Honestly is sounds like you have a feedback problem with your O2s. However, try this before trying to tackle the O2 troubleshooting...disconnect your MAF and see how the car runs with it disconnected. By disconnecting, I mean unplug it, not remove the MAF

Also, check to see if your engine temp reads steady. A broken engine temp sensor plug will cause your engine temp readings to appear to fluctuate and the PCM will comply and adjust fueling to compensate.

If both of those work, you'll need to plug into your PCM and monitor your O2 voltages, and/or just replace your O2 adapter (if you are using the rears in the front location). I suspect your O2 readings are very low <500 mv, thus causing the PCM to dump more fuel in to bring them up.

 

I've tried the MAF sensor disconnect while its running..no change...the tuners also swapped out different MAF sensors, TPS sensors (& entire throttle body)..the map sensor is working correctly also..

engine temps are normal and steady, as are the rest of the indicators & gauges on the DIC...

I am using 02 extensions, but I swapped the extensions with the sensors at the same time (new 02 sensors).

I don't have anything to monitor from the ODB port to get the sensor voltages...

maybe it's time to invest in hp tuners or something....

 

Is it safe to assume the tuner took the cats out of the ECM?

Anyone know if getting the right O2 connector on the LEFT O2 sensor and vice versa would cause this? I seem to remember a post about something like this but can't find it. Apparently it is not that hard to get the connectors switched and cause a problem.

Need some of the super sleuths on this forum to jump in here.

Charlie

 

yes, tuner turned off rear 02's..

got the 02's hooked up correctly...left side plug connects to right side 02 sensor & vice versa...

 

Don't have a smiley for it but :punt I'm lost as a ball in high weeds.

Charlie

 

The front O2s should not be switched. The right side should connect to the right side wiring harness and the same for the left. The O2s point inward (driver's side points towards passenger side, but it should still connect to driver's side wiring), but they connect straight through.

 

We may have a winner.

Charlie

 

You know what???? I'm an effing R-tard!!!!

I was looking though the service manual and saw the pictures of the 02 sensor routing and had realized what i done...

Muncie...you're absolutely right!!...

I'm a dumbass!!!! thanks for all your help guys!!

 

Well how 'bout get out there, jack that bad boy up, swap those muthahs, fire that dude up and tell us what happened.

Charlie

 

One step ahead of you!!! I had already fired it up when i posted last...!!!

I still had it jacked up on blocks, but i got the engine temp up past 170F and everything was working fine!

No codes or crazy idling like before after 140F...

I'll take it out and run the **** out of it tomorrow after i route the wiring to stay off the exhaust pipes...

 

Which tuner did you take it to? I am guessing mixed up O2's is something that should be caught in few minutes.

 

See above. He had O2 sensor leads swapped.

Charlie

 

Question I would have is if tuned with crossed leads, how good is the tune? I would think the street tune would have been impossible with this setup.

 

Charlie

 

sounds a lot like the trouble I just had. If you are sure you do not have a broken plug check all the wires really good. I mean really good. If thats not the problem, did you oil your intake during all this. I did and messed up my MAF. I had a broken plug, bad wire and needed a new MAF. This was all very fun and took me a lot of beer to figure out. Good luck.

 

conley's performance did the tune www.conleyracing.com..

Funny thing about the 02 sensors...since installing the new headers, my front 02 sensors wouldn't reach..so (being a cheap bastid & not wanting to buy extenders) i decided to cut off the plugs from the longer sensors and just solder the front plugs (rectangular plug) to the longer wires.

when i installed the sensors, i kept thinking of how the rear sensors were crossed and did the same for these (Wrong!!!!!)

Well, it drove like ****, so i just thought it was a tuning issue (since this is my first time to cam anything)

When i took it to conley's they told me both 02's weren't working and that they need to buy new 02's & extensions.

well guess what!!! the 'professionals' did the same thing i did and hooked the new ones up wrong like I had it....the car wasn't running right and he couldn't figure it out after 3 weeks, so i decided to take it home anyways and fix it myself....But he assured me that the tune is in the pcm and once whatever problem is fixed then the tune will be right....

Oh I would have a dyno graph to post, but I was so pissed that i threw it away..Why you ask???? because it was a graph of HP vs time...??? It didn't even show torque or rpm because he said he couldn't get an rpm signal from my plug wires. when i asked how he tuned it then, he said an rpm signal was being fed to the laptop from the ODBII port.

It showed a lowly 400 peak hp (don't ask me how you can get that without torque or rpm) from a mustang dyno.

Is it the right tune? i have no clue...since it was tuned with reversed 02's...