P0172 code

[Dezerts10]

I’ve been reading some stuff this morning and can not get a grasp on where to start.

I threw a p0172 code a few weeks ago towing my camping trailer up a grade high rpm about 70 miles into my trip reset it with my scanguage and it didn’t throw a code the trip or drive home. I parked the 4Runner and the last few days been driving to work and threw the code again today idling at a stop light.

Not incredibly worried as it’s a rich first bank code and that doesn’t seem like it would really cause much beside maybe a fuel mileage issue but I want to figure it out and fix it.

Any suggestions on where to start? 207k miles unknown maintenance record. I’ve done stuff since I got it that is routine but not sure if sensors were ever replaced or anything like that.

Thanks


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[sakoluvr]

Did you try cleaning your MAF sensor? I would start there because it is cheap and easy to do.

 

[Dezerts10]

i have not done anything besides clear the first code with my scanguage the first time it happened.

I was going to start with air filter, clean the MAF, maybe even O2 sensors if they are semi affordable, ill run some injector cleaner as well the next few tanks of fuel as well but doing reading it seems like these types of tasks really wont solve the problem.

I guess im looking for suggestions on what a more serious issue might cause a P0172 code

 

[sakoluvr]

I think the MAF is a common cause.

 

[Dezerts10]

guess ill start there and hope for the best.

 

[gamefreakgc]

i have not done anything besides clear the first code with my scanguage the first time it happened.

I was going to start with air filter, clean the MAF, maybe even O2 sensors if they are semi affordable, ill run some injector cleaner as well the next few tanks of fuel as well but doing reading it seems like these types of tasks really wont solve the problem.

I guess im looking for suggestions on what a more serious issue might cause a P0172 code

Worst case is a bad injector putting in too much fuel but start with the cheap & easy stuff first like you listed.

 

[Dezerts10]

Well that came out of the air filter when I dropped it face first on the ground and this is what the inside of my air box looked like after sucking some dirt outa it with a vacuum

Why would I be getting so much mud in the airbox?

Also, just curious what are these chambers for on the stock intake tube

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[firemanj92]

Well that came out of the air filter when I dropped it face first on the ground and this is what the inside of my air box looked like after sucking some dirt outa it with a vacuum

Why would I be getting so much mud in the airbox?

Also, just curious what are these chambers for on the stock intake tube

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Chambers on intake tube are for noise cancellation/resonators. Looks like the T4R has been in some muddy/dirt water/environment.

 

[Dezerts10]

Chambers on intake tube are for noise cancellation/resonators. Looks like the T4R has been in some muddy/dirt water/environment.

Yes, it has. I guess I was more asking why so much gets into the the airbox like would that amount be a result of an issue with the intake system or is that normal picked up from the fender intake tube.

I want to do a snorkel eventually too and this is reason enough if that is “normal”

Behind the filter the intake tube was clean though so the filter works


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[Dezerts10]

Well the P0172 code came back up this morning driving to work.

I didn’t reset it yet but it had been off for months, had the 4Runner smog checked about 6 or so weeks ago and have been driving it to and from work this week. but not much the last month as I was working on the panhard bar

Guess it’s back to the drawing board as to what’s going on.

O2 sensors may be next on the list to replace.


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[Dezerts10]

Well the P0172 code came back up this morning driving to work.



I didn’t reset it yet but it had been off for months, had the 4Runner smog checked about 6 or so weeks ago and have been driving it to and from work this week. but not much the last month as I was working on the panhard bar



Guess it’s back to the drawing board as to what’s going on.



O2 sensors may be next on the list to replace.





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Guess it’s time to put in O2 sensors. Light came on again this morning. Can anyone help with a link or part number for a 1996 3.4l o2 sensors.

I’ve read a few things about California models? How do i know what I have?

Thanks


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[TheDurk]

Guess it’s time to put in O2 sensors. Light came on again this morning. Can anyone help with a link or part number for a 1996 3.4l o2 sensors.

I’ve read a few things about California models? How do i know what I have?

Thanks


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No Cali in 1996. You're Federal.

Get the Denso P/N here:

DENSO Auto Parts

depends on trans, drivetrain as well as engine.

Then buy it on Amazon or Rockauto or wherever is cheapest.

 

[Dezerts10]

Upstream I assume means near exhaust manifold, down stream is down by cat, correct?

The universal denso sensors reviews on amazon say I’ll need to splice in factory plug. I don’t want to do this I’m a horrible at soldering.

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[tvpierce]

Did you clean the MAF Sensor?

EDIT: and if you did... are you sure you actually got the MAF Sensor, and not just the Temp Sensor bulb? (see pics)

http://www.toyota-4runner.org/3rd-gen-t4rs/86675-help-p0171-3.html

 

[Dezerts10]

i did in February when it threw the code first. plus changed air filter

 

[jgue467]

First don't get "universal" get OEM.

Second, Check the Denso site first, don't rely on Amazon or ebay to get the right part for your MY.

Double check me folks but on the Denso site I see for a 96 3.4 the following:

downstream 234-4153 (2wd) and 234-4154 (4wd auto trans)

upstream 234-4162 for both 2/4 wd Auto trans. Check site if ya' got a manual Luck. :cowboy:

 

[Dezerts10]

picture above is from denso site. I put in denso numbers in amazon and read reviews and saw the plug splice issues

denso pricing was same on their site and on amazon.

Weird thing is I went to the URD website referenced in another oxygen sensor post and none of the part numbers I found were on their site for Denso oxygen sensors.

 

[gamefreakgc]

picture above is from denso site. I put in denso numbers in amazon and read reviews and saw the plug splice issues

denso pricing was same on their site and on amazon.

Weird thing is I went to the URD website referenced in another oxygen sensor post and none of the part numbers I found were on their site for Denso oxygen sensors.

I think you are confusing yourself by looking in too many places.

234-4162 for upstream sensor for your year and auto transmission.

234-4161 for upstream sensor for your year and manual transmission.

Those part #'s are not universal, they are plug and play for your year.

 

[TheDurk]

Upstream I assume means near exhaust manifold, down stream is down by cat, correct?

The universal denso sensors reviews on amazon say I’ll need to splice in factory plug. I don’t want to do this I’m a horrible at soldering.

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Yes, upstream closer to engine. Don't get the universal, get the direct fit. Don't use Amazon for p/n. Get the p/n from Denso for direct fit, THEN go buy that p/n from Amazon, just like I said in my first post.

 

[Dezerts10]

Yes, upstream closer to engine. Don't get the universal, get the direct fit. Don't use Amazon for p/n. Get the p/n from Denso for direct fit, THEN go buy that p/n from Amazon, just like I said in my first post.

that's what I did, I think you guys are misreading what I said.

I went to Denso website you linked found the three items from the picture, then went to amazon and looked up the universal sensor, read that I would need to splice in the stock plug then I asked my 2nd question.

But I did notice the denso and Amazon have the same priced basically.

Ill be buying the upstream and downstream sensors. not the universal sensor.