a few other things that were missing . Have been looking on line for a picture of the motor compartment that shows where the 02 senser is plug into. Any ideas

 

[gnob]

The o2 should be roughly under the drivers seat.

 

[pappy]

Thanks for the reply. I have since discovered that the 02 sensor is not connected and i can not figure out where it plugs in. I have changed the oil, put in platinum plugs, new air filter and a few other things that were missing . Have been looking on line for a picture of the motor compartment that shows where the 02 senser is plug into. Any ideas

I have a 1985, and I'm not as familiar with the 1989. As best I can tell your truck might have two Ox sensors. Mine is on the exhaust manifold, and plugs into a connector on the fender. If you have a second it will be downstream past the CAT.

Something else. Some folks act like Ox sensors are a smog device, and unplugging them is a good thing. The reality is they are part of the fuel injection system, and an integral part of making the system work efficiently.

 

[pappy]

Big Pine

I know some folks in Bishop (the Sextons), which is why I was asking.

 

[Mudder]

1989 has one O2 if its federal, not sure about California and it was before the cat. The wire it connects to runs down with the transmission harness if you have an auto.

 

[TYM4FUN]

Just want to add, you should not return to that shop. They performed an inspection and missed the O2 connection, then proceeded to guess which components you should replace.

 

[GaryJohn]

I have done a little searching and found out that the 02 sensor helps with the computer to get the right amount of fuel and air. I drove the truck about 180 miles to get it checked and it used 3/4 of a tank of fuel. I think the shop did not do an inspection just put the sniffer up the tail pipe and it said that there was way too much fuel coming out the tail pipe. They only had the truck in the bay for a few minutes. The sessor is in the exhaust manifold and there does not seem to be a wire on the DS fender to plug it in to. Will have to look harder for it. I sent the guy I got it from a text and he said it allways passed emisions. I dont see how since I have found so many things wrong with the emissions system.

 

[Mudder]

As Pappy said, the O2 sensor isn't emissions equipment. If its unplugged there's one of two reasons, there's a problem with it/a problem with the wiring or someone who has no clue what they're doing has touched that truck. But if it is the O2 sensor and the check engine light isn't on I'd be concerned about that too.

 

[pappy]

I have done a little searching and found out that the 02 sensor helps with the computer to get the right amount of fuel and air.

Exactly. Your mileage will be crap without it.

The sessor is in the exhaust manifold and there does not seem to be a wire on the DS fender to plug it in to.

Look for a wire/connector below the brake booster.

 

[TYM4FUN]

As Pappy said, the O2 sensor isn't emissions equipment. If its unplugged there's one of two reasons, there's a problem with it/a problem with the wiring or someone who has no clue what they're doing has touched that truck. But if it is the O2 sensor and the check engine light isn't on I'd be concerned about that too.

I believe he ment to write ~most people believe it is an UNNEEDED smog device~

The O2 sensor is indeed an important emissions component for that vehicle. It monitors and reports back to the ECU the amount of oxygen in the exhaust. The ECU then decides how much fuel is needed to keep the A/F ratio accurate (**added>>) and for correct catalyst operation.

With the sensor not connected, the system stays in open loop and runs very rich, hence the excessive fuel usage.

 

[pappy]

I believe he ment to write ~most people believe it is an UNNEEDED smog device~

Nope, not what I meant to say.

Emissions equipment on our trucks include the EGR (Exhaust Gas Recirculation System), PCV (Pollution Control Valve, or ventilation system), and catalytic converter. That's it on the 22RE. On 22R trucks you can add what is commonly known as the Smog Pump, or Manifold Air Injection System.

None of these deal with fuel management, but rather cleaning up the exhaust after the fact. These systems are frequently identified as being power robbers, and deleted by owners in non-smog nazi states in a process affectionately known as "de-smogging."

The Ox sensor is part of the EFI fuel delivery system. Unfortunately, some folks think is an emission device and do something stupid with it. I see your point that anything that improves fuel delivery also improves emissions. But the bottom line is the Ox sensor is not part of the emission system.

Also, for chuckles … California 22R engines had an Ox sensor. Go figure. If it failed it messed with fuel delivery somehow to the carburetor and the truck would fail CA smog. BTDT.

 

[gnob]

Stop the mis information.
The o2 is indeed emissions. It is the number 1 emissions device on the vehicle.
WTF.

 

[pappy]

Stop the mis information.
The o2 is indeed emissions. It is the number 1 emissions device on the vehicle.
WTF.

Bzzzzz, wrong answer. From the Factory Service Manual.