New 'Y' pipe causing 02 sensor problems

[mimi94SHO]

Hi everyone! I'm new and finally found out about this forum through another forum. I have a 1994 fully loaded 3.2L SHO now with 95k miles on her. I have the check engine light on ever since I had my stainless steel "Y" downpipe w/free flow cats put on from Ford Specialties. I had a local shop check it out and determined it was the o2 sensors which makes sense since they are connected to the Y pipe and had them replaced with aftermarket ones. Well the same check engine code keeps coming back and this time I took it to the stealership and they charged me an arm and a leg to run diagnostics and determined that it is the 02 sensors again. So I had them replaced with the correct oem ones. Well eventually the same code came back again. I'm not going to replace them every few weeks since the o2 sensors are expensive. Anyway, I just need to find a professional I can take it to out here in Minnesota to figure out why this downpipe causes the o2 sensor problems. Are there different sensors I can use the same way spark plugs are used when going to a colder or hotter plug? I've been dealing with the check engine light a few years now which seems to make the car run richer causing less power. Car only dynos with 167 whp with mods such as 70mm maf, K&N drop in filter, "Y" pipe w/free flow cats, Dynomax cat-back exaust, SuperChips chip and removed the restrictive cone in the fender. So if anyone has had a simular problem please let me know what was done to get it resolved. I'm thinking the car is running rich which may be causing the o2's to go bad. I'm bringing my car to the PRO-TECH shop tomorrow and hopefully someone is competent enough to figure this out. Like I said, it only started after the new pipe with free flow cats was put on. Thanks, Neal

<small>[ December 14, 2003, 12:42 PM: Message edited by: mimi94SHO ]</small>

 

[Shuey]

did u clear the codes after the O2s were replaced?

 

[mimi94SHO]

Shuey:
did u clear the codes after the O2s were replaced?

Yes, the shops apparently clear the codes, car runs fine for a week or 2 then code comes back....

<small>[ December 14, 2003, 05:40 PM: Message edited by: mimi94SHO ]</small>

 

[rangerj]

mimi,

Here are some thoughts regarding your problem. I do not know what code or codes you are getting regarding O-2 sensors. There are several codes that could be stored in the ECM regarding the O-2 sensors, but that does NOT mean that the O-2 sensor is faulty.

The O-2 sensor could be reporting a rich or a lean condition and not "switching" because the engine is ACTUALLY running rich or lean. For you to go through so many O-2 sensors in such a short period of time defies all logic, and astronomical odds.

If your Check Engine light is on again, you can get the codes checked for free at an Auto Zone parts store. If you are getting O-2 sensor codes let us know what the codes are. Then maybe we can offer some suggestions as to where to look for your problem.

Somewhere in all those aftermarket "MODS" something is not compatable with the rest of the system, or it was not installed correctly. rangerj

 

[projectSHO89]

Chances are, neither the O2 sensors or the Y-pipe are the problem anyway given the details you have provided.

It is imperative that you post the exact codes you are receiving along with details as to what Y-pipe was installed.

Steve

 

[revhardSHO]

you can run the codes yourself yaknow. All you need is a paper clip and how to use the "search" function.

 

[mimi94SHO]

The very last mod I did was the Y pipe and the check engine light came on immediately after installation. No codes beforehand. I'll get all the codes Monday and post them. Thanks everyone.

<small>[ December 14, 2003, 10:56 PM: Message edited by: mimi94SHO ]</small>

 

[mimi94SHO]

Well I had my car checked out today and the codes were 124 & 172. Replaced the throttle position sensor and rear O2 sensor (same O2 replaced twice previously). So the real test will be to patiently wait a few weeks again and see if any codes come back. At least I have a 1 year warranty on the O2 sensor. shrug

<small>[ December 16, 2003, 07:45 AM: Message edited by: mimi94SHO ]</small>