Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: KD on November 03, 2009, 07:34:50 PM

Title: shop replaced O2 sensor, but check engine light is still on
Post by: KD on November 03, 2009, 07:34:50 PM
Hi there,

I've got a problem with our Jeep again and hope that somebody here might have some expert advice for me.

About 2 months ago my check engine light went on every now and then. I had a diagnosis from one dealer saying that the downstream O2 sensor needs to be replaced. Not knowing much about Jeeps at all this just made sense to me as the Jeep seemed to be really slow uphill and with strong winds coming from the front it doesn't drive any faster than 120 kmh.

However, after having had issues with that dealer I decided to go to another repair shop and they replaced the sensor. Unfortunately the check engine light didn't disappear and they said they need to take a look at the wires as it might be an issue with the electric. They ran another diagnosis and showed me some wires next to the battery which were covered by battery acid and they said they´re going to replace the affected wire and everything will be fine then. I picked up the car again and after an hour the engine light went on. So I brought the car back to the repair shop. They ran another diagnosis and said it has to be a problem with other wires or most likely, the computer.

When they mentioned that they need to check the computer and any related wires, circuits etc. and that nobody could say how long this might take (but definitely really long), I took the car home with me as letting people work on the car for an unlimited amount of time for a very high hourly rate didn't sound good to me.

Is there any way I could find out myself what the problem is or at least learn more about the amount of time that is really needed for such an issue and where the problem could lie?

Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: FiEND on November 03, 2009, 07:37:11 PM
keep driving it and try a different gas station.  esso is usually good, try a couple tanks of that and see if the light goes out.
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: KD on November 03, 2009, 07:46:40 PM
Hi! Thanks for the quick reply! Why do you think the gas has something to do with it?
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: TJ54 on November 03, 2009, 08:19:52 PM
i don't know what kind of jeep you have, but if is newer than 97, go to can tire or napa etc. buy a obd 2 code reader and start diag yourself and Just keep throwing parts at it untill you find the issue.
Send me a pm about what codes you find and I'll give a reasonable time of what a shop should charge for the job.

with alot of jeeps you can read the codes from the odometer,
not as accurate as a code reader, but a good staring point.
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: hps4evr on November 03, 2009, 08:35:41 PM
from my own experience. there are a lot of crappy aftmarket O2 sensors out there. the only ones ive seen work perfectly are the oem sensors. the dealer may be right, just the corner shop put in shitty parts.
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: TJ54 on November 03, 2009, 08:47:54 PM
from my own experience. there are a lot of crappy aftmarket O2 sensors out there. the only ones ive seen work perfectly are the oem sensors. the dealer may be right, just the corner shop put in shitty parts.

agreed,  

although the bosch ones are pretty good
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: hps4evr on November 03, 2009, 08:51:21 PM
oops, its true, the bosch ones are the one good aftermarket sensor. if it plugs right in its a good one. if you have to splice the wires in, its poop.
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: Axemanjay on November 03, 2009, 10:05:29 PM
Alot of places will do the code read for free... Autovalue for one.
Title: Re: shop replaced O2 sensor, but check engine light is still on
Post by: jkrubi on November 04, 2009, 12:56:07 AM
obd 2 readers go on sale at princess auto every couple of months for under a 100 buxs.  I got mine from there works good for me will turn out the light, and tell you what code is throne or as stated you can go to some parts place and they will read it for you for free or a couple of dollars.