P0243 code after header install, HELP NEEDED!!

[TP 112]

Let me say before I did anything the car ran perfect with no issues at all. The only thing I did was install long tube headers and off road X- pipe. I unplugged the battery before starting this project. Did the swap plugged battery back up and started the car. Now I'm getting this code p0243 and my afr gauge is pegged out to 16 on the gauge and idling rough. I have checked everything several times, unloaded and reloaded the tune with that not helping. Changed frps/fpdm and that did nothing, fuel pressure is good on my gauge also. Checked all the plugs and they look good also. I am hoping that just unplugging the battery for a day and plugging it back up didn't cause me to mess up the tune in any way. The grounds are good also. The car had a mid length/x-pipe set up before changing anything. On initial start up it will run good like its in start up mode for a few minutes, all reads great on the afr gauge also, and then its like the computer is telling it something and I can feel it instantly and then the car goes into very lean and rough idle conditions. I have checked everything and I am at a loss. The car is a egr delete car and all has been turned off in the tune for a good 8 month's also. I haven't driven the car at all for fear of burning up the engine. Any info will be a great help, Thanks!

 

[MG0h3]

So you went from a NON EGR NON catted setup to just a longtube setup? No change to cats, EGR, or O2 sensors?

Double check your work. Sure an O2 didnt get just half plugged in or something? If it ran right before and it doesnt now, you are likely the culprit. I usually SMH after chasing all kinds of weird diagnosis streams and then realize it was just something I messed up during a mod.

It also sounds like the car is in open loop/running correctly and then is reaching operating temp/closed loop and running like crap.

Ok so I just googled that code. Looks like a code related to the bypass valve. Sure you didnt change anything else?

 

[hotcobra03]

Is this the only code appearing?

 

[TP 112]

yes its the only code I am getting. Changed nothing else all egr deleted and always no cats on both set ups. I did change all the O2 sensors with new ones and extensions also. I am going to unplug and re-plug all the O2 sensors now, that's all I haven't done yet, but they clicked good sounding. Thanks!

 

[JuStAkId]

yes its the only code I am getting. Changed nothing else all egr deleted and always no cats on both set ups. I did change all the O2 sensors with new ones and extensions also. I am going to unplug and re-plug all the O2 sensors now, that's all I haven't done yet, but they clicked good sounding. Thanks!

Might be a dumb thing but did you buy the right o2 sensors? Did you maybe mix up and put rear o2's (designed to monitor exhaust gasses after the cats) in the front o2's?

 

[hotcobra03]

Ive had this code before..years ago..still have new sensor. .

trying hard to recall issue...and cure..

I to have exhaust open all o2s on ..

Im thinking vacuum issue..I had replaced my full vacuum hose harness back then also..I had some issues with restrictions and cracks..

these hoses just break looking at them and now aged just leaning on them is enough..

I had pulled complete harness and opened it and inspected all hoses..

not sure how you did your job..I was all over engine doing mine

 

[TP 112]

The sensors are in the correct spots. I do believe that the rear sensors were turned off in the tune I got from VMP when I bought the tuner and tune from them. I did buy the correct sensors also. All the vacuum lines look great and are hooked up. I unplugged and re-plugged all sensors back in but didn't change anything.

 

[hotcobra03]

I would drive car and see if any more codes appear..

this sensor and code isnt going to hurt anything..just drive normal

...

ive delt with o2 codes on mine alot..as I learned this car and using factory manual pin point tests for codes..

 

[TP 112]

these are the O2 sensors parts #'s I replaced with 3 of them are bosh # 15717 2 upstream and 1 on right rear and 1 is bosh # 15716 which is rear left. I did take the car down the road but it stayed into lean and feels sluggish. Could I have the wrong sensors for the car ?? Are these wrong if so I need #'s please. This is what the parts store calls for the car though. I am coming to the conclusion that this is the only other change made that would be related to my lean condition. Maybe I need to replace with all ford sensors??

 

[hotcobra03]

vacuum leak will cause lean..

stick with code....here is some copy and paste from manual on po243...

just read it.codes come from electric issues..this sensor works also by vacuum yet test have no vacuum test mentioned....except last step


P0243 - Supercharger (Boost) Bypass Solenoid Circuit Malfunction The PCM monitors the supercharger (boost) bypass (SCB) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified SCB solenoid duty cycle (100% or 0%) by PCM command. VPWR circuit open to SCB solenoid
SCB solenoid circuit shorted to PWR GND or CHASSIS GND
Damaged SCB solenoid
SCB solenoid circuit open
SCB solenoid circuit shorted to VPWR
Damaged PCM
Disconnect SCB solenoid. Connect test lamp to SCB solenoid harness connector. Cycle SCB driver in PCM by Output Test Mode. Test lamp cycle on and off - SCB solenoid is suspect. Test lamp always on - SCB signal short in harness or PCM. Test always off - SCB signal or VPWR open in harness or PCM





start kj6

2003 PCED OBD SECTION 5: Pinpoint Tests
Procedure revision date: 08/19/2002

--------------------------------------------------------------------------------
KJ: Supercharge Bypass Control KJ: Introduction

--------------------------------------------------------------------------------

KJ1 DTC P0234: CHECK FOR OTHER DTCS
Note: The supercharger will be bypassed when the brake is on and the throttle is depressed in the wide open throttle position. This is called brake torque and the engine torque is too high.

Check that the engine has not been subjected to brake torque causing the P0234.
Drive the vehicle for 10 to 15 minutes with the engine exceeding 2,000 rpm and the engine temperature stabilizing.
No Starts:
GO to A1 .
For Stalls:
Return to Section 3 , Symptom Charts.
Return to repair area and check that upper radiator hose is hot and pressurized.
Rerun Quick Test and retrieve KOER and continuous and retrieve DTCs.
Are any other KOEO, KOER and Continuous Memory DTCs present with the KOER or Continuous Memory P0234?
Yes No
KEY OFF. GO to Section 4, Powertrain Diagnostic Trouble Code (DTC) Charts , for Pinpoint Test direction and REPAIR DTCs. GO to KJ2 .

KJ2 CHECK SCAN TOOL PIDS FOR CAUSES OF OVERBOOST CONDITION
Key on, engine running.
Access IAT2, TFT (5.4L SC only) and RPM PIDs.
Observe the PIDs for values exceeding the following limits:
Intake air temperature (downstream), IAT2 PID greater than 230°F.
Transmission fluid temperature, TFT PID greater than 275°F (5.4L SC only).
Do any of the above PIDs exceed the limit?
Yes No
For IAT2:

CHECK for low fluid level in Intercooler System. CHECK for cracked intercooler lines. REPAIR as necessary.

For TFT (5.4L only):

CHECK for low transmission fluid level. REFER to Automatic Transmission Section 307 in the Workshop Manual for fluid changes. GO to KJ3 .

KJ3 CHECK FOR LOW SPEED FUEL PUMP RELAY NOT SWITCHING
Key on, engine running.
Access LFPF PID.
Is a fault indicated on the low speed fuel pump (FP) output?
Yes No
KEY OFF. GO to Section 4, Powertrain Diagnostic Trouble Code (DTC) Charts for diagnostic direction following DTC P1232. CHECK for indications of engine knock while driving the vehicle. REPAIR as necessary. If OK, indicate to vehicle owner that transmission damage will occur upon brake torque (reference: GO to KJ1 ). Otherwise, unable to determine cause of overboost condition at this time.

KJ6 DTC P0243: CHECK SUPERCHARGER (BOOST) BYPASS SOLENOID OUTPUT
Key off.
Disconnect supercharger (boost) bypass (SCB) solenoid.
Connect a non-powered test lamp between SCB and VPWR circuits at the SCB solenoid harness connector.
Key on, engine off.
Attempt to close and open SCB solenoid driver in PCM by accessing Output Test Mode or scan tool.
While observing the test lamp, command the PCM outputs on and off.
Does the test lamp cycle on and off (light up and turn off)?
Yes No
KEY OFF. GO to KJ7 . For test lamp always off :

GO to KJ8 .

For test lamp always on :

KEY OFF. GO to KJ11 .

KJ7 CHECK SCB SOLENOID RESISTANCE
Measure SCB solenoid resistance.
Is resistance between 68 and 78 ohms?
Yes No
CHECK for damaged vacuum hoses between engine intake manifold and SCB solenoid. CHECK for vacuum reservoir assembly leaks. REPAIR or REPLACE as necessary. If OK, GO to Z1 for intermittent diagnosis. REPLACE damaged SCB solenoid.

KJ8 CHECK FOR OPEN VPWR CIRCUIT BETWEEN SCB SOLENOID AND POWER RELAY
Measure voltage between VPWR circuit at the SCB solenoid harness connector and battery negative post.
Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KJ10 . KEY OFF. GO to KJ9

KJ9 CHECK VPWR CIRCUIT FOR OPEN IN HARNESS
Note: Refer to the PCM connector pin number chart in the beginning of the pinpoint test.

Disconnect PCM.
Measure resistance of VPWR circuit between PCM harness connector pin and SCB solenoid harness connector.
Is resistance less than 5.0 ohms?
Yes No
GO to KJ10 . REPAIR open circuit.

KJ10 CHECK SCB CIRCUIT FOR OPEN IN HARNESS
Measure resistance of SCB circuit between PCM harness connector pin and SCB solenoid harness connector.
Is resistance less than 5.0 ohms?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPAIR open circuit.

KJ11 CHECK SCB CIRCUIT FOR SHORT TO PWR GND IN HARNESS
Note: Refer to the PCM connector pin number chart in the beginning of this pinpoint test.

Disconnect PCM.
Disconnect scan tool from DLC.
Measure resistance between SCB circuit and multiple PWR GND circuits at the PCM harness connector.
Are all resistances greater than 10,000 ohms?
Yes No
RECONNECT scan tool. GO to KJ12 . REPAIR short circuit.

KJ12 CHECK SCB CIRCUIT FOR SHORT TO PWR OR CHASSIS GND IN HARNESS
Key on, engine off.
Measure voltage between SCB circuit at the PCM harness connector and chassis ground.
Is voltage less than 1.0 volts?
Yes No
KEY OFF. REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). KEY OFF. REPAIR short circuit to VPWR, VREF or chassis ground.

KJ13 LACK OF POWER (LOW BOOST) - CHECK VACUUM HOSES
Note: For vehicle specific vacuum hose routing, refer to the vehicle information decal located in the front of the engine compartment.

Check for holes or cracks in the vacuum hose/tube between the supercharger bypass actuator and the supercharger bypass solenoid.
Check for holes or cracks in the vacuum hose/tube between the supercharger bypass solenoid and vacuum reservoir assembly.
Check for bends or kinks in the vacuum hose/tube between the supercharger bypass actuator and the supercharger bypass solenoid.
Check for bends or kinks in the vacuum hose/tube between the supercharger bypass solenoid and vacuum reservoir assembly.
Check for disconnect hose(s) between the supercharger bypass actuator, supercharger bypass solenoid and vacuum reservior assembly.
Are any leaks (holes or cracks) or restrictions (bends or kinks) in the vacuum hose(s) present?
Yes No
REPAIR or REPLACE vacuum hose(s)/tube as necessary. RETURN to Section 3 , Symptom Chart 8 for Lack/Loss of Power.




--------------------------------------------------------------------------------

 

[hotcobra03]

my new sensor XL3V-9H465-AA is in my hand..guess I didn't need it but brought from ford when chasing code

 

[TP 112]

I went to the autozone web site and they show the 15717 sensor being for downstream. I have those upstream and 1 down stream on right rear. And their site call for 15719 for the upstream sensors. the only thing I can visually see different is the length in the wire/plugs. isn't the sensor the same just different lengths in wire/plugs?? Maybe this is the my troubles, wrong sensors in the wrong spots as stated in a prior post ?? The sensors I bought came from Oreilly store.

 

[hotcobra03]

this sensor has 3 vacuum ports..vac changes voltage signal


this tests are also tricky..it could be assuming you have already put new vac hoses on or checked by blowing into and sucking thru line to confirm clear flow both ways and no leak if sealed and pressured


o2s I wouldn't worry about but I would check harness extentions..make sure its pinned properly..they have been found to be wrong ..

rear o2s..blue plug drivers side purple on passenger

I use bosch with extended harness orielys basic

 

[JuStAkId]

Only difference between the 15717 and 15716 is the harness length. Not sure about 15719.
I have 15717 in my car (have long tubes and o2 extensions) so you have the right sensor.
What extensions do you have?

Are all the vac lines to the boost by-pass still hook upped? something might have come unplugged. That would be my next bet

 

[TP 112]

I was able to eliminate the extension on the driver side, but I have to us the one on the passenger side and all looks correct. I am going back to the engine compartment now and just double check everything . Thanks for all the help men.

 

[TP 112]

I am using the extensions that came with the kooks headers.

 

[hotcobra03]

good luck..

also to pull complete vac harness is very easy and work in hand...


on o2 wires..there are 2 white wires in harness..1 gray 1 black..use a meter on it the 1 you took off..

however you should get o2 codes if having issues with them..

pin test h for fuel control....says when testing o2s run engine at 2500 rpms for 2 mins...code should set if problem...just not sure if
171/174 will trigger that soon

 

[MG0h3]

Seems like the easiest thing would be to put the old/original O2s back in if you have them.

I suppose you could have a vacuum leak, but it doesnt seem to be an issue until the car warms up or 02s heat up? Typically if its such a large leak that you are that lean you'll end up with a surging idle or some other symptoms.

 

[TP 112]

Believe me the only reason I had to buy new ones was because those SOB's wouldn't budge. I did all I could to not have to buy any, I was pissed when I couldn't even get one of them out. Hercules must have put them in and dry also.

 

[hotcobra03]

Supercharger (Boost) Bypass Solenoid/(Thermactor Air Control Solenoid/Vacuum Valve Assembly)
The supercharger (boost) (SCB) solenoid (Figure 146) is used to control intake manifold vacuum to the vacuum bypass actuator. This part is replaced in field service diagnostics under the part name of a thermactor air control solenoid/vacuum valve assembly (part number 9H465). The PCM transmits an output signal to the SCB solenoid, thereby activating the solenoid to apply stored vacuum from the reservoir to the actuator, when an undesirable condition occurs in the engine. Once the engine condition has been corrected, the solenoid will be de-activated by the PCM, allowing engine intake manifold vacuum to control the actuator. The SCB solenoid is normally de-energized.