Check Engine Light is on all the time. O2 Sensors?

SteveW · 09-18-2002

My son has two Mustangs (he got addicted somehow)
His main driver is a 96 with a V6 and 5 speed. Drives and runs great. Problem is the check engine light is on all the time. Ford garage says it is either the O2 sensors or the Catalytic Convertors. All are very expensive for someone trying to put back together a 68 mustang also.
Questions....
How can I be sure which it is...sensors or cat convertors.
Which is the cheapest/best way to get it fixed....
It appears to me that the car has 4 cat convertors....two on each exaust line. Is that possible?
Any help would be greatly greatly appreciated!!

Ron · 09-18-2002

I had the same light come on mine, and it turned out to be the O2 sensors. I went with the sensors first as they were the cheaper and easier fix. I would start there, or maybe a good exhaust shop could check the cats to make sure they were ok. Yes the new cars all have 4 cats....

SteveW · 09-18-2002

Quote:

Originally posted by Ron
I had the same light come on mine, and it turned out to be the O2 sensors. I went with the sensors first as they were the cheaper and easier fix. I would start there, or maybe a good exhaust shop could check the cats to make sure they were ok. Yes the new cars all have 4 cats....

thanks for the reply.... I am not very mechanical.. (my son is, obvioulsy) I checked prices on the sensors, and they said there was an upstream and downstream sensor. I have seen (and taken out and cleaned) the downstream ones...behind the cats, but cannot see the upstream ones. Any thought as to where they are located.
Our ford dealer priced these to me at about $102 each. (ouch)

Ron · 09-19-2002

Sorry, not much help on the exact location.... I had a shop do the work for me. I don't remeber spending that much on them though. The upstream ones would need to be in front of the cats and after the headers. That is going to be a real tight fit to get to.

milw96cobra · 09-19-2002

Well, the easiest cheapest way to 'fix' it, Get some MIL Eliminators... Unplug the wiring into the O2 sensors and plug them into the MIL's they basically trick the computer into thinking that the O2's are working properly....

www.partshopper.com sells them.

milw96cobra · 09-19-2002

http://www.partshopper.com/catalog/itemdisplay/464.html

There's the direct link... they sell them in pairs.

Oh and I guess you splice them inbetween the wiring....

SteveW · 09-26-2002

I had our local Ford Garage run the tests on his Stang....
they came up with one bad 02 sensor, and a FTP sensor. The also said the Cats ar going out so fixing the O2 sensor will only be very temporary....
their total estimate was 1600 for parts plus the labor to install them,

I am going with the MIL eliminators. Hope they do the trick...
thanks for all the help.

CobraClone98 · 09-26-2002

Get the cats removed, completely and install two hi-flow cats. any muffler shop can do it. Replace the o2 sensors. all of them if you can afford them at that time. if not just get the o2 sensors that are on the headers. and get the MIL eliminators. for the two after the cats.

CobraClone98 · 09-26-2002

do this only if you live in an area were you can drive around with 2 cats.

Vortex · 09-26-2002

Quote:

(he got addicted somehow)

SOMEHOW?????

Glen · 09-28-2002

Check around on the 02 sensors. You should be able to find them for no more then $40 each, if memory serves me correctly.

I don't know which state you live in, but all of this is emissions related and could be under warranty. I can't recall the warranty period for emissions parts and varies by state. but at least 5 years, maybe 7 years. Thats from the date the car was first purchased, not manufacturer year. Worth a check.

Bethy83a · 06-28-2009

Need help. Just bought a 1998 V-6 Ford Mustang convertible. Runs great. CEL came on after first gas refill. Disconnected battery and light went out. Refilled gas, CEL on again. Tried Super Octane Gas (no response). Replaced battery, air filter and CEL light out after next gas refill. Came on about 30 minutes later and is still on. Also driver's side mirror lamp went off -- it had been working before. Any advice. Thanks. Beth.

P.S. odometer at 60,000 miles. Rear-view mirror light has begun flickering oh so slightly.

Bethy83a · 06-28-2009

So far, back leak has not gotten into trunk and I just bail water out with a cup. Can back window and top cover be weatherstripped? Any help appreciated.

Beth

shinerstang · 06-28-2009

Quote:

Originally Posted by Bethy83a

Need help. Just bought a 1998 V-6 Ford Mustang convertible. Runs great. CEL came on after first gas refill. Disconnected battery and light went out. Refilled gas, CEL on again. Tried Super Octane Gas (no response). Replaced battery, air filter and CEL light out after next gas refill. Came on about 30 minutes later and is still on. Also driver's side mirror lamp went off -- it had been working before. Any advice. Thanks. Beth.

P.S. odometer at 60,000 miles. Rear-view mirror light has begun flickering oh so slightly.

Please go to advance or autozone so they can pull the code for free. There is no sense in guessing what it is unless you have the exact code......