Check Engine, Emission's failure and SEA FOAM

[mskhan18]

Hi all,

I have an '02 Camry LE, 119k on the clock. For over a year now, I was getting the CEL with trouble code P0442, code read by AutoZone. The thing is, the light would go off and come back on by itself so I just ran the car. I move in July to TX, and parked the car, with the CEL off. [I did not reset it, it went off by itself]. The car sat for about 3 months before I started driving it again about 6 weeks ago. The CEL came on again and I took the car to the dealer who gave me a whole list of trouble codes, P0442 etc with a repair estimate of 1900 greenbacks. I came back home, searched the forums and decided to sea foam the car. Its been about 3 weeks now. There is no CEL, no Codes, the car runs fine, as before, I get about 26 MPG in mix driving.

I want to figure out what happened here. The dealer wanted to replace the oxygen sensors, catalytic converter, a check valve located on top of the fuel tank, fuel cap, fuel filler pipe and 2 other parts which I forget. But now there is no light and the car runs fine. No hesitation, great mileage, great pick up etc. The car ran fine with the CEL on as well.

I am confused. Can someone tell me what's happening here

Thanks,
MSK

[CJCride]

I'll tell you what happened. You nearly got Reamed.
Plus the Seafoam seems to have worked.

[johnfrisco]

Originally Posted by mskhan18

Hi all,

I have an '02 Camry LE, 119k on the clock. For over a year now, I was getting the CEL with trouble code P0442, code read by AutoZone. The thing is, the light would go off and come back on by itself so I just ran the car. I move in July to TX, and parked the car, with the CEL off. [I did not reset it, it went off by itself]. The car sat for about 3 months before I started driving it again about 6 weeks ago. The CEL came on again and I took the car to the dealer who gave me a whole list of trouble codes, P0442 etc with a repair estimate of 1900 greenbacks. I came back home, searched the forums and decided to sea foam the car. Its been about 3 weeks now. There is no CEL, no Codes, the car runs fine, as before, I get about 26 MPG in mix driving.

I want to figure out what happened here. The dealer wanted to replace the oxygen sensors, catalytic converter, a check valve located on top of the fuel tank, fuel cap, fuel filler pipe and 2 other parts which I forget. But now there is no light and the car runs fine. No hesitation, great mileage, great pick up etc. The car ran fine with the CEL on as well.

I am confused. Can someone tell me what's happening here

Thanks,
MSK

Well it's hard to tell without knowing the original CEL code? Could have been as simple as your gas cap not being properly being tightened.

But yeah the dealer saw you as a wallboard and was getting ready to screw you.

[fenixus]

hahaha $1900 bucks, LOL I would start laughing at dealer guy...

you should go back to them and tell them how you fixed it... although i don't know what code P0442 stand for, here is a list of whole known P04xx code family on toyotas:

P0401 EGR Flow Insufficient.
P0402 EGR Flow Excessive.
P0420 Catalyst System Efficiency below Threshold.
P0430 Catalyst System Efficiency below Threshold Bank 2.
P0440 EVAP Control System.
P0441 EVAP Control System Improper Purge Flow.
P0446 EVAP Control System Vent Control.
P0450 EVAP Control System Pressure Sensor.
P0451 EVAP Control System Pressure Sensor Range/Performance.

seems, like dealer wanted to replace everything involved in this code family which doesn't even guarantee ultimate solution, since list is missing P0442...

[mskhan18]

Needless to say, the local dealer is on my NO GO list now

[toysarefun]

This might be that problem where overfilling the gas tank is the cause, how nice, topping the tank off for a long trip and you get a CEL. Happend to a friend of mine, she was pretty upset, it cost her about $300-400 to get rid of the CEL, forgot what it was exactly but I think this was it.

Check this other thread out. P0440 and P0442 codes and my concern...please help

[AlmightyCamry777]

That dealer's obviously some kinda crook is what happened.
I cleaned my throttly body once and decided to clean the MAF too and the engine didnt like that, and on went the CEL. I own a simple little code reader/resetter contraption i got from harbor freight and how it works is, you plug it in the OBD port, it flashes the code three times in sequences of 3 so you have time to read the code i guess, then automatically resets the CEL light. I cant remember the code because the problem and the light went away and never came on again. thus my little toy paid for itself ($30) the first time i used it.

The computers on modern cars are so sensitive there's plenty of times they'll turn on the light and throw a code for no reason at all (you can also reset the CEL for free by disconnecting the negative battery cable for several minutes then reconnecting). If the light comes on again, then you know you probably have a genuine problem somewhere and not the computer just crying "wolf". (And dont have to take some lying crook's word for it either).

[somick]

That could be a solution:

gas cap gasket

[fenixus]

true. this might be as simple as that. gas cap gasket is said to be replaced every 60k miles per my camry/avalon/solara Haynes. did it already and noticed better MPG.

[trooplewis]

Originally Posted by fenixus

true. this might be as simple as that. gas cap gasket is said to be replaced every 60k miles per my camry/avalon/solara Haynes. did it already and noticed better MPG.

Now that would be an interesting miracle. Care to explain how a better gas cap seal would give you noticeably better mpg???

[njerald]

It just keeps getting deeper.................

[fenixus]

Originally Posted by trooplewis

Now that would be an interesting miracle. Care to explain how a better gas cap seal would give you noticeably better mpg???

of course and no need to be sarcastic. i was observing worse and worse MPG over past few weeks, on 1 occasion i noticed (at gas station) no characteristic depressurizing sound, though it was there normally on most other occasions.

I did full tune up and MPG was still like crap (~20 MPG on avg, once it went down to 18) and getting worse even with better grade of fuel. finally i replaced that damn cap gasket and all is back to normal, MPG ~25 with mixed city/highway driving (around 27 with mostly highway driving).

[HotRod53]

I have the same code on my wife's Bonneville P0442, the scan guage shows "Evap System (slow leak)". I reset hers and it stays off for a little more than a week and comes back on.

I'm guessing that Seafoam will not help this, maybe you have a leak in one of your plastic hoses or rubber lines. I'm in the process of trying to figure it out on her car too.

[fenixus]

does it come back shortly after gas refill ? 1 week is the period ECM needs to confirm the pending code and throw it up.

[HotRod53]

Troubleshooting tip.... I spoke to my inspection guy today and he said that typically that is caused by a leaky purge valve. That code indicates a leak in the system that can be as small as a human hair. If the purge valve doesn't fix it you have to "smoke" the system. I believe that what he was describing was to generate smoke along the line to see where air may be blowing out. There are also some plastic lines involved.