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Hi

I'm still having problems in solving my P1238 error. It comes back intermittendly, but always at low RPM. Here is the full Alfadiag error message :

P1238
Failed Component Code: Air control negative governor deviation
Fault Symptom: Negative governor deviation above limit
Warning Lamp Status: Warning Lamp Illuminated
Fault Test State: Test not complete for this Error.
Fault Code Storage State: Error Not Present at time of request
Event Count: 40 count
Environmental Condition One: Engine Speed: 1647.1 rpm
Environmental Condition Two: Fuel Quantity: 9.41 mm3/str
Environmental Condition Three: Accelerator Pedal: 9.8 %
Environmental Condition Four: Rail Pressure: 556.85 Bar
Environmental Condition Five: Turbo Pressure: 1011.79 mBar
Environmental Condition Six: Engine Temperature: 83.78 °C
Just a short history. Car was in a front end accident. All radiators and intercooler was replaced. Turbo hoses was replaced. Car was remapped as map was corrupted after accident.
After remap faulty turbo was replaced. The car was very sluggish after accident, and still is. Don't have the same pull as before. Also smoking a lot more than it used to. I blanked off the EGR valve recently, expecting to somewhat improve the smoking bit. That didn't help a bit.
Also the turbo whine it notiseable louder than before. Especially with the passenger window open.

Any help in decyphering this message and solving the smoking and power issues will be greatly appreciated.
 

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I make a P1238 fault to be fuel pump, though Alfadiag is rarely wrong, I think in this case it's lying, your symptoms certainly match a fuel pump snag.

P1238 Fuel Pump Secondary Circuit Malfunction
 

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can you hear the fuel pump after switching on ignition ?
 

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Discussion Starter #4
I haven't noticed if the fuel pump is audible when switching on ignition. Should it be ?
If it is the fuel pump, where does the
Failed Component Code: Air control negative governor deviation
Fault Symptom: Negative governor deviation above limit
bit come from ?
Don't know if it is related to some of my problems, but another small thing i noticed after accident is that my hot and cold idle speed swopped.
Before accident : Cold engine = higher idle speed.
Hot engine = lower idle speed.
Ater accident : Cold engine = lower idle speed
Hot engine = higher idle speed.
 

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the pump is situated in the fuel tank , if you have good hearing you can hear the pump when ignition is turned on. Have someone operate the key while you sit/laydown with you ear on the seat in the back.
 

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Discussion Starter #6
What would i learn if i can hear the pump, or not hear it for that matter ? Does it get louder or softer when failing ?
I can understand the sluggish behavior could be attibuted to a faulty fuel pump, but how would that contribute to the excessive smoking ?
 

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Discussion Starter #7
I got this from a Ford forum. Could this be aplicable to my car as well ?

P1237=Fuel Pump Secondary Circuit (Fuel Pump Driver Module)

Electronic Returnless Fuel Systems (ERFS) utilize a Fuel Pump Driver Module (FPDM) to control fuel pressure. The PCM uses a Fuel Rail Pressure Sensor (FRP) for feedback. The PCM outputs a duty cycle to the FPDM to maintain the desired fuel rail pressure. During normal operation, the PCM will output a FP duty cycle from 5% to 51%. The FPDM will run the fuel pump at twice this duty cycle, e.g. if the PCM outputs a 42% duty cycle, the FPDM will run the fuel pump at 84%. If the PCM outputs a 75% duty cycle, the FPDM will turn off the fuel pump.

If the FPDM does not out any diagnostic signal, (0 or 100% duty cycle), the PCM sets a P1233 DTC. This DTC is set if the FPDM loses power. This can also occur if the Inertia Fuel Switch is tripped.

If the FPDM outputs a 25% duty cycle, it means that the fuel pump control duty cycle is out of range. This may occurs if the FPDM does not receive a valid control duty cycle signal from the PCM. The FPDM will default to 100% duty cycle on the fuel pump control output. The PCM sets a P1235 DTC.

If the FPDM outputs a 75% duty cycle, it means that the FPDM has detected an open or short on the fuel pump control circuit. The PCM sets a P1237 DTC.
 

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I had the exact same fault code on my 1.9JTD, but I also had low power under 2500 revs, changed my egr to fix the low power & this also cured the fault code.

Blanking the egr valve before would fix the low power but not cure the fault code.
 

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I had the exact same fault code on my 1.9JTD, but I also had low power under 2500 revs, changed my egr to fix the low power & this also cured the fault code.

Blanking the egr valve before would fix the low power but not cure the fault code.
You could be onto something there, I was considering the EGR, but as the turbo has been replaced I am wondering if the vanes have been setup correctly.

Still there's no harm in whiping off the EGR and cleaning it.
 

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Any luck solving this ?

I have a P1238 constantly on my 1.9 JTD and want to know how to fix it...

Failed Component Code: Air control negative governor deviation
Fault Symptom: Negative governor deviation above limit
Warning Lamp Status: Warning Lamp Illuminated
Fault Test State: Test not complete for this Error.
Fault Code Storage State: Error Maturing-Intermittent at time of request
Event Count: 40 count
Environmental Condition One: Engine Speed: 847.08 rpm
Environmental Condition Two: Fuel Quantity: 9.72 mm3/str
Environmental Condition Three: Accelerator Pedal: 0 %
Environmental Condition Four: Rail Pressure: 313.72 Bar
Environmental Condition Five: Turbo Pressure: 952.97 mBar
Environmental Condition Six: Engine Temperature: 34 °C
 

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Same problem here.....

....also GT 1.9 JTD.

My EGR has failed before, I cleaned it and the car ran fine with the MCSF light resetting itself after the usual time period.

As pre-warned by a few guys on here the EGR failed again.....so I decided to strip it down, clean it and blank it off at both sides. At the same time I had enough time to strip down the air intake from the filter to the turbo and found the Air Mass Flow (MAF) covered in oil, so I carefully cleaned it with carb cleaner. (During my re-map in March the technician told me it was down 5 bhp on stockpower and suggested I check the MAF)

Put it all back together and the dreaded MCSF now accompanies every start-up.

Alfadiag gives me the same code, as I wanted to clarify I had not damaged the MAF.

Car runs fine but smokes like a fire at a tyre factory! power seems slightly down and it does seem to be overfueling (low mpg).

I was'nt sure when I reset the light using alfadiag the smoke stopped.....but then returned after the next start-up when the light came back on.

So based on your comments it could be the coil on the EGR failing, hence I still get the fault after blanking it off. I'm assuming it isnt the MAF as the error code isnt MAF specific? And the overfueling is due to the ECU fail safe?:confused:
 

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You cannot just blank the egr off,as it will always give an error,the only way to do it is to have it turned off in the software.:)
 

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Without going into to much detail if you just blank them off,the ecu notices an inbalance in metered and unmetered air amounts and registers an air quantity fault,if you want it turned off we can do it via the software as part of a remap.:)
 
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