Northstar Engines and System Technical Discussion Discussion, Oxygen Sensors......Need help soon!!! in Cadillac Engine Technical Discussion; Oxygen Sensors............Need help soon!!!!!!!!!!!! I have a 1997 Eldorado (ETC) which I recently had a blown head gasket fixed.
Oxygen Sensors............Need help soon!!!!!!!!!!!! I have a 1997 Eldorado (ETC) which I recently had a blown head gasket fixed.
Time Certs and the works done.
I just had four oxygen sensors replaced yesterday, today the Service
Engine Soon light came on. I ran the dianostic and it gave me the same
four oxyen sensors I just replace a day ago.+ a MMM-B2150 CODE.
I called the machanic that installed the sensors and told him what happened and he seems to think that it is my Catalytic Convertor causing the
Any help will be appreciated!!!!!THANKS IN ADVANCE
P.S. Just want to say what a Great forum this is!!!!!!!!!!!!!!!!!
Had something similar happen to me with a past GM vehicle where a clogged fuel filter caused the O2 sensors to go bad along with the catalytic converter. The good new for me was the catalytic converter was covered under the factory warranty up to 80,000 miles instead of the standard.
Can you please post the out come of your problem.......I just replaced all four of the O2 sensors in my 96 STS and so far the light hasn't been back on but who knows it might come back on next week so I would really like to know the out come. You know three of the O2 sensors are very easy to change but the fourth one that's by the fire wall behind the coil was hell to change....I had to removed the coil and the blower motor just to have room to get to it (are you sure your mechanic changed that one?) did you see all four of the old ones? Keep me posted my friend and I hope everything works out for you as well.
It could have been coincedence or somethign... WHat I owuld do is take it out for a few good WOT blasts and see if that doesnt help..... Things need cleaning and thats the easiest and most fun way to do it!
Yes, they are all GM Cadillac parts,, or that's what the mechanic told me.
The one's from the dianostic were "P0135, P0141, P0147 and P0155. Also
I got a MMM-B2150.
WOULD LIKE TO THANK YOU ALL FOR YOUR HELP AND SUGGESTIONS;
I WILL LET YOU KNOW THE RESULTS!!
THANKS AGAIN GUYS!!!!!!!!!!!!!!!!
Check your fuses; all your "P" codes relate to "O2 sensor heater performance" problems. I have no idea where 'your' fuses might be located because my Service Manual is for a Seville. Under the hood is a good place to start. Look for a fuse that is labled something like "OXY SEN xx".
DO NOT replace your catalytic converter. If the converter was degraded you would have retrived DTCs P0420 / P0430. If your ho2s fuse is good like you say I would check your ho2s G-250 ground circuit, this ground circuit is related to all 4 sensors, I will be willing to bet it was left loose when the tech replaced your headgaskets. Lets us know what you find.
I think FrankT might be right. Looking at the codes/diagrams....all use ground circuit 250. The actual ground is G109. G109 is located 'left hand rear corner of the engine, near the park/netural switch.'
I dont think the cat is bad.
Also, it would be very easy to put aftermarket O2 sensors in and call them GM ones...
I took the Cad to Midas Muffler this morning and they said that the Catalytic
Converter had no cracks and was good. (This was before I read the recent
post on the forum). Anyhow, he asked if the machanic that put in the oxygen
sensors clear the codes with a scanner after he finished. I told him I thought
that he did, but wasn't sure. So cleared them (P0,,codes) with his scanner.
So for the "Service Engine Soon" light is out. I sure hope that it stay that
I sincerely thank all of you for the very helpful support that was given on
this forum and God Bless everyone of you!!
Today I drove the Cad about 26 miles and the "Service Engine Soon" light
has not come back on since the guy at Midas cleared all of the old codes
from the oxygen sensors. I hope that this is all that was wrong!!!!
Thanks again for all of your help, much appreciated!