DIY - Check/Replace your CPS Sensor

Are you tracking for misfires as well? While my truck's mileage has improved and overall drivability have improved, I continue to be puzzled by why it records the occasional misfire or two. I was always raised that misfire = bad = something wrong but am I just being paranoid and since it's only one random cylinder at a time and generally only happens 1-3 times per trip this is indeed "normal" and I should stop being OCD about it... ?

 

When you replace a part, such as the CPS, on your own, does that void your bumper to bumper warranty if the truck is still under it?

 

No

 

I'm thinking that if my truck makes it to the recall list then right before I go in for servicing I'll put the stock CPS back in (since it didn't quit working yet) and have it replaced with a new one then go back home and put my "old" new one back in and sell the "new" new one rather than deal with trying to get the money back from Toyota.

 

In this case, I believe the letter serves to notify you that the recall is active, since it is still an interim recall at the moment. Meaning if you bring it in to the dealer, which I did for this recall, they will not do anything since Toyota has not officially released a remedy or a redesigned CPS. So I'm also waiting for the letter/checking the toyota recall website to see if the recall is active (which it isn't as of today).

According to shakerhood, my warranty shouldn't be voided if I do it myself, so I might order the part and do it. HOWEVER, when I called the dealer today to see if they would be willing to change the CPS with the old design, they said the old design doesn't exist anywhere in North America, and so they can't do it. I think that's bullcrap since I went to parts.toyota.com and they're allowing me to order the crank position sensor

 

Is there a reason you would want the old design, that is the one that is subject to failure? If I were ordering one to swap out I would be making sure it is the new design and you will have no issues with your warranty by simply replacing a sensor with another Toyota sensor.

 

I confronted my dealership SA 2 days ago on this CPS recall and asked him a simple question " if the CPS recall is only for those that fall under the guidelines of this:

Then why can't you just install a new CPS sensor that was made post October 2016 that's not on the recall list while we're waiting for the official fix?

He says " because Toyota doesn't have a remedy yet"



But FYI if you do replace the sensor yourself pre-recall "Fix" by law they will have to reimburse your expenses.

 

So this tells me two things. Those of us NOT on the recall either 1) Dont have the excessive coating on the crankshaft rotor itself or 2) We may, but have the sensor that contains "anti-electrification" whatever the heck that is. Looking forward to learning more. Either way, I'm glad I did mine and have a spare.

 

So CPS replaced and within two days, check engine light came on. No drive issues this time. Took back to dealership and they checked it out. Said they had to Send data to Toyota to review and it was a Saturday.

Truck driving fine and they reset everything so no CEL. Called me Friday and told me catalytic converter was bad. 24K miles. Hard to believe.

Also read something on TW that you could get a catalytic code some after CPS replaced.

Any one else run into this.

 

From the service manual:

When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high
hydrocarbon concentration levels can cause an increase in exhaust emission levels. Extremely high concentrations
of hydrocarbons can also cause increases in the three-way catalytic converter temperature, which may cause
damage to the three-way catalytic converter. To prevent this increase in emissions and to limit the possibility of
thermal damage, the ECM monitors the misfire count. When the temperature of the three-way catalytic converter
reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the
VVT sensor and the crankshaft position sensor. The VVT sensor is used to identify any misfiring cylinders and the
crankshaft position sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted
when the crankshaft rotation speed variations exceed predetermined thresholds. If the misfire count exceeds the
threshold levels, and could cause emission control system performance deterioration, the ECM illuminates the MIL
and stores a DTC.

@bshammer0

 

It's definitely possible your cps was causing your truck to run rich, and caused your cat to fail from running too hot. Should be covered under warranty and not the recall.

 

Definitely is possible your cat was destroyed by running too rich. I'm sure the life of mine has been reduced, but mine hasn't failed on me - it would have. There were times I was smelling sulphur from the exhaust pre-CPS, and hell - one time I pulled into camp after driving 200miles to a river and the first thing the guys I met up with said was "do you guys smell gas?"

In any case, I actually never threw a code. According to TechStream I was driving a perfectly running truck and complaining about nonsense No doubt my cat would have started to fail on me if I'd driven it like that for much longer.

For me this CPS has been a life saver. My wife even asked me yesterday why I don't drive it like a race car anymore. Because I don't HAVE to. D actually is useful and will hold 75mph even with grades @1,800 RPMs (just below that 2k harmonic range). My throttle response is actually pretty good right now, steady acceleration without slamming on the throttle AND I made a 120mi round trip yesterday. The exact same trip UNLOADED for me 16mpgs a few weeks ago. Yesterday I was loaded down with a few hundred pounds of gear, curvy, hilly roads driving 55-75 the entire time.

MPGs = 21. And my vibes are slowly dissipating more and more as well. People are driving these trucks around living with "normal" characteristics they shouldn't have to....

 

All of this was very helpful. Sounds like I might get some performance and MPG improvement as well.

 

I'm getting in the upper 14s low 15s in town....my truck only has 500 miles on it, but still, I'm thinking I should not wait for a possible recall and should switch mine out now just to save any premature CC wear....hmmm

 

What was the build date of your truck? if the only issues you are experiencing are MPGs and all else is good I would probably at least get to over 1,000 miles. Most times when you do a reset (such as unplugging the battery to clear learning), MPGs start out on the low side then slowly increase. In my case, I saw the real improvements after 1,000 miles post CPS from an MPG standpoint.

But, MPGs were the least of my concern at the time... silver lining was the increase in MPGs

 

It's March or April '17.....so I figured I was safe...but now I'm thinking not...but you are right. I don't think I'll do anything till post 1k miles and give it some time to see if the recall is expanded...I'm thinking it will be. I like the Tacoma...but after coming from a 2005 Tundra with a seamless power delivery and 13 MPG city the Tacoma with it's "twitchy" drivability and 15 mpg city is a disappointment...I was expecting a minimum of 18 combined, which is simply the city rating.

 

Give it a bit of time, also takes a bit for the twitch to calm down as it learns. The "new" CPS many of us have installed showed a build date of April '17 so if your's was built around that time I'd have to think you have the newer CPS but who knows. I wouldn't be surprised if the design itself is simply flawed and they will all degrade under heat soak over time. But I have to say, driving in stop-go traffic this AM for 15 miles in D (which was useless to me the first 13,000 miles I owned the truck) with buttery smooth shifting (and often holding 6th when it used to HAVE to be in 4th to maintain speed) with a trip average of 21 mpgs is a welcome change.

Keep us updated on here as you clock more miles though. Will be interested to see some additional data points from trucks built recently...

 

Mine was built in March 2017 in Texas and my MPGs have been pretty consistent at around 20 since day 1 but the past 2 tanks have been 22 and 21.

 

I'm curious with MPGs affected by the CPS if Toyota will step up with a gas remedy. I've know manufactures to offer gas credits as settlements.

 

Ha - Nice thought for sure... but they'd first need to acknowledge that more than 30,000 trucks are affected. Right now Toyota hasn't even acknowledged this as big of an issue as it really is imho... Once they start having to replace catalytic converters and more stalling occurs maybe they'll take it seriously. Whole lot easier to replace a damn $100 part than what is about to happen the more of these that keep rolling down with bad CPS.