The 3rd Gen All Questions Allowed Thread

[RogueWaive]

Yes, it is an AFR sensor. Looks externally like a normal O2 sensor, but it is more advanced. Not quite a modern full wideband sensor, but it works pretty well. Replacing both the front AFR and rear O2 sensors should be part of chasing down P0420 problems... Even if it just to save the new cats you might have to install.

There will be a number of OEM part numbers - they are different RWD vs. 4WD and CA vs. Fed emissions (and then there are 4-cylinder options in there...). RWD vs. 4WD are clip locations (nothing serious), but the CA vs. Fed front sensor is critical.

-Charlie

OK, called and spoke with my service agent at the stealer. He's been our guy since the '80s. He sent me to his preferred parts guy. I told him the situation. Also mentioned that you said it should be an AFR. He said that sounded right to him, as well. As on the Denso site, he found 4 upstream (front) possibilities. But based on the Cali designation, he narrowed it down to the 234-9002. Sure enough. This is an AFR.

The downstream he gave me is the 234-4153, which also makes sense. That's the Cali version of the one the other guy gave me yesterday. I'm guessing the only difference here is the length of the pigtail.

Looks like we solved it. So glad I didn't simply accept those part numbers.

Thanks again!

 

[aatheiss]

Yes, it is an AFR sensor. Looks externally like a normal O2 sensor, but it is more advanced. Not quite a modern full wideband sensor, but it works pretty well. Replacing both the front AFR and rear O2 sensors should be part of chasing down P0420 problems... Even if it just to save the new cats you might have to install.

There will be a number of OEM part numbers - they are different RWD vs. 4WD and CA vs. Fed emissions (and then there are 4-cylinder options in there...). RWD vs. 4WD are clip locations (nothing serious), but the CA vs. Fed front sensor is critical.

-Charlie

[MENTION=139000]phattyduck[/MENTION] sounds like you have done some research on these so I'm hoping I can get your thoughts on my specific case.

I have a 4-cyl Hilux Surf, the upstream sensor is an O2 (89465-39835), I figure I can replace that with little difficulty. However, it has an EGT sensor (89425-80033) on the downstream, plugged into the back of the cat itself instead of an O2 sensor a little farther down in the pipe. The EGT sensor is discontinued and not available anywhere I can find. My guess is they are not interchangeable, but I'm hoping I can find an alternative when I inevitably need to replace it or my cat. Am I correct in assuming there would be a different signal or voltage being sent to the control module if I tried an O2 sensor?

 

[phattyduck]

so I'm having an issue with my power locks. whenever it rains or the car gets wet, the locks seem to actuate-themselves. when im driving or when its sitting, the car will lock and unlock itself, setting off the horn alarm.

everything I found is related to door actuators themselves, etc. however this only happens when the car gets wet. any thoughts?

Assuming you have a 99-02? If so, the rear hatch has the wireless receiver in it and may be having moisture issues.

The other possibility is the front - how is the large grommet where the wiring from the engine bay fuse box enters the body? (above the driver's dead pedal) Water flows over that when the truck gets wet and it MUST be sealed well.

-Charlie

 

[phattyduck]

[MENTION=139000]phattyduck[/MENTION] sounds like you have done some research on these so I'm hoping I can get your thoughts on my specific case.

I have a 4-cyl Hilux Surf, the upstream sensor is an O2 (89465-39835), I figure I can replace that with little difficulty. However, it has an EGT sensor (89425-80033) on the downstream, plugged into the back of the cat itself instead of an O2 sensor a little farther down in the pipe. The EGT sensor is discontinued and not available anywhere I can find. My guess is they are not interchangeable, but I'm hoping I can find an alternative when I inevitably need to replace it or my cat. Am I correct in assuming there would be a different signal or voltage being sent to the control module if I tried an O2 sensor?

The EGT sensor is likely only connected to an idiot light on your dash... that's how Toyota did a lot of the non-North-American vehicles. Basically just closes a switch to ground when the EGTs are too high. To verify, you'll need to get a wiring diagram for your vehicle (the US/Canada diagram won't have it).

That's how my 3s-gte was done. I just deleted that feature (along with the cat in that location, but that's a different story!).

-Charlie

 

[mpeezy]

Assuming you have a 99-02? If so, the rear hatch has the wireless receiver in it and may be having moisture issues.

The other possibility is the front - how is the large grommet where the wiring from the engine bay fuse box enters the body? (above the driver's dead pedal) Water flows over that when the truck gets wet and it MUST be sealed well.

-Charlie

thanks for this - will see if i can trigger it with the hose, didn''t know about the receiver in the hatch. cheers

 

[Mimck]

4wd Light Blinking in 2WD

New here, but having issues with my 4x4 light on my 2002 4Runner SR5. The car shifts into 4wd seemingly fine and the light will turn on green with all 4 wheels. However, sometimes the light flashes in the car when I’m in 2wd. Not only does it blink, but it also will be glitchy and sporadically blink as well. It usually doesn’t happen until I’m going highway speeds and take my foot off the accelerator/brake. It usually will stop after a while, but when I hit a bump or go over a bridge it will flash for a second. It almost seems like a loose connection somewhere, but I can’t figure out why it is so random.

Let me know what anyone thinks- not sure where to go from here.

 

[thisMF]

96 4runner 3.4 5vzfe running rough 230000 miles.

Afternoon, I bought it a week ago knowing it was gonna need some $ in it. Ran great for 500miles. Now it idles around 500rpm runs rough like a misfire and sounds like it backfires (may not be backfiring) if I accelerate lightly. Thermal sensor shows a cold #4 cylinder. I got plugs, wires, coils, fuel filter, I intend to pick up a MAF, a IACV and a pcv valve. Does it sound like I'm on the right track. I've looked up and down threads and this is the direction I gather I should head in. Also will be looking at injectors. Any thoughts tips and tricks?

 

[phattyduck]

Afternoon, I bought it a week ago knowing it was gonna need some $ in it. Ran great for 500miles. Now it idles around 500rpm runs rough like a misfire and sounds like it backfires (may not be backfiring) if I accelerate lightly. Thermal sensor shows a cold #4 cylinder. I got plugs, wires, coils, fuel filter, I intend to pick up a MAF, a IACV and a pcv valve. Does it sound like I'm on the right track. I've looked up and down threads and this is the direction I gather I should head in. Also will be looking at injectors. Any thoughts tips and tricks?

Make sure the parts you are putting on are quality stuff. Plugs/wires/coils - NGK or Denso. MAF and IAC should be cleaned before trying to replace (early MAF is EXPENSIVE!). Easy enough to check the PCV before replacing. Get a new grommet and hose if you are doing that.

A "hollow" or "backfire" type feeling is likely a misfire, any check-engine light?

-Charlie

 

[thisMF]

Make sure the parts you are putting on are quality stuff. Plugs/wires/coils - NGK or Denso. MAF and IAC should be cleaned before trying to replace (early MAF is EXPENSIVE!). Easy enough to check the PCV before replacing. Get a new grommet and hose if you are doing that.

A "hollow" or "backfire" type feeling is likely a misfire, any check-engine light?

-Charlie

It was on since I had purchased it. Code is for wheel speed sensor. Previous owner stated it has been replaced. And had always been on since they had it.

The parts I already purchased were intermotor from Bumper to Bumper.

No code as to rough running. Will scan again when I get home. Gonna stop and get my own obd2 any recommendations as to which ones work best?

 

[mpeezy]

Most of the time the squeak is the entire stroke, but occasionally it's the bottom or top half. I removed the spring to make sure that wasn't causing issues. My next step is to remove the master cylinder and see if the squeak is still present.

circling back -- replacing my master cylinder fixed the issue

 

[NoahJTN]

1998 Limited, I know these fog lights were allegedly a “dealer option” and aren’t available anymore but had heard there were some nearly identical aftermarket replacements. Does anyone have a link or item number?

 

[phattyduck]

1998 Limited, I know these fog lights were allegedly a “dealer option” and aren’t available anymore but had heard there were some nearly identical aftermarket replacements. Does anyone have a link or item number?

I'd start with a Hella rectangular fogs (450? 550?) and see if the measurements work. They are the right style, if not exactly the same size.

-Charlie

 

[JoeT4R]

I may or may not need to replace my battery by the end of the week. Went to fire up the truck today and that sucker was dead. Hooked up jumper cables from my other vehicle to the truck and nothing. Pulled the battery, have it sitting on a trickle charger outside currently. Will wait for it to reach a full charge.

But if that doesn't work, I'll be getting another battery from Costco again. My question is, AGM or standard lead acid? I've never used an AGM before but can see the benefits. Let me know.

 

[Spiker Engineering]

But if that doesn't work, I'll be getting another battery from Costco again. My question is, AGM or standard lead acid? I've never used an AGM before but can see the benefits. Let me know.

I don't have an answer, but will be following with great interest as I'm also pondering AGM vs FLA. I'm tired of corrosion of FLA - even though I fully coat the terminals with corrosion preventative paste, my two year old OEM battery holddown is all corroded again. So I'm leaning to AGM, but am hung up on the higher charging voltage requirements that I keep reading about.

 

[phattyduck]

I don't have an answer, but will be following with great interest as I'm also pondering AGM vs FLA. I'm tired of corrosion of FLA - even though I fully coat the terminals with corrosion preventative paste, my two year old OEM battery holddown is all corroded again. So I'm leaning to AGM, but am hung up on the higher charging voltage requirements that I keep reading about.

I have taken to spraying all my 12V battery terminals with a squirt of Fluid Film every time I mess with them - on all my vehicles that have standard FLA batteries. Same for the now only half painted battery hold-down on the 4Runner.

-Charlie

 

[Bad Luck]

circling back -- replacing my master cylinder fixed the issue

I might give that a try again next year. It's strange that I had the same squeak before and after replacing my master cylinder with an Aisin one. What brand did you go with?

 

[Endlessblockades]

The only AGM downside I can think of is cost.

 

[JoeT4R]

The only AGM downside I can think of is cost.

Thanks for the feedback brother. What's with all this "yOu HaVe tO cHaRgE iT" b.s.? Im assuming it works somewhat differently, at least internally, compared to your standard battery but some people are saying they require special chargers and such.

 

[RogueWaive]

The only AGM downside I can think of is cost.

Well there IS one more, though not typically super important for starting batteries.

Hardened sulfate can be broken up by equalizing flooded batteries. Equalizing AGMs can be very tricky... and dangerous.

They are good for rough and tumble 4-wheelin'.

So long as you keep them topped 24/7, 365, they can be great and last a long time.

 

[Spiker Engineering]

What's with all this "yOu HaVe tO cHaRgE iT" b.s.? Im assuming it works somewhat differently, at least internally, compared to your standard battery but some people are saying they require special chargers and such.

I'm no battery expert, but from my research it looks like AGM batteries require about 14.4-14.8V to charge properly. That's a lot more than the 4Runner alternator can provide.

Some folks have used modules to bump the alternator output to the higher voltage. The one downside to that is that some components in the truck (e.g. light bulbs) may not be designed to operate at the higher voltage.

Other folks follow the strategy of using a charger to occasionally charge the battery fully, since chargers can provide higher voltage. That seems reasonable, but is one more thing to keep in mind.

Yet others have said that they've ran the AGM battery as is, with no issues. Though the counterargument seems to be that by doing that, the life of the battery will be shortened significantly.

So, it's not as simple as it seems . I'd still love to get an AGM for my next battery, just want to make sure I know what I'm signing up for.