O2 Sensor - OEM vs Denso? (1 Viewer)

[Qball]

They have different plug connectors, so they can only go in one, hard to screw up when they make it easy for a change.

Awesome, thanks!

 

[mypancreasbroke]

Hhmmm, wish I had my old o2's to try and clean them... I replaced with Bosch plane styled sensors after reading a long thread here on mud. I immediately noticed better mpg, slightly lower highway rpms, and my CEL disappeared, but since the install have a weird almost stall like hesitation when first accelerating after my truck has sat and is cold. Doesn't matter what gear I try to accelerate in, or if I leave straight from start or letting the truck completely warm up, still have a weird hesitation. That being said, did a quick search online and just ended up impulse buying these off eBay

http://m.ebay.com/itm/290836724529?nav=SEARCH

Brand new Denso 234-4520 sensors for $69.95 with free shipping. Only a few left if any of you 93-94 guys want to save some $$$.

 

[Qball]

Just replaced the factory sensors with about 200k with denso sensor from amazon. The original ones look pretty good for been in service for 17 years and 200k. Mine is a 97 and the sensors doe say toyota and Denso on them. The new sensors are smaller so I hope they've improved the design and therefore they are smaller. Either way I'm keeping the old ones as spare.

Since the rig has been SoCal all its life I had no issues with rusted on nuts. It literally took me longer to unplug the after cat sensor then Unbolting both sensors.

 

[Qball]

Just took a quick drive and immediate noticed more pep/power. Also noticed my idle rpm is quite a bit lower. With gears engaged my rpm dropped from 650 to 610, and when in neutral rpm dropped from 690 rpm to 640. This is one maintenance item I should of done long ago!

I wonder why this is the case. Maybe the new sensors are more sensitive to oxygen and detects more oxygen, the ECU added more fuel so it's not as lean? Not sure if that explains the lower idle rpm. Think I'll disconnect the battery tomorrow to form the ECU to relearn and see if the idle and extra pep stays.

 

[mypancreasbroke]

OBD2 sure seems nice. My new sensors arrive today and I'm hoping for some time to install... Though my trucks outside, it's below freezing, good layer of ice, and the garage is occupied so we'll see what happens. I am interested to see though if my hesitation issue is fixed.


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[mypancreasbroke]

Quick and easy install and my hesitation issue is gone. Glad I pulled the trigger and went back to OEM. Still a few left on eBay at that good price for any 93-94 guys who may need them.


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[yellowgeko]

same sensor part number?

Hhmmm, wish I had my old o2's to try and clean them... I replaced with Bosch plane styled sensors after reading a long thread here on mud. I immediately noticed better mpg, slightly lower highway rpms, and my CEL disappeared, but since the install have a weird almost stall like hesitation when first accelerating after my truck has sat and is cold. Doesn't matter what gear I try to accelerate in, or if I leave straight from start or letting the truck completely warm up, still have a weird hesitation. That being said, did a quick search online and just ended up impulse buying these off eBay

http://m.ebay.com/itm/290836724529?nav=SEARCH

Brand new Denso 234-4520 sensors for $69.95 with free shipping. Only a few left if any of you 93-94 guys want to save some $$$.

I have a 94 as well and need to replace my sensors. If these are the right ones I am going to pull the trigger. For the 94, are both sensors the same part number? I thought I read earlier that they where two different part numbers for each one.

 

[Kernal]

IIRC the earlier year FZJ's had NTK/NGK O2 sensors as OEM, don't know if it makes a difference??

 

[musthave]

Seeing this thread reminded me, I need to get new 02 sensors this week.

 

[mypancreasbroke]

I have a 94 as well and need to replace my sensors. If these are the right ones I am going to pull the trigger. For the 94, are both sensors the same part number? I thought I read earlier that they where two different part numbers for each one.

Installed and they're working perfect. Same part number as they're are the same sensor, just takes two of them. Luckily not much rust on my truck so it was quick and easy install.


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[mypancreasbroke]

IIRC the earlier year FZJ's had NTK/NGK O2 sensors as OEM, don't know if it makes a difference??

I didn't take pics or look too closely, but while installing remember seeing 'NTK' and 'JAPAN' stamped into them. I'll try to go get another look soon and grab a pic.


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[yellowgeko]

Installed and they're working perfect. Same part number as they're are the same sensor, just takes two of them. Luckily not much rust on my truck so it was quick and easy install.


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That is just what I was looking for! Thanks!

 

[mypancreasbroke]

Got a quick pic. 'NGK' looks to be stamped on them.


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[tlin]

Any reason NOT to try to clean my O2 sensors? I've got new Slee O2 bungs being delivered now, would like to see if cleaning the existing sensors does me any good before those arrive and that pipe/bungs ahead of my cats also gets replaced.

Truck's in overall very good condition '92 with ~144K on it, runs strong (3FE strong). "ain't broke don't fix it" or just get under there and clean 'em??

thx...

 

[scrowley]

I just got some denso's from rock auuto. Going to install tomorrow. My 1.5 yr old slee bung studs look pretty ruff already. Damn ct winters. I even coated it with high temp never seize. Didn't do much.

 

[JimGeorgia]

Here's another Denso vs Bosch story. So I got the the dreaded 420 code while trying to pass emmissions here in communist Atlanta. The error code actually reads, P0420 Catalyst Sys Efficiency Below Threshold. There are several troubleshooting steps on the MUD Forum before you get to my next step which was to replace the catalytic converters. I ordered OEM from Advance Auto for $719 plus shipping. FYI - I have a 96 LC with two in-line cats. I liked Advance Auto because they also had O2 sensors, sort of a one stop shop. Or so I thought. Without thinking or reading much on MUD I ordered Bosch sensors (part no 13422 upstream @$110 and part no 13136 for downstream @$90). After having my emmsions shop clear the error codes and then resetting the computer (drive 15 miles at 55-60 mph, immediately followed by stop-and-go traffic for about 15 mins), I had the system re-tested. The 420 error code was now gone, but the test failed. This time the error code was caused by an O2 sensor "heater". I didnt know what that meant but it was coming from the upstream Bosch sensor. So I go back to Advance Auto and order a replacement. I reinstall the replacement BOSCH sensor, have the error code reset, and drive the truck to reset the computer. I take it back for an emissions test and GET THE SAME [omit word] ERROR code coming from the Bosch [omit word] sensor. So I finally read the MUD forum, get smart and order DENSO sensors. Advance Auto tells me they are out of stock but I found them on Amazon via StockWiseAuto - Denso Part No. 234-4156 upstream $64 and Denso Part No. 234-4153 downstream @$62. Then the same drill - reset codes, drive to reset computer and retest. This time PASS! So the morals of this story are: 1) only buy Denso, 2) shop on Amazon and pay about 50% the cost of big box auto parts stores and 25% of the dealership's parts prices, and 3) you can install cats and senors in 2 to 3 hours in your driveway. Its a 2 banana job and all you need are metric wrenches and WD-40). Oh, one more moral: 4) BOSCH is crappolo.

Also, there ahve been several questions on MUD about which way to install the sensor gasket. See photo attached and how it comes fitted in the sensor from DENSO.

 

[carbon60]

For the people searching: WRONG 234-4156 WRONG.

Denso Part No. 234-4156 upstream $64 and Denso Part No. 234-4153 downstream @$62.

I thought I should bump this thread because, from my research and testing, the correct upstream Denso O2 sensor is 234-4157.

I had the wrong one in my truck and still suffered intermittent codes. Putting the correct one corrected these. Plus, the lead on the correct one is a little shorter, thus preventing it from flapping around.

A.

 

[96Cruiser]

For the people searching: WRONG 234-4156 WRONG.



I thought I should bump this thread because, from my research and testing, the correct upstream Denso O2 sensor is 234-4157.

I had the wrong one in my truck and still suffered intermittent codes. Putting the correct one corrected these. Plus, the lead on the correct one is a little shorter, thus preventing it from flapping around.

A.

this is correct, I just installed 234-4157 pre cat and 234-4153 post cat Denso sensors, bought last year from partsgeek, got lucky I guess, right parts showed up cheap and when finally installed corrected my p0171 and p0125cel's, hopefully I will see improved gas mileage as well.

 

[socallove]

The million dollar question? Replace ($$$) or Clean your O2 sensor .

Replace the oxygen sensor only if it's bad. They do wear out and the FSM, Chilton's or Hayne's manual for your car should have directions on how to test it.

An OEM replacement sensor for some popular cars is about $240, and your car probably has two of them. If you replace it with a cheap sensor from a discount parts store, you may be throwing away a perfectly good high quality sensor which just needs to be cleaned.

Here's a quote from a Toyota mechanic with 32 years of experience, on another web site:
"You don't need to replace them, remove them and clean them. [If you read an O2 sensor malfunction code] The computer is saying the vehicle is running a little rich or lean. IT DOES NOT mean the sensor(s) are bad. Auto parts stores just want to sell you products. If I received a dollar every time a 02 sensor was replaced on a vehicle I'd have millions."

That said, there doesn't seem to be an "official" way to do it, or an entirely safe way. But since you ask, here are some ways people have done it:

1. Clean it with a throttle body aerosol cleaner which states that it's safe for oxygen sensors.
2. Heat it up with a torch and dip it in water. Use an air hose to clean the gunk out. Repeat.
3. Soak it in "Seafoam" (the engine cleaner, not salt water) overnight.
4. Soak it in gasoline overnight. Shake the dissolved gunk out.

It's one of those things, like nobody's going to tell you how to clean your bathroom mirror with ammonia at $0.99 a gallon, but lots of people are happy to sell you ammonia with blue die in it at $4.50 a pint.

Just want to share my experience, maybe it can save some folks $100. I had a cel so ran the scan gauge and got the egr code P402. A good friend told me to replace the egr solenoid so I procrastinated for a few months and finally bought an oem, then procrastinate a few more months before putting it in bc it was some what of a pita but I'm glad I got it done. CEL went away so I drove to his house to use his odb2 diagnostic tool and check timing. Diagnostic showed I had some issues with the O2 sensors, he let me borrowed the scanner and off I went. Order Denso O2 sensors from Amazon for $100, popped the old ones out and put new sensor in. Went into the garage and decided to test out the cleaning method that was posted. I used a creme brûlée torch and heated up the sensors until they were red, dunked it in a jar of distilled water and the debris started falling off. I was fascinated so I heated them up and dunked them four times each bc I keep seeing debris falling. Brushed it with a wire brush each time for the stubborn stuff and went up stairs. I was curious if the clean sensors will function again, so I ran down and popped the denso out and put the original back in. I got discouraged after driving around for 25 minutes with the diagnostic tool plugged in and still beeping at the error, but I was thinking, "as soon as give up and go home, it will magically clear the code." So I went home and pulled up to my parking spot, the light turned green and the code stopped flashing. I'm keeping the denso O2 sensors so I can loose it in the garage and go crazy if I need it in two years.

Picture shows a dirty sensor on the right and the once heated and dunked on the left. Debris at the bottom on the glass jar.

 

[jtwopark]

glad it worked out! did you use the toothpaste method i told you about? lol