Engine check light comes on intermittenly.

Hello there,

I have a 2002 Tacoma, basic model with the 2.4 engine, Calif model, 245,000 miles.

The engine check light comes on for a few weeks and then it goes off for a few weeks, it has been doing this for about five years.

The light is off when i get it smogged every two years and it passes smog.

My brother who is a german car mechanic has scaned it and is not sure what it is. He suspects the catalitic converter.

Very curious as to what you all think here, This forum is a wonderful resource.

Thanks,
Peter

 

Interesting.
You'll have to scan it while the CEL is on to know for sure.
You can pick up a bluetooth OBD2 scanner for your phone and use it with an app or you can stop by most autoparts stores and they will scan it for you.

 

Need a code to even begin to keyboard quarterback...

 

Guessing P0420

let everyone know

 

Ok, I will wait till the light comes on and get it scaned, I will report back here, much thanks.....peter

 

Evap codes will do this. Next time you put fuel in it notice if there is a pressure sound as you take the fuel cap off. If you do this a couple of times and dont here the sound ill bet that the cap is intermittantly not sealing.

 

The check engine light has come off and on a few times on my Tacoma
and i went a auto parts store. The salesman scanned it and it had the following codes:

P04020 current cat efficiency. P1135 toyota current air fuel sensor bank one. (not sure if I wrote the second one down exactly as he told me)

The guy told me about a product called Cataclean which he said was very good and i bought a bottle and put it in the truck.
The check engine light stays on all the time now. Very interested in what you all think of this. Much thanks, Peter

 

The P1135 for the AF sensor could very well be causing the P0420 code as well. I would start by replacing that sensor.

But if the air/fuel ratio has been too rich for too long that will easily damage the catalytic converter(s) and also result in the P0420 so it may be that you need new cats at this point. I would start with the AF sensor though since you're getting that code as well.

 

The engine control computer uses the signal from the air/fuel sensor to help calculate if the catlytic convertor is working as designed or not. I do not advocate putting in a part just because the scan tool says so. The problem is is that by the time you have a tech look at the truck and pay for his diagnostics you could have probably put the air/fuel sensor in yourself. If you choose this route, you will have to have the auto parts store clear the codes for you so that the self tests can run. Toyotas are VERY sensative to aftermarket emmission control parts and saving dollars directly on a part could just cause diagnostic issues later, I mean, its a brand new part, how can it be "bad"?, happens ALL the time.

 

Screw tht $30 catclean

few options here

https://youtu.be/5icTmYItwiE?si=fbb-eWxwwhhycvdw