New Exhaust, CEL Light Codes, HELP!

New Exhaust, CEL Light Codes, HELP! UPDATE: NEW PICS

Hello, I posted a week back or so about my new exhaust set up and how the Check Engine Light came on (Previous Post CLICK). I recently installed MAC LT Headers, MAC O/R Prochamber, and Magnapacks. Also put in 02 Extensions and Steeda MIL's. All on 2002 GT, 5-speed, no engine mods.

Check Engine light came on, and car was acting strange a few times when cold cranking. Would idle fine, but when I put it into first it felt like it ran out of gas and wanted to shut off. Pull over, let it sit 5 minutes, revved a few times and the car was fine. This happened to me 3 times, each time after the car had sat for the night. But, hasn't happened in a few days now.

But anyway, I went to Autozone today and had them read the codes my car was throwing.

It has two trouble codes:

P0135 AND P1131.

P0135 - Upstream Heated Oxygen Sensor Heater circuit fault - Bank No. 1.

P1131 - Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1.

On the scanner at A.Zone for P1131 it said Fuel Air Metering. I got the above descriptions from the sticky.

So what exactly do these codes mean in English? And what do I need to do to fix them??

Thank you for your help!
 
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Thanks 4 the responses. Yes, I have disconnected the battery several times for a few hours and the light keeps coming back on.

I did not do the install, so Im not to sure what to look for. The harness was extended using 24" extensions from Mustang Tuning:

View attachment 508859

How do I check the wiring, what am I looking for, and where would it be? Up front towards the headers or on the midpipe? What should I do, unplug then plug it back in???

Thanks!

And is it both sides or just one? What does Bank 1 mean?
 
UPDATE - Pics!

Ok, so I jacked up my car on both sides and took some shots. I didn't want to crawl under, wasn't sure if it was safe with just a jack, and I burned my fingers a few times anyways, the car was too hot. So I didnt unplug and reconnect anything. I wanted to get your opinions of what to do before I mess with stuff tommorow.

Here are some shots:

I zoomed in on this wire that was coming out of the header on the driver side. It looks like some wires are coming out of the green sleeve. Is it suppose to be like that, or is it a bad connection?? Also, which wire is this exactly?

headerwire36kd.jpg


Here are two shots of the MILs looking over from the passenger side of the car:

passsidemils24pw.jpg


In this second shot, it looks like the connector is not firmly pushed into the purple cap, or is this how it should look?

passsidepurplecap3ru.jpg


Here are two shots from under the car looking in from the drivers side:

driversideview2ym.jpg


driverside33cr.jpg


So, does anything look wrong or loose? And also can someone explain what each wire is? The MILs I can see are in the middle. What are the purple and blue connectors, are these the 02 sensors? And if so, which is driver and which is pasenger?

Then where are they hooking up to? What is that purple cap towards the back of the MILs clipping them to?

Thanks for the help guys! I want to know what I am doing when I go under 2maro.
 

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When you get up there tomorrow, check the front passenger side o2 sensor wiring. Just check everything, the extensions, and the actual wiring to the sensor itself. It sounds like something is probably loose. I had a similar problem when I did mine, only it was on the drivers side.. I got P0059.. it turned out some of my connections had broken loose when I reconnected the sensor. Don't bother replacing the o2 sensor.. it's a wiring issue.
 
There are 2 reasons (besides a bad sensor) that the light will be on.

1 is the MILS

2 is one of the wires in the harness came loose.

I drove around for years not knowing why my CEL came on, I fiunally looked up the harness that goes to the o2 sensor and tested it with a multimeter and bam! found the problem. There was no signal going to the sensor.

Test the wiring. Hope it helps. :nice: