:clap: Hey, thank you for that write-up, something very rare for first time posters so it's very much appreciated! I'll move your thread over to the T100 forum, though, so it can help out the other owners there who may come up with the same issue.

Welcome aboard Toyota Nation...:hi:...I think you'll fit in well here.

 

Thanks much for moving it to the correct forum. I'll pay attention to that the next time.

 

Thanks for the write-up and welcome! :thumbsup: That's a heck of a first post. Hopefully we can return the favor as there is lots of great info for these trucks on this forum. Thanks again!

 

Thanks fer doing the in-depth leg work fer the rest of us 1997/98 5vzfe T-100 owners.

BTW...how did you test the sensor? What tools/equipment did you use to measure the readings? Got any piccies?

In this article over at Yotatech, the OP found out that the Sienna VPS would work as well.
http://www.yotatech.com/f166/p0441-p0446-p0450-p0451-251680/

This was my feeble attempt at dinking around with my sensor.
http://www.toyotanation.com/forum/60-t-100/355880-check-engine-code-450-451-a.html

BTW...that should be a P0450 and not a PO450. Zero not an "O'.

 

You wouldn't still happen to have yer old sensor? Is it possible fer you to take it apart and snap piccies of the guts? I'm curious on what's inside and what could've caused the issues. I'm guessing the vapors could've gummed up the sensor.

Thanks in advance!

 

Although I'm not smart enough to understand half of what you wrote in that first post I appreciate the half I could understand.:burnout:

Welcome aboard.

 

Bam:
Thanks for catching the "O" and "0". I fixed this.

Also, thanks for the other links; I reviewed them earlier this morning. It only makes sense that Toyota would leverage the engineering on the sensor, and use it (though perhaps in different mechanical shapes/mounts) on multiple vehicles. It is impossible that any car manufacturer re-engineers each vehicle from the "ground up" every year - impossible, unless they don't intend on staying in business.

On the old sensor and my method to test it and the used replacement: I'm in the middle of something now, but I'll post some pictures of my test rig and the testing process (probably during the weekend). It actually is pretty simple. And, yes, I have the old sensor. After examining it closely, it is evident that a "lid" (for the sake of a better term) is glued in place over the electronics. I'll take my Dremel to it to see what't inside, then post the pictures.

In the case of my broken sensor, it would hold neither vacuum or pressure. Apparently, it has a hole of some kind; it clearly was not the case of simply being clogged.

I think that the operating principle of these sensors is that there is a diaphragm (which is actually a strain gauge) that is part of what is called a Whetstone bridge. Small changes in pressure distort the diaphragm, which in turn changes the potential across the Whetstone bridge, which is then picked up by the ECM. I mention this only to emphasize that these sensors are *VERY* sensitive. The vacuum/pressure is literally only 0.3/0.25 PSI - blowing into it (like trying to clear it) would easily fracture the diaphragm.

Anyway, I'm very anxious to see what's inside - and why Toyota thinks it's worth $200!!

Okie-J: you're welcome!

 

Nice work! Now the important thing. Post up some pics of your t100.

Seriously great work and as you can tell this is a great place here.

 

On a somewhat related note, I fixed a snapped-off vacuum line fitting in the top of my evap valve. I drilled the hole out to a slightly larger oversize, then epoxied in a 3/4" long piece of brass tubing from the hardware store. With the vacuum line in place, you can't tell it was even fixed.

Be sure to take a shop vac and a piece of rubber hose, and suck all of the drill cuttings out of the hole before you seal it up.

Nice work!

Arclight

 

Wow, good work working the Toyota Man to just get enough info to figure this out. The following is a poor mans work around this problem if you can live with a hack job. I have a 97 T100 that just lost its Vapor Pressure sensor and could not find anything for it. My original 89460-0W020 was made by Delco but they have no info on that part number. I looked around the Delco site and found a part that looked quite similiar and found it online for Cheap ($13.50 with shipping), one of my requirements from my bull headed ness. This part is made for GM so of course the electrical connector does not quite fit and the vacuum port is made for an American size hose instead of metric. I am a former engineer and the specs you got from Toyota seemed loose so a similiar part would probably work. Hooked up the unit to a 5V power supply and a DVM on the output pin and took a couple of readings: 1.45V open air, 0.5V mild mouth blowing, 3-4V mild mouth sucking. So at least this part has the same rough slope as the Toyota part. Cut up my old sensor to salvage the connector and ground down the plastic on the new sensor vacuum port to fit my metric vacuum hose. Soldered wires across and potted them in epoxy back shells so they should hold up for a while. Installed the part, reset the codes and 500 miles later no new codes. Now to get it smogged. New OEM 12206740 Fuel Pump Tank Vapor Vent (EVAP) Pressure Sensor. HERKO INTERNATIONAL, INC. jcg@herko.com
150K on my truck and holding up well except had to reinforce the fire wall due to cracking the the clutch pedal support point. Regards Mark

 

I don't have a dog in this hunt, but thanks for that great post. Good ol legwork got you far and this looks very helpful!

 

Awesome, thanks for the great info! Please let us know if any issues pop up as the miles rack up.

 

Thanks for that info. Sometime you have to get pushy and you came through. This will no doubt help others. This is a great forum. welcome and thanks again.By the way where is this sensor and what does it do.

 

This is a pic BAM posted of his. I believe it's on or near the emissions canister.
From a discussion on the same subject some Time ago.
http://www.toyotanation.com/forum/60-t-100-forum/355880-check-engine-code-450-451-a.html

Pic:

 

I ended up gitting a used sensor from a 5vzfe engined Tundra and it seems to work just fine fer me. No issues fer over a year now.

The sensor is different on the outside but it works.

 

Your post worked for me. Many thanks. Vann Vaughan, Houston, Texas

 

I used part number 89460-35030 to replace the 89460-0W020. It is a Vapor Pressure Sensor for the Tacoma and 4Runner (late 1990’s). It took me a total of 10 minutes to install even with a minor modification. The photo in the 6-30-2015 post is a good representation of the original sensor. The new sensor comes with a bracket which is different than the original. However, the electrical connection stretches enough to connect correctly and so does the vacuum hose.
When the new sensor is bolted onto the T-100 it will sit up above the hood line. I had to bend the bracket on the T-100 down so that the sensor is below the hood line. The sensor bracket will not bend. I have driven the T-100 for about a month and the Check Engine light has not come on.

 

Late to the party but a similar story with my 01 Tacoma 2.7. Vapor pressure sensor is obsolete from Toyota and most aftermarkets. Toyota parts guy says its specific to 01-02 Tacos only - no other models used it. From a discussion on TacomaWorld, the SAME sensor was used on late 90's Camry and Lexus ES300. Different part number, same dimensions, same specs, SAME! Got one from a 98 ES300 from a wrecking yard for 4.50, plugs right in, no issues. Proprietary info/knowledge sucks!!

 

All:

This is my first post, and I want to use this opportunity to share how I finally solved the problem of the obsolete evaporative pressure sensor 89460-0W020.

I purchased a used '97 T100 in August 2013 with an inspection renewal a few months later (Dec 2013). Unknown to me, a previous owner had removed the engine check light from the dash. When I took the truck into the shop for inspection in mid-December, it failed because the engine check light did not come on briefly when the ignition was turned on. They looked further into the issue and found that the engine check light had been removed. They also found that the ECM reported a code of P0450 "Emission Control System Pressure Sensor Malfunction". Last of all, once they looked for a replacement for the sensor, they found that it was obsolete. (This, of course, is why a previous owner had removed the light.)

When the shop told me that the part was no longer available, I began a full-scale search for the part, pretty much coming up with dead-ends in the US. (I was entirely unwilling to spend $200+ to get a used part out of Japan or the UAE.)

I worked with the local DPS here in Texas, and they granted me a temporary waiver to give me time to find the part. Thank you Texas DPS!

Finally, after spending a lot of time at the parts counter at the local Toyota dealer, I found two really crucial pieces of information:

The first item was the actual diagnostic procedure to test the 89460-0W020 sensor: pull a vacuum of 8" water column (2.0 kPa), measure a voltage of 1.3V-2.1V; open the sensor to the ambient pressure, measure a voltage of 3.0V-3.6V; apply a pressure of 6" water column (1.5 kPa), measure a voltage of 4.2V-4.8V. I now had the information needed to validate a used part, if I could find one.

The second item - obtained only after pleading with the Toyota parts guy for more help - was to look up the same information on another model to determine whether a similar/identical part could be used. At first, he maintained that he had looked and found nothing. But, I wanted to see for myself and asked - specifically - to look at the equivalent sensor in a '97 Tacoma. Once he printed the sheet for it, I FOUND THAT THE ELECTRICAL DIAGNOSTIC PROCEDURE WAS IDENTICAL! This is the 89460-04010 sensor - it is current and can be purchased new for $245 (at least here at the local dealer).

After some additional searching on the web, I found a used 89460-04010 sensor ($75 + $5 shipping from http://www.tlspartsinc.com/). Once I received it, I tested it on my bench, verified that it worked per the Toyata diag specs, and put it in the truck. I had the shop reset the ECM (successfully). The replacement has been in place more than a week now without problem or additional engine check issues.

And, the really good news is that the 89460-04010 is also MECHANICALLY identical to the 89460-0W020!

I hope that this info helps others who found the original T100 PN nearly/actually impossible to find.

Toyota: why don't you publish that the Tacoma sensor is the same?!?! You could have saved a lot of your customers considerable grief! We like your vehicles, but this was a major pain to research and solve!

Thanks for posting this. I have the same issue on my new to me 97 in Texas!

 

Ditto

 

Toyota has basically thrown me under the bus with parts for my Echo. My first post here was about a manual rack bushing, right side, that they no longer offered as a replacement and for that matter any manual rack parts including the whole assembly. I found a replacement in the UAE and fixed my car, then found a parts car with a perfect manual rack that I now have in my inventory but have had trouble with the manual transmission 43,000 miles later after several years.

I guess the rationale is make it impossible to fix my car so I will buy something new, but I found a JDM manual transmission and it is being installed as I post this. About the only car available that can beat my mileage is a Prius C and $5900 with 170k miles is not quite my price range (Echo was $1600), so I will carry on with the Echo and my 98 Sienna. Why you can't get OEM parts for a 20 year old Toyota is beyond me, I guess they just made them TOO good back then and want the good old ones to go away. Funny thing is they still supply parts to other countries but not to the US. I think that may come back to bite them is the arse one day.

 

A lot of those discontinued parts from other countries are new old stock. They're not getting new stock from Toyota.

 

Git um while their hot boys bcoz I paid 22 bux fer mine b4 tax/shipping in early June '21 and it works great! It attaches a little different than OEM but still a fast install!

Pardon Our Interruption...

 

Well see if this takes away my CEL, ordered one

 

97Thunnid,
I cannot verify this for your vehicle but for myself and TXRailroads73 it does work great!

 

97Thunnid,
I cannot verify this for your vehicle but for myself and TXRailroads73 it does work great!

And it looks like you both have the 97 T100! I'm going to this a try. I have been going to junkyards and couldn't find the sensor so this will be a huge help. Thank you!

 

Another part number - I was getting 441 and 450 codes. Swapped out the pressure sensor and made things worse so removed it. I pulled the canister solenoid and no clicky clicky when using car battery - so started searching for solenoid.. Bottom line swapped both parts and no more codes...

amazon
Amrxuts 911-602 Vapor Canister Purge Valve Solenoid for Toyota Camry Solara T100 Lexus ES300 GS300 GS400 90910-12109 90910-12271 2502-310706* - $17

LSAILON Fuel Rail Injection Pressure Sensor Compatible for 1996-2000 for Toyota 4Runner 2.7L 89460-35030,89460-35030,89460-35030,89460-35030 Fuel Pressure Sensor

 

All:

This is my first post, and I want to use this opportunity to share how I finally solved the problem of the obsolete evaporative pressure sensor 89460-0W020.

I purchased a used '97 T100 in August 2013 with an inspection renewal a few months later (Dec 2013). Unknown to me, a previous owner had removed the engine check light from the dash. When I took the truck into the shop for inspection in mid-December, it failed because the engine check light did not come on briefly when the ignition was turned on. They looked further into the issue and found that the engine check light had been removed. They also found that the ECM reported a code of P0450 "Emission Control System Pressure Sensor Malfunction". Last of all, once they looked for a replacement for the sensor, they found that it was obsolete. (This, of course, is why a previous owner had removed the light.)

When the shop told me that the part was no longer available, I began a full-scale search for the part, pretty much coming up with dead-ends in the US. (I was entirely unwilling to spend $200+ to get a used part out of Japan or the UAE.)

I worked with the local DPS here in Texas, and they granted me a temporary waiver to give me time to find the part. Thank you Texas DPS!

Finally, after spending a lot of time at the parts counter at the local Toyota dealer, I found two really crucial pieces of information:

The first item was the actual diagnostic procedure to test the 89460-0W020 sensor: pull a vacuum of 8" water column (2.0 kPa), measure a voltage of 1.3V-2.1V; open the sensor to the ambient pressure, measure a voltage of 3.0V-3.6V; apply a pressure of 6" water column (1.5 kPa), measure a voltage of 4.2V-4.8V. I now had the information needed to validate a used part, if I could find one.

The second item - obtained only after pleading with the Toyota parts guy for more help - was to look up the same information on another model to determine whether a similar/identical part could be used. At first, he maintained that he had looked and found nothing. But, I wanted to see for myself and asked - specifically - to look at the equivalent sensor in a '97 Tacoma. Once he printed the sheet for it, I FOUND THAT THE ELECTRICAL DIAGNOSTIC PROCEDURE WAS IDENTICAL! This is the 89460-04010 sensor - it is current and can be purchased new for $245 (at least here at the local dealer).

After some additional searching on the web, I found a used 89460-04010 sensor ($75 + $5 shipping from http://www.tlspartsinc.com/). Once I received it, I tested it on my bench, verified that it worked per the Toyata diag specs, and put it in the truck. I had the shop reset the ECM (successfully). The replacement has been in place more than a week now without problem or additional engine check issues.

And, the really good news is that the 89460-04010 is also MECHANICALLY identical to the 89460-0W020!

I hope that this info helps others who found the original T100 PN nearly/actually impossible to find.

Toyota: why don't you publish that the Tacoma sensor is the same?!?! You could have saved a lot of your customers considerable grief! We like your vehicles, but this was a major pain to research and solve!

Super! Thanks for the very helpful history!

 

1995 and 1996 don't have these.

There are some instances like this where Toyota will not supersede the old part to a nearly identical one made for another vehicle, even though functionally they're the same. Often times with US produced parts, like the Tacoma one is.

Delco made these, hence why they fail regularly and not in production. GM is bad at producing parts for a long time.