Need some help here guys. Back story on car, owned about 5 years, had a 2.3 whipple when I bought it with twin GT pumps and 60 lb injectors. Shortly after I bought it I added a Fore hat, dual fpdm's with upgraded harness. Car has run flawless up till I replaced clutch this spring. When I had the exhaust off I had the down pipes and X pipe ceramic coated. After install I ran the car about 20 mi. And I got a CEL. The codes said bad oxygen sensor, one rich and one lean. Car had a slight stumble at 2500 rpm but seemed to run good otherwise. Being a new clutch I didn't run car hard. They were the upstream sensors that showed bad. Car has hi flow cats on it. So I thought maybe I crossed the sensors during install. Switch them and threw a CEL within 10 miles. Went ahead and clean MAF, replaced FRPS and unhooked battery. Also replaced the upstream sensors with new Ford ones. Now when I start car it runs flawless the first 3-4 minutes of idle. Then it drops about two hundred RPM's and runs rough and starts blowing black smoke out of both pipes. No CEL but I've only driven car about 10 miles. Runs good after 2500 rpm stumble. I went ahead and changed the downstream sensors and same thing. I'm wondering if the ceramic coating is causing a higher heat buildup in the exhaust causing the sensors to release more fuel? Out of ideas at this point. I've never messed with my Sct hand held other than look at the parameters to see if there was anything in there to adjust the heat range of the sensors or not and there wasn't. I also started running Torco last year and have about three tanks run through the car. Looking for some advise I really want to enjoy my car again but I'm afraid to even run it in this condition!
Cobra running pig rich at idle
- Thread starter xchamp
- Start date
The harness is correct to each side. I get no CEL's with the new sensors, and both pipes are rich. Idles great for 3 to 4 minutes then loads up and black smoke from both pipes.
Do you recall the code numyers you got..
There really isn't a code for bad o2..
The 02 has many functions so it also has 40 different codes..
Very important to write down code numbers before resetting pcm..
Mine being stock..o2 or emission codes are what I get..
O2s were the most..
The main pc version of manual has test for codes..
I had many o2 codes after reinstall of heads..
Manual helped me find issue..
Question
.were the coils ever changed?
There really isn't a code for bad o2..
The 02 has many functions so it also has 40 different codes..
Very important to write down code numbers before resetting pcm..
Mine being stock..o2 or emission codes are what I get..
O2s were the most..
The main pc version of manual has test for codes..
I had many o2 codes after reinstall of heads..
Manual helped me find issue..
Question
.were the coils ever changed?
P2196, P2197. O2 sensor signal biased/stuck rich bank one sensor one. Stuck lean bank 2 sensor one. That was on the initial CEL. Car idled fine at this point. Changed all 4 sensors and now there is no code and car idles perfect for 3 to 4 minutes then both pipes start blowing black smoke. And no I've never changed coil packs.
You might need to drive it for awhile.
The pcm when reset defaults to factory setting on fuel trim..
Yours being 60lbs vs 39 could be why..
Just a thought. .
You might have tilted engine enough to pull inlet tube from throttle body which might have sent code..
Vacuum leak..
If the car was fine before, it's not the tune. Even though you only did exhaust, your culprit might not be the sensors and could be something else.
Bad or stuck injector?
Have you tried to datalog it?
Keep looking, you will find it.
Bad or stuck injector?
Have you tried to datalog it?
Keep looking, you will find it.
You can use your hand held to read fuel trim
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