Crd 2.7 egr & maf

[lekie]

Thanks for the link - i will dig deeper.

My thinking is that if i am blowing black smoke is because the EGR valve is not closing properly and the EMS is setting the fuel on the basis that is fully closed. If carbon build up is the issue would not the delete mod not fix the problem?

[JeanLuke]

If the EGR is carbon-blocked open, the delete mod will not fix it.

The P0403 error means something is wrong on the electrical side of the EGR system - the solenoid is open circuit or short circuit. That is, the problem is in the wiring or the EGR solenoid itself.

Easy check...
The turbo vane control solenoid is the same. Just swap them and see if your EGR problem goes away and is replaced by boost control issues. If it throws a P0243 code, this is good - replace the solenoid. If not, start the painful process of tracing wires.

[bodgie]

Originally Posted by JeanLuke

Easy check...
The turbo vane control solenoid is the same. Just swap them and see if your EGR problem goes away and is replaced by boost control issues. If it throws a P0243 code, this is good - replace the solenoid. If not, start the painful process of tracing wires.

If this fixes the proble, the EGR delete would be the option I'd go for to "fix" the problem.

Jason

[kozillax]

Originally Posted by lekie

Hi All I have been putting up this issue for some time , now I need some help with a repair strategy. I will be getting my diesel service people to look at the problem but I want to direct them as to where look first for issues that maybe causing the problem.

The problem I am having is that I am regularly getting a P0403 EGR SOLENOID CIRCUIT error. When this happens the car goes into a reduced power mode. This mostly happens uphill under load. In addition, I have black smoke and irregular hunting at low speed/throttle when cold.

Performance otherwise o/k – starts and idles fine. Power is good and fuel is about 9- 10 L/100km on highways.

The Manual has a number of steps for a P0403 error which apart from electrical faults are performed to check the solenoid, vacuum line and EGR itself. I have had the solenoid replaced and I am assuming if the vacuum line was leaking the the EGR valve would be staying closed. If this is the case then I guess this would not be causing my observed issues.

The manual does not suggest inspection of the EGR just replacement. Now, given the situation do I just get my service people to remove, inspect and clean the EGR before anything else or should there be a different order of investigation?

Also, I have been using the WJ diag pro to check/clear codes and to monitor some of the functions. I am not sure if any of these have any diagnostic value but some explanation of values would help.
Mass Airflow – Mg/Str this value changes when driving – what is normal
MAF for EGR Setpoint - values?
EGR Duty Cycle – goes from zero to about 95 ??
Swirl Solenoid – normal values?
EGR op Phase = YES or NO ???

Have somebody wiring diagram this egr solenoid ? Same problem.

[Classic Boy]

I have dealt with a number of engine management faults on Jeep’s as well as other makes due to a issue of what can be described as electrical pin and socket fretting at the various sensor and control interface plugs. As the mileage increases spurious control faults that can be almost impossible to trace are often due this formentioned fretting. Random messages/codes can be generated that are hard to reproduce. I had a petrol Jeep that the trans would randomly go into limp mode, which after diagnosis was cured by hard wiring the output speed sensor to the loom and eliminate the plug and socket.