Ok, sorry if this is long winded, but I feel the need to explain in detail so someone can help the best they can.
Installed my dual exhaust, after the cats, did not mess with the cats or o2 sensors. About 1,000 miles after installation, my check engine light came on. I took it to the dealership, the error code was P0153, bank 1, sensor 1. The dealership replaced the o2 sensor and all was well. Till 300 miles later when my check engine light came on again. Had the codes read and got the same P0153 code, PLUS P0300 Engine(multiple cylinder) misfire. That scared the crap out of me. Took it to the dealership, they said the EGR Valve was stuck open, throwing the code. They ordered the parts and the next day I dropped it off, they replaced the EGR valve and the o2 sensor. They told me they ran a diagnostic and that fixed the problem.
Fast forward to TODAY, one day later, and less the 100 miles later, and my check engine light comes on AGAIN! Stopped by autozone on my way to work, had the code read, you guessed it, P0153.
At this point I am really frustrated, have lost all faith in the dealership, and ready to drive the car into a tree so the insurance can pay for it and I get another one. Ok, maybe that is to extreme.
Does anyone have ANY clue as to what the problem is? How to fix it? What my next step should be? Anything would help.
Well, it does seem unlikely as it's not exhaust related, but it could be a coincidence. The DTC does mention MAF sensor so get them to clean it or have a go yourself. Good luck
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www.mkeeler.com/mustang/ Minority group member - Got three pedals and I like going round corners
Just spitballing here.. In my personal experience I've seen O2's go bad for a couple of reasons - repeated use of crap gas, or the A/F ratio being off.. you make no mention of any other mods other than exhaust - so is that all you have? No tune, etc? On the V6's I'm not sure if just exhaust requires a retune, but I would guess that it may. And you're sure you've got no exhaust leaks on the bank that the O2 keeps going bad on? (The O2 may see it as an overly lean due to the extra air.) Also - the EGR being stuck open would act like a lean condition on cold start.. either way, it sounds like you're issues started with the exhaust install, so go back and check all your work.
Just spitballing here.. In my personal experience I've seen O2's go bad for a couple of reasons - repeated use of crap gas, or the A/F ratio being off.. you make no mention of any other mods other than exhaust - so is that all you have? No tune, etc? On the V6's I'm not sure if just exhaust requires a retune, but I would guess that it may. And you're sure you've got no exhaust leaks on the bank that the O2 keeps going bad on? (The O2 may see it as an overly lean due to the extra air.) Also - the EGR being stuck open would act like a lean condition on cold start.. either way, it sounds like you're issues started with the exhaust install, so go back and check all your work.
No other mods besides the exhaust. It's not the gas, I fill up at the same station everytime, never has a problem. I had the exhaust checked, once by me, and a second by a shop, no leaks were found. I don't think the exhaust requires a tune, there are plenty of members here that have this exhaust with no tune, and have no problems. The car is losing power at lower RPM's, like it is bogging down, but once the RPM's get above 2500, it runs fine.
You could get a CAI and tune and have the rear O2 sensors turned off.
It's not the rear O2 sensors giving the problem, it's sensor on the drivers side, before the cats, which is why, well my hunch is, that my exhaust is NOT causing the problem. But, I am not an expert, which is why I turned here, cause there seem to be a few of those around here
. The car is losing power at lower RPM's, like it is bogging down, but once the RPM's get above 2500, it runs fine.
This is likely because the O2 sensor is shot and the car is loading up on fuel down that low...
Try something for me. Go out, and from a stop do a full throttle run up to the speed limit. Pay attention to the low end of your power curve. Does it still seem sluggish at WOT or is it just at part throttle.
Second question... did you relocate the O2 sensors at all from their stock location?
My feeling is that the exhaust is not an issue here and what your seeing is comging from problems in the EGR. Chances are that the EGR going bad killed the first sensor.. then the second time when the EGR was replaced, the damage had already been done to the second O2 sensor, and it was just a matter of time before it died...
That being said, take it back to the dealership and give them another shot at it. It sounds like they are trying in good faith to fix your issue. Sometimes it just takes a time or three to get it figured fully out.
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"Vera" '07 GT. Manual, 3.55's, Spohn Adj LCA's, Hurst Shifter, GT 500 Rear and chin spoilers, GTA's, Steeda UDP, Roush rear springs, ProFab CAI #6, BBK Shorties
"Dyno's Rarely Lie, but E.T.'s and Trap speed say so much more."
. The car is losing power at lower RPM's, like it is bogging down, but once the RPM's get above 2500, it runs fine.
This is likely because the O2 sensor is shot and the car is loading up on fuel down that low...
Try something for me. Go out, and from a stop do a full throttle run up to the speed limit. Pay attention to the low end of your power curve. Does it still seem sluggish at WOT or is it just at part throttle.
Second question... did you relocate the O2 sensors at all from their stock location?
My feeling is that the exhaust is not an issue here and what your seeing is comging from problems in the EGR. Chances are that the EGR going bad killed the first sensor.. then the second time when the EGR was replaced, the damage had already been done to the second O2 sensor, and it was just a matter of time before it died...
That being said, take it back to the dealership and give them another shot at it. It sounds like they are trying in good faith to fix your issue. Sometimes it just takes a time or three to get it figured fully out.
Thanks for the response GT Bob.
It does not seem very sluggish at WOT, but under normal driving, seems to have some hesitation, and to get rid of it, I have to step on it, then it kinds "jumps" to pick up the throttle, if you know what I mean.
Did not relocate any O2 sensors from the stock locations, never touched them.
I am taking it back to the dealer on Monday, it is just very frustrating. Seems all these problems came about after installing my duals, but everyone tells me(including the dealer) that they are not the problem.
If you have any Ideas, let me know, I will update Monday afternoon after the dealer looks at it again.
Well, hopefully 3rd time is a charm. Dealer had it all day today, said they were going over it with a fine toothed comb. They stated that after they replaced the EGR valve, the O2 Sensor they were sent from parts was defective, so they replace that today, ran a check. Drove the car for about 15 minutes, brought it back, and ran the check again, and all went well.
Hopefully this fixed the problem, keeping my fingers crossed.
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