looking for help with my FJ80 3FE, built 3/1992, CA emissions check engine codes 25, 26, and 71, 356,000 miles (2 Viewers)

[boobaa]

My first post, so take it easy on the new guy.

1. Bought my wife a 2000 LC, now has 318,000 miles, runs perfect, rustproofed, did all scheduled maintenance, 3 timing belt changes, 2 front wheel bearing changes, 1 rear wheel bearing change, 2000 to 2004 oil & filter was mobil 1 & synthetic, oil since +/- 2004 oil changes I have added 1 quart of lucas, balance mobil 1 oil & filter, runs awesome, just drove it to alaska and put 10,000 miles on it in a month. toyota shop loves the rig, its dry, engine always detailed, used Fluid film for last 13 years to keep corrosion at bay.
2. Have a 1970 FJ40, 3 speed, +/- 90k original miles, runs awesome
3. Have a 1976 FJ40, 4 speed, +/- 96k original miles, de-smogged, engine had to be rebuilt after failed Holley carb swap poured gas down a couple cylinders, now runs awesome

4. Now the 92' saga, bought on ebay, spent $4k to service, rebuild trans, etc at 294k miles.......it was the tank that my 2 boys safely drove in high school and younger drove in college for 4 years. It now has 356k miles and needs some love. Sorry Im nostalgic. did a 4" OME lift, original rims and biggest BFG KO2's that would fit on a 15" rim.

The engine starts great even in subzero winter temps, engine runs great, idles great, no stalling, no backfires, no quitting which gets me past nearly all the troubleshooting pages in the repair manual. After reading through the entire repair manual I dont know what I'm missing. The exhaust pipes are ceramic coated & wrapped with fiberglass, valve cover & many other engine compartment parts have been powder coated last fall to enhance the rebuild. New hoses for radiator, heating, power steering, etc....

I'm at the end of my rope with resolving these codes. I have replaced the fuel injectors, caps, o-rings, fuel press valve, new fuel filter, new radiator cap, new radiator, & fan blade & Shroud, rebuilt power steering pump, replaced all the thermostat temp sensors, thermostat, replaced #2 VSV, new vacuum modulator, swapped out the EGR valve with clean one(may or may not work), installed new vac/air tubing with new spring clips, used specter off-road BVSV valve, etc......over the last 3-4 months and +/- $2000 in parts. The local repair shops look at it and say they can't help to save my sanity.

Installing and verifying that all the vac tubing/routing was correct from carelessness of shops over 32 years of service took time and found the P & R tubes had been reversed for a long time + resolved other issues. using caps and an air compressor was the savior to properly ID all the steel tubing passages without having the remove the intake plenum, etc....

Engine runs strong, trans/xfer case/axles good, body/interior good. Have been running lucas engine oil treatment, 3 quarts per change with mobil 1 filters......engine is dry

I have gone through the toyota repair manual and tested parts where needed, could it be the fuel cap or fusible link? those are the only old parts left on the rig!!!

Any help would be greatly appreciated.

 

[jonheld]

For error codes 25 and 26 I'd be looking at O2 sensors.
71 is all about the EGR system.
Tests for this stuff is all in the FSM.

 

[boobaa]

For error codes 25 and 26 I'd be looking at O2 sensors.
71 is all about the EGR system.
Tests for this stuff is all in the FSM.

many thx.....yesterday I installed a new fusible link and then test drove and rig ran super at 65+ mph for 40 miles, total time about an hour, then coming home driving through town the check engine light came on throwing the same errors.

I installed (2) new Ox sensors last summer when i installed the ceramic coated exhaust pipes so they should be ok. today I ran the Ox sensor test spelled out in the FSM for 25/26 called out on page FI-27. the check engine light did not come on after running the test 2x's.

Therefore I'm wondering if its an injector problem? I put in (6) new beck-arnley injectors from rock auto. Unfortunately I did not check the resistance of each one before I installed them. Its been cold in michigan so time outside is somewhat limited. I also checked the cold start injector and it checked out between 3.9-4.0 ohms per FI-56. I also pulled the EFI main relay and checked it per FI-79 and the continuities are correct. Also checked the ISC - idle speed control per FI-76 and its continuity is ok.

Tommorow Im going to do the driving tests per FI-28 to test if the injectors are the cause of the 25/26 codes and FI-29 for the 71 code.

Checked the diagnosis circuit per FI-30 and its system normal.

I haven't done any of the electrical checks with the ECU. Its hard to believe the yota folks put the ECU behind the glove box!!!! makes it tough to get the voltmeter tips in the right holes, tough to get "man hands" in the space without taking the dash apart!

 

[jonheld]

many thx.....yesterday I installed a new fusible link and then test drove and rig ran super at 65+ mph for 40 miles, total time about an hour, then coming home driving through town the check engine light came on throwing the same errors.

I installed (2) new Ox sensors last summer when i installed the ceramic coated exhaust pipes so they should be ok. today I ran the Ox sensor test spelled out in the FSM for 25/26 called out on page FI-27. the check engine light did not come on after running the test 2x's.

Therefore I'm wondering if its an injector problem? I put in (6) new beck-arnley injectors from rock auto. Unfortunately I did not check the resistance of each one before I installed them. Its been cold in michigan so time outside is somewhat limited. I also checked the cold start injector and it checked out between 3.9-4.0 ohms per FI-56. I also pulled the EFI main relay and checked it per FI-79 and the continuities are correct. Also checked the ISC - idle speed control per FI-76 and its continuity is ok.

Tommorow Im going to do the driving tests per FI-28 to test if the injectors are the cause of the 25/26 codes and FI-29 for the 71 code.

Checked the diagnosis circuit per FI-30 and its system normal.

I haven't done any of the electrical checks with the ECU. Its hard to believe the yota folks put the ECU behind the glove box!!!! makes it tough to get the voltmeter tips in the right holes, tough to get "man hands" in the space without taking the dash apart!

Couple of thoughts here.
When you installed a new set of fusible links, you cleared the codes that were stored in the ECU simply by removing constant +12. If one or more of the fusible links were faulty, you would have had other problems. Look at the POWER SOURCE section of the EWD starting on page 30. This shows you what each fusible link feeds.

It is a good practice to reset the ECU when you do any work under the hood. Simply removing the 15 amp EFI fuse in the relay box on the left fender for a few minutes is all it takes, and is less invasive than removing battery terminals.

You said you did the tests for the O2 sensors, but didn't say if they were in spec according to the FSM. There are also tests for the AFM that you should be doing.

If the EFI relay or associated logic was faulty, this engine wouldn't run.

Why would you use aftermarket injectors when you could have had your OEM injectors cleaned, balanced, and flow tested by several reputable companies that specialize in this? Don't use aftermarket parts in this engine, especially ignition components. It'll just spit them out and you'll wind up doing things twice.

Keep in mind that this is first generation EFI designed in 1986. All mechanical adjustments must be done according to FSM specifications first as the ECU has a very limited window of correction. Essentially, the 3FE is a fuel injected tractor motor. There's no magic in there.

 

[boobaa]

Couple of thoughts here.
When you installed a new set of fusible links, you cleared the codes that were stored in the ECU simply by removing constant +12. If one or more of the fusible links were faulty, you would have had other problems. Look at the POWER SOURCE section of the EWD starting on page 30. This shows you what each fusible link feeds.

It is a good practice to reset the ECU when you do any work under the hood. Simply removing the 15 amp EFI fuse in the relay box on the left fender for a few minutes is all it takes, and is less invasive than removing battery terminals.

You said you did the tests for the O2 sensors, but didn't say if they were in spec according to the FSM. There are also tests for the AFM that you should be doing.

If the EFI relay or associated logic was faulty, this engine wouldn't run.

Why would you use aftermarket injectors when you could have had your OEM injectors cleaned, balanced, and flow tested by several reputable companies that specialize in this? Don't use aftermarket parts in this engine, especially ignition components. It'll just spit them out and you'll wind up doing things twice.

Keep in mind that this is first generation EFI designed in 1986. All mechanical adjustments must be done according to FSM specifications first as the ECU has a very limited window of correction. Essentially, the 3FE is a fuel injected tractor motor. There's no magic in there.

many thx fr the detail.........I bought the aftermarket injectors because i was in a hurry and needed a solution. i agree with your thoughts.

Yes I cleared the codes after installing the fusible links. I agree removing the EFI fuse is the way.......the engine runs great after pulling the fuse until it gets warm driving around town or on the highway.

I found the VCV valve was bad and cannot find a new replacement. I am looking for a good used one. any thoughts where I can buy a new VCV? The new dense oxygen sensors arrived yesterday and i checked the new ones and they checked ok at 6.1 ohms. I also found my hose from the pvc valve to the intake plenum was slightly collapsed and needed to replace. This didn't solve the problem.

What's AFM?

Yes I have been resetting the egr by removing the fuse and also disconnecting the negative battery terminal.

The 71 error codes comes first which may be related to the bad VCV.

Forgot to mention I have replaced all the vac tube lines with heavy wall silicone tubing to minimize collapse issues.

I also replaced the distributor cap and rotor. the recently replaced ones still looked ok......

Many thx for your interest and followup......I really want to get to the end of this asap.

 

[ppc]

What's AFM?

AFM = Air Flow Meter

 

[jonheld]

What's AFM?

Yes I have been resetting the egr by removing the fuse and also disconnecting the negative battery terminal.

As stated, air flow meter. There are tests in the Toyota factory service manual (FSM).
The EGR can't be "reset". You can only clear error codes that get stored in the ECU when you remove power from the ECU by disconnecting a battery terminal or removing the 15 amp EFI fuse.