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Help! Im at my wits end!!! 2003 Mustang GT recurring P0133 and P0153

  • Thread starter Thread starter Warhorse85
  • Start date Start date Jun 17, 2023
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Warhorse85

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Jun 17, 2023
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Jun 21, 2023
#21
  • Jun 21, 2023
  • #21
alwayshi said:
Mehhh. If it ran fine, you don’t HAVE to. However, it may take a longer period for the PCM to relearn the values rather than starting fresh. Up to you. It’s not a must-do
Click to expand...
Ok. Just for s and giggles, I'll unplug it when I get home and let it sit then let it idle
 

Noobz347

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#22
  • Jun 21, 2023
  • #22
If you cleared the codes with a scanner then you don't need to do anything else. The 'CAM'/adaptive settings will do their own thing so long as there is nothing mechanical that is operating outside of the EEC's ability to adjust. I don't know what the specific number is for your particular EEC but generally, it is around 15% of the baseline (rule of thumb, so to speak).
 
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Warhorse85

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Jun 21, 2023
#23
  • Jun 21, 2023
  • #23
Noobz347 said:
If you cleared the codes with a scanner then you don't need to do anything else. The 'CAM'/adaptive settings will do their own thing so long as there is nothing mechanical that is operating outside of the EEC's ability to adjust. I don't know what the specific number is for your particular EEC but generally, it is around 15% of the baseline (rule of thumb, so to speak).
Click to expand...
So for the hell of it I disconnected the battery for 30 minutes and then let it idle. It surged for a few minutes on first startup then evened out. I did end up putting the factory throttle body back on and started the car back up. Now I have different codes that popped up. P1131, P1151 and P1152
 
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Yel2002GTAuto

Active Member
Sep 26, 2022
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Jun 22, 2023
#24
  • Jun 22, 2023
  • #24
If you do disconnect the battery....zip tie the positive and negative terminals together....this will drain and residual charge in any capacitor...usually 4 hrs will reset everything....but I like to do it overnight...
 
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Warhorse85

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Jun 22, 2023
#25
  • Jun 22, 2023
  • #25
Yel2002GTAuto said:
If you do disconnect the battery....zip tie the positive and negative terminals together....this will drain and residual charge in any capacitor...usually 4 hrs will reset everything....but I like to do it overnight...
Click to expand...
So after installing the factory throttle body I had a lean and rich code show up for the drivers side O2 sensor
 

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Yel2002GTAuto

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Sep 26, 2022
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Jun 22, 2023
#26
  • Jun 22, 2023
  • #26
I would say you really need to tune it..your running about 15 to 20% more air through your engine now...your factory tune is way off compared to the mods your car has...if it is running fine and just throwing 02 sensor codes it is the tune..
 
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Yel2002GTAuto

Active Member
Sep 26, 2022
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Jun 22, 2023
#27
  • Jun 22, 2023
  • #27
These cars are so sensitive to timing and low end fuel trims that simple bolt ons can drastically effect the tune..
 
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Warhorse85

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Jun 17, 2023
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Jun 22, 2023
#28
  • Jun 22, 2023
  • #28
Yel2002GTAuto said:
These cars are so sensitive to timing and low end fuel trims that simple bolt ons can drastically effect the tune..
Click to expand...
I think I have a vacuum leak. I noticed both pcv valves are very oily around them. Plus my car only idles at about 800 rpms on first startup in the morning after sitting all night
 
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Yel2002GTAuto

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Sep 26, 2022
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Jun 23, 2023
#29
  • Jun 23, 2023
  • #29
A couple other thoughts... do you have O2 Extenders or were they spliced and extended for the headers.... Sometimes they need to be mounted away from the headers as they can melt and then have a bare wire or the wire touched the header .... Is the car surging? this will be more of a vacuum line issue if so.... Does the car have cams or just full bolt ons?

During start up the car will idle 400-500 rpm higher at idle until its starts to receive signal from the thermostat.... then as the tables rises in signal it will adjust the 02s and other idle sensor calibrations and lower the idle....

I can't remember is you noted the EGR tube was hooked up or not.... if that is case then if the EGR Tube is blocked then it should be turned off inside the tune/computer ... or you could have signal feedback issues...

Also, try replacing the thermostat or thermostat sensor... sometimes those just go out and send a bad signal..
 
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Warhorse85

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Jun 17, 2023
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Jun 23, 2023
#30
  • Jun 23, 2023
  • #30
Yel2002GTAuto said:
A couple other thoughts... do you have O2 Extenders or were they spliced and extended for the headers.... Sometimes they need to be mounted away from the headers as they can melt and then have a bare wire or the wire touched the header .... Is the car surging? this will be more of a vacuum line issue if so.... Does the car have cams or just full bolt ons?

During start up the car will idle 400-500 rpm higher at idle until its starts to receive signal from the thermostat.... then as the tables rises in signal it will adjust the 02s and other idle sensor calibrations and lower the idle....

I can't remember is you noted the EGR tube was hooked up or not.... if that is case then if the EGR Tube is blocked then it should be turned off inside the tune/computer ... or you could have signal feedback issues...

Also, try replacing the thermostat or thermostat sensor... sometimes those just go out and send a bad signal..
Click to expand...
So on first startup after sitting overnight it idles around 850 rpms. It surged on me a couple of times but only for about 2 minutes and then evened out. Here is a list of the parts I've replaced IN THE PAST YEAR....IAC, ERG VALVE, MAF SENSOR, ALL 4 O2 SENSORS, AND COOLANT TEMP SENSOR. I JUST ORDERED A NEW PCV VALVE AS WELL. I REPLACED THE EGR TUBE ABOUT 5 YEARS AGO. COULD HAVING THE RUBBER EGR HOSES COMING FROM THE TUBE TO THE DPFE SENSOR NOT IN THE CORRECT POSITION CAUSE AN ISSUE?
 
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Yel2002GTAuto

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Sep 26, 2022
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Jun 24, 2023
#31
  • Jun 24, 2023
  • #31
Yes, that could for EGR valve...you noted you had a hand held code reader...does it data log or read live data...you could connect it before start up and read the temps at startup and monitor until it gets up to temp...see how much the coolant temp reads before and after...also check 02s before and after...as long as things look like they are changing correctly you should be good...if not it's a place to start..
 
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Warhorse85

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Jun 25, 2023
#32
  • Jun 25, 2023
  • #32
Yel2002GTAuto said:
Yes, that could for EGR valve...you noted you had a hand held code reader...does it data log or read live data...you could connect it before start up and read the temps at startup and monitor until it gets up to temp...see how much the coolant temp reads before and after...also check 02s before and after...as long as things look like they are changing correctly you should be good...if not it's a place to start..
Click to expand...
So I may have found some possible vacuum leaks between the intake tube and the throttle body. I replaced all the large vacuum lines and the PCV valve. Still no high idle at first startup but that may be because it's too warm out. This all started 2 years ago when I had the clutch and flywheel replaced and had the spark plugs replaced as well. I did however had the plugs gapped a little smaller because I was planning on having the car tuned and so I was instructed to gap the plugs smaller. I had a lightweight flywheel installed with the new clutch.
 

Noobz347

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#33
  • Jun 26, 2023
  • #33
Sounds like you are making progress and getting all of the mechanical gremlins worked out.
 
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Yel2002GTAuto

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Sep 26, 2022
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Jul 12, 2023
#34
  • Jul 12, 2023
  • #34
So did the vacuum leaks you fixed address the issue? Just curious on your results...
 
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Warhorse85

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Jul 14, 2023
#35
  • Jul 14, 2023
  • #35
Yel2002GTAuto said:
So did the vacuum leaks you fixed address the issue? Just curious on your results...
Click to expand...
So I replaced all the large vacuum lines between the intake tube and throttle body. Check engine light was still coming on. I managed to clear the code with my scanner while driving and got all the monitors to set so I immediately went and got it inspected. I was told to leave it running during the emissions inspection and it passed. I shut the car off after the inspection to go pay for it and then I started it and drove out of the shop and before I made it to the road to leave the check engine light came back on with 2 different codes
 

Noobz347

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#36
  • Jul 14, 2023
  • #36
Well, it does sound like you're making progress at least.

What codes do you have now?
 
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Warhorse85

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Jul 14, 2023
#37
  • Jul 14, 2023
  • #37
Noobz347 said:
Well, it does sound like you're making progress at least.

What codes do you have now?
Click to expand...
I don't remember off the top of my head but I believe they are bank 1 and 2 rich codes
 
Y

Yel2002GTAuto

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Sep 26, 2022
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#38
  • Jul 14, 2023
  • #38
Glad you got through inspection.... it definately is the tune at this point....almost always after modding a car to you level the A/Fs and time needs to compliment you build...trust me you will be happy...
 
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Warhorse85

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Jun 17, 2023
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Jul 15, 2023
#39
  • Jul 15, 2023
  • #39
Yel2002GTAuto said:
Glad you got through inspection.... it definately is the tune at this point....almost always after modding a car to you level the A/Fs and time needs to compliment you build...trust me you will be happy...
Click to expand...
So I was wrong about the codes. It is still the original codes P0131 and P0153
 
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grewalv8

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Dec 8, 2024
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Dec 8, 2024
#40
  • Dec 8, 2024
  • #40
Did you end up figuring it out?
 
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