Check engine light - three more questions

Hello and thank you for the welcome to Tacoma World. Last November I bought my 2nd Tacoma (bought a 2002 new and should have kept it) in Arizona before shipping it to our new place of residence on the Big Island of Hawaii. About a month ago the notorious "check engine light" came on, and that was when I found this terrific web site. I did learn valuable information right away - like what to do if you're a dumb ass and disconnect the positive battery cable before the negative one. Thank you.

My 2003 Pre-Runner has 112,000 miles on it, and only had one owner before me. Last month the light came on, and I made an appointment with the local (only 1 of 2 on the island) Toyota dealer. The soonest appointment was 2 weeks out, so I tried to figure it out myself, which led to the experience I just described.

Appointment day came and it was discovered that I had a cracked gas cap. (I always make it a point to tighten the gas cap, but did not know it was cracked). Then another code - this time for upstream O2 sensor, S1B1. I had them replace it, paid $120 for reading the code and $400 for sensor. (It hurts just to admit that)

I came home and looked for the online price of such a sensor - anywhere between $70 and $150.

The next time I drove the truck the light came on again. I called the dealership, made sure they would not charge me again to read the code, and made an appointment. That was a over a week ago, and finally, my appointment is this Friday.

Here is the 1st question - what are the odds that the code will turn out to be the downstream O2 sensor?

Second question - if not the downstream sensor, what are the odds it is a catalytic converter sensor, or something else?

Third question - shouldn't I just replace all the sensors that seem to fail anyway at some point? Which ones?

My plan is to consider your advice, go down to Car Quest or NAPA, and buy those sensors, and take them with me to the dealership. If they won't put them on, I need to find a reputable mechanic anyway.

Thank you (Mahalo), Footy

 

I would take the truck somewhere where i you can get the code read for free. O'Reilys read the code on my tacoma for free, and the check engine light was for a MAF sensor. I did buy a new sensor from the dealer but didn't pay for the scan. That way you won't be paying Toyota out of the a$$ for a simple scan to see what is wrong. As far as whether or not you downstream O2's are bad, I am not sure. I have nearly 180,000 miles on my tacoma and the MAF was the only sensor that has ever gone bad. And if O2 sensors are costing $400 a pop, I wouldn't replace one unless it was necessary.

 

Hey Footy,

i wouldn't hold out hope that the dealership will put in your aftermarket part. (you can see how much they're making on markup) find a good mechanic in your area and the relationship will pay off in the long run. If you've ever thought about trying your own car repair, this is a great vehicle to start with. Most things on it are fairly easy to do with a small set of tools, and there's a wealth of knowledge on this site.

 

Wow, that was a fast reply! Yes, the next scan at the dealer is at no cost, so I'll let them do that. I believe there is an O'Reillys in Hilo, so I will try that for sure next time.

Thank you.

 

Thank you also TooMuchToDo, that looks like my truck. My wife said the same thing - no way they will put on a part that I didn't buy from them. I'll let them read the code though..

 

Yes, most autoparts (advance, Autozoone, etc) will check it for free on the spot, no appointments. I'd also check your fuel pressure before you go throwing parts at a pretty broad problem.

 

98tacoma27 thank you too.

 

Hadn't thought of that Sandman, thanks.