Check engine light at 70,500 miles, darnit

[Jake's Dad]

..I just got this truck used, drove it for about 400 miles and the check engine light turned on. I owned a '96 Explorer once and the light came on due to a sensor but had no real significance. Anybody know what to look for trouble wise?? Darnit - right before a trip with the family.

JD

 

[Alec]

Often the CEL isn't that much to worry about if the truck still runs well. I'd get the codes scanned, let us know what codes you pull.

A good investment might be your own code reader. A cheap one (like mine) is about $150 and just pulls the code numbers, which you then look up in the book. Some are around $300 that give you real-time info and other cool stuff. Then there are the pricey ones, but you don't want one of those.

But most places usually charge about $60 to pull a code for you. Autozone does it for free sometimes, or if you pester them Good luck!!

 

[Jake's Dad]

Well Im at work now and have to drive it home - we'll see what happens. Thanks for the help -

JD

 

[aldive]

If you are looking for a good scanner, take a good look at the Auto X Ray scanner.... http://www.autocheckup.com/default2.htm

Be sure to post your codes once scanned.

 

[Jake's Dad]

Ill post ASAP. I can't afford the reader yet, I just bought new rims, shocks, plugs, wires, and flushed all fluids. WHEW! Then this....uhg.

JD

 

[Jake's Dad]

This truck also failed an Ohio emissions test a year before I bought and drove it back to Michigan. I found this out on carfax. It also showed it passed the next day.

 

[Robert]

It could have failed the emissions test for any number of reasons, including a leaking gas cap which will also set off your CEL. Go to Autozone and have them read the codes for free. Don't let them talk you in to buying anything though until you post your codes here first. The local radio stations around here have been playing the Autozone comercial a lot for the last couple of weeks advertising their free engine scan.

 

[Jake's Dad]

Before I drove the vehicle to auto zone, I checked all fluid levels and they were normal. I drove 32 miles and all the gauges were reading in their "normal" range.

Scanner read:

P153
02 Sensor
Bank 2 sensor

I remembered this with another X I owned. No big deal. I'll be back after a 600 mile trip to report.

Thanks gang-->> <<--


Jake's Dad

 

[Alec]

cool. you should probably go ahead and change your O2's before the trip as they might cause you to start running rich if they're going bad. But I tend to fix things too hastily sometimes.

 

[Robert]

I agree with Alec. Since the O2 sensor is your upstream sensor " P0153 Oxygen Sensor Circuit Slow Response (bank 2, sensor 1) ", if you are running rich it could take out your catalytic converter. A new catalytic converter is $800. A new O2 sensor is $50.

 

[Jake's Dad]

Well I didnt have time to take it in before the trip. I went 600 some miles and the light never turned back on after the guy at Auto Zone reset the memory (or whatever you call it). I'll take it in. I have zero experience with sensors.

JD

 

[Jake's Dad]

I have an IAC on order - Ill let everyone know if that helps fix my idle problem in case it does. Anybody know how hard it is to replace an 02 sensor??

JD

 

[jasonb]

are all the reasons the "check engine" light comes on emissions related? that is the what the manual makes it sound like. mines been on twice for the fuel cap. its on now too.. off to autozone at lunch.

 

[Jake's Dad]

Well, I don't know the answer to that. Anyone that has the a reader with the book can tell you that. I'm sure that if your engine had any problems that the CEL would come on. I do remember when I owned a '96 that the CEL came on when my alternator was failing. Chances are that it's a sensor if all of your gauges read normally. Check to see if any fluids are leaking, then just drive it easy and keep an eye on the gauges on your way to auto zone. If the CEL starts blinking - pull it over immediately.

Good luck!

JD

 

[tlc_sport]

Same problem

My CEL is on as well and I have the same code (P0153). I bought the O2 sensor at Autozone and my stepdad and I are putting it on this weekend. He says it's not that hard to do, but I don't have any experience with sensors, so I wouldn't know.

I was told that, if your O2 sensor is bad, you would not pass emissions. Well, I passed my emissions test and my CEL was on at the time with the P0153 code. Is this possible or could I be getting a bad code? It has been cleared out of memory twice and came back both times.

-TLC

 

[Jake's Dad]

Hmmmm. I doubt seriously that you are getting an improper reading. Sometimes you can pass an emissions test if they stick the thingy too far in the tailpipe or whatever. All I know is that you and I both should change that sensor before the cat goes and that is expensive!!!!!!!!


-JD

 

[tlc_sport]

Is the bank 2 sensor 1 O2 sensor before or after the catalytic converter?!? I believe there are two O2 sensors, is that correct and, if so, should I replace both or just the one that is getting the code?

 

[Robert]

jasonb - Officially, yes anytime the CEL is on it has to do with something that can cause a problem with emissions. For instance when your CEL came on because of a bad/loose gas cap, it failed the fuel system pressure test. If you cap leaks, it could allow fuel vapors into the atmosphere. Unofficially though, I have seen the CEL come on for reasons that as far as I'm concerned won't really affect the emissions. One thing that comes to mind is a failing IAC valve. The only thing that would cause is that your engine won't idle on its own. Your emissions wouldn't be changed any unless they consider the extra emissions that would be put out from restarting your Explorer every time it died.

tlc_sport - Bank 2, sensor 1 is the sensor before the catalytic converter on the side that doesn't include cylinder # 1 (the side with cylinder # 1 is bank 1). From memory, I think bank 2 is the driver's side. As to whether or not you should replace both on that side or not depends on how quickly they are switching from low to high voltage. Per the Ford test procedure they should switch at least every 3 seconds. You will need a scanner to watch them. If they are both very slow to react then replace both. If only one is acting up then replace it first and then monitor your other one. At $50 apiece it would be a waste to replace an O2 sensor that is working properly.

 

[jasonb]

yeah i put a new iac on pretty early on in the life of the x. fun to drive with the 2 foot shuffle.
i'll take her to autozone and get the free reading.

 

[tlc_sport]

Thanks for the info!

I'll see about getting my hands on a scanner to test. The O2S will be replaced this weekend, so I will let you guys know how it goes.