Last post on Nov 09, 2013 at 5:09 AM
You are in the Toyota Camry
What is this discussion about?
Toyota Camry, Sedan
#5584 of 5646 Re: 2007 camry V-6 update [chuck28]
Mar 16, 2012 (2:25 pm)
The software version referred to in that TSB is for the operating system in the dealership scan tool which is used to check for codes. It is not a reflash of the computer.
Airtex/Wells is trying hard to create an image of producing superior parts. Some of their stuff is indeed better than the competition; while others are not. Their prices are more often set by marketing people than being a reflection of their manufacturing costs.
In the oxygen and AFR sensors listed for your car; Airtex comes in at the higher end of the price range; but NTK (part of the NGK spark plug company) is higher than they are on AFR (front) sensors. However; Airtex is the most expensive supplier of downstream sensors.
I really can't say whether their sensors are all that much better. I haven't had direct experience with that.
But I would like to further clarify the relevance of component quality (and sensors in general) with the problems you've been having. And the answer is ZILCH.
The codes you've experienced have NOTHING to do with the sensors on your car!!! Sure; the code definitions include the words "sensor is stuck in lean mode"; but this does not mean that a part or circuit in the sensor is physically stuck or malfunctioning. All it means is that the sensor is continually generating a signal that the mixture is too lean; when it usually would be varying from lean to rich. The word "stuck" is inappropriately chosen here (which is not uncommon for automotive publications that are written by semi literate people)
The sensor is basically a passive device, like a thermometer; which simply registers the percentage of oxygen in the exhaust gasses. If, for example, the fuel filter became plugged, and the engine became starved for fuel; the same class of code would be generated by the computer. But just because the sensor constantly reported that the mixture was lean would not, in that situation, mean that the sensor was defective. It simply means that the mixture is too lean and is not changing. It then is up to the diagnostician to determine why the mixture is lean and whether the cause has anything to do with the sensor's integrity or accuracy. If a vacuum hose or PCV hose broke or became disconnected; it would also lead to this same sort of code. So would an EGR valve that did become physically stuck open. And so would a cracked exhaust manifold, or loose exhaust manifold mounting bolts. And the oxygen or AFR sensor would be reporting the absolute truth in those instances.
Toyota has a 30 year history of building exhaust manifolds which crack or leak over time; and they still don't seem to have learned how to overcome this issue. The difference is that they didn't always redesign their mistakes in the 1970s; but now they are a lot more concerned about their public image.
Toyota's fix for this problem is to replace the cracked or leaking exhaust manifold with a part that has been redesigned to not crack or leak, and to install an AFR sensor which was made to work in the new manifold design. However; if an undamaged original design exhaust manifold was used to replace the cracked one, and your existing AFR sensor was transferred to the replacement manifold; the results would be identical to the official fix (until the manifold cracked or began leaking in a few years).
Many cars have misleading sounding trouble codes. My Geo Metro's computer will throw an "EGR system" code; if the ignition timing is incorrect; or if the fuel mixture is too lean. I used to beat my head against the wall trying to find the fault in the EGR system when I saw that code; until I eventually learned that codes are crude approximations of the possible reasons why sensors report what they do. This is why computer codes cannot be taken literally; and why a broad perspective of how an engine functions and how the various systems interact is indispensable for troubleshooting computer codes.
#5585 of 5646 Re: 2007 camry V-6 update [zaken1]
Mar 17, 2012 (12:01 pm)
"...learned that codes are crude approximations..."
Factory engineers put a lot of effort in creating a diagnostic flow chart for each "foreseeable" code condition that might arise. If you follow that chart upon having the system generate a fault code, or codes, my educated guess would be that more than 70% of the time the chart will take you directly to the cause of the fault.
Are there exceptions, certainly.
For over 10 years my '01 RX300 has had a "habit" of generating a "bank 1, sensor 1, fault code". Back many years ago, ~10, probably when it first happened, I went to Lexus and purchased a new oxygen sensor.
Before I found time to install the sensor the fault cleared of itself and I put the new sensor away in the spare tire well. It has remained there until just last week.
Over the interim years the RX has "thrown" that very same code at least 3-4 times. Each time, due to the first experience, I would wait for a period of time to see if the fault would clear, which it did.
About a year ago I purchased a "generic" oxygen sensor to replace one of the downstream sensors in our '95 LS400. To assure myself that I would be connecting the 4 wires of the generic sensor correctly I heated the sensor on an electric range in order to find the proper connection polarity. The 2 wires for the sensor resistance heater was very easy to isolate.
So having assured myself that the connection directions that came with the sensor were correct I installed the new sensor.....Oh PISS, I had the same fault code......
Within a few days I took the sensor I removed, heated it the same way to assure myself of the proper installation polarity of the new sensor. Strange....the "failed" sensor, except for having a higher heater resistance, 16 ohms vs 12 for the generic, seemed to produce an output voltage that equaled the new one when/while HOT and exposed to atmospheric oxygen.
In the meantime the '95 LS400 sensor fault cleared of itself....
Had I somehow compromised the sensor element by exposing it to atmospheric oxygen while heating it...??
It was about this same time that I ran across a post, LS400 oxygen sensor code, wherein a cracked exhaust pipe nearby the sensor had resulted in a sensor fault, seemingly.
Apparently the crack was allowing atmospheric oxygen to reach the sensor element while it remained HOT even after the engine was switched off. Fix the crack, the sensor stopped "throwing" codes...
Does this begin to sound altogether too familier...?
But how could this be happening in my RX without a crack in the pipe, etc.
Oh....In my '01 RX300 when VSC/Trac activates the engine MUST be dethrottled. Since the throttle plate is HARD attached to the gas pedal the only way the dethrottling can be accomplished is via EFI engine fuel starvation.
TC activates, throttle OPEN, NO FUEL, HOT sensor, sensor exposed to atmospheric oxygen....
Do my RX300 oxygen sensor failure code events correlate to VSC/TC activation..?
Conclusion: Exposing the oxygen sensor element to a high oxygen atmospheric content while it remains heated, HOT, seems, appears, to modify the sensor characteristics for some extended period of time.
Last week I heated, on the electric range, the NEW oxygen sensor that had remained in my RX300 trunk for the past 10 years and installed it. It took 3 days (daily driver) to clear the resulting oxygen sensor FAULT.
#5586 of 5646 Re: 2007 camry V-6 update [wwest]
Mar 17, 2012 (2:22 pm)
Just wondering, could the RX3OO have had a cracked pipe or manifold gasket leak that was not detected during this period?
#5587 of 5646 Re: 2007 camry V-6 update [chuck28]
Mar 18, 2012 (1:36 pm)
Might have been but since the new sensor seems to have fixed it for the moment..only time will tell.
Plus which my memory seems to be that each past failure was the result of an extended VSC/TC activation.
Additionally the periods between those failures have been measured in years. So it seems to me that a cracked or leaking exhaust manifold/pipe would have resulted in failures a lot more often.
#5588 of 5646 Re: 2007 camry V-6 update [zaken1]
Mar 18, 2012 (7:16 pm)
Hi Zaken, I was wondering from the time I had code P2195 Fuel-air ratio code and changed that sensor it was 3 months until the P0138 oxygen sensor code kicked in. I was wondering when I replaced the first fuel -air sensor (2195) why did I not get a check engine light if the initial code was triggered by the defected exhaust manifold?
I haven't got a chance yet to have ht manifold looked at.
I appreciate all your help and wisdom.
Thanks greatly, chuck
#5589 of 5646 check engine light update code 2195 & 138
Mar 22, 2012 (7:40 pm)
Still waiting to have manifold looked at. This morning filled up tank with Premium and after pulling out of gas station Check engine light was gone. This is a first since the light has come on. It's never gone off by itself only when code was rest by disconnecting battery. Tonight as I hit the highway for a short trip lights came back on.
Still thinking Zanken explanation about the manifold makes sense but wondering why light when off. Was it the fuel give a new reading to the computer?
Looking for insight, thanks, chuck
#5590 of 5646 Re: check engine light update code 2195 & 138 [chuck28]
Mar 22, 2012 (9:14 pm)
This sounds to me like the manifold may have either been jarred or twisted slightly when the sensor was replaced; and that amount of movement temporarily sealed the leak. Then, three months later, the manifold moved enough from vibration for the leak to open up again. The likely cause of the light temporarily resetting just now was a combination of expansion and temperature changes during what I assume was the short drive from your home to the gas station.
This all sounds to me more like loose manifold bolts than either a cracked manifold or a damaged gasket.
#5591 of 5646 Re: check engine light update code 2195 & 138 [zaken1]
Mar 23, 2012 (3:20 am)
Thanks Zaken, I appreciate your wisdom this makes sense. I will have the botls checked out. Will keep you updated. Might not get to it till next week.
Thanks again, chcuk
#5592 of 5646 2007 Camry LE V4 - Replace Water Pump - Engine Coolant Seep
Mar 23, 2012 (8:47 pm)
Need help from the experts on my 2007 Camry LE V4 - 64K miles
Went in for oil change to the Toyota dealer today and the service guy said that the water pump needs replaced. Per the service notes "Engine coolant seep" failed pressure test. The dealer quoted $560 for parts and labor (Southern California, Orange County).
There is no leak on my garage floor and I could not find any leak around the engine. A lot of folks mentioned that they notice pink stuff when the water pump leaks.
The car runs very smooth and I never had any issues with overheating and never noticed any leaks.
How would I make sure that the dealer is really honest and in fact there is a real issue with the water pump ? (Dealer wanted $290 to change the indicator bulb, last month. Took it to a local mechanic and he replaced the indicator bulb for free, just paid $8 for the bulb.)
Can the water pump be replaced by an outside mechanic, and how much would it cost if it's done by a local mechanic - can they test and confirm if there is indeed an issue with the water pump?
Thanks a lot in advance for your help.
#5593 of 5646 Re: 2007 Camry LE V4 - Replace Water Pump - Engine Coolant Seep [sdizdabest]
Mar 25, 2012 (11:29 am)
It could be possible that there is a cooling system issue with your 2007 Camry because my family owns a 2007 Camry and we are a Consumer Reports subscriber--back in 2006 we were reluctant to buy the first year of a new model redesign but we had no choice because our Chevy was basically dying (at less than 100k miles!) and we already had a Honda Accord so we decided to "gamble" and go with the '07 Camry. Anyways, we noticed recently that Consumer Reports shows that the 07 Camry overall is reliable (full red and half red marks for reliability--except for "Engine Cooling"--where it shows "half black"), so it got me worried--fortunately, if what you described is the extent of the "Engine Cooling" problem, then we can handle that (~$560). However, it wouldn't hurt to get a second opinion, I've been burned three times by my local very well known Honda dealership, see this post here: http://townhall-talk.edmunds.com/direct/view/.efdf924/5611#MSG5611