2007 IC CE200
vt365 115k miles
I was experiencing a loss of power and the computer threw codes "343 Excessive Exhaust Back Pressure" as well as "327 Power Reduced to match Cooling Sys Performance".
I have replaced the MAP sensor, cleaned up the EGR valve, ran a steel cable through the EBP sensor tube, and installed a new Garrett turbo.
This eliminated the "343 Excessive EBP" code, but there is still a general loss of power and grey smoke. I noticed that there is a considerable difference between my coolant temp and my oil temp. I understand that this will kick off the "327 Power Reduced to match Cooling Sys Performance".
Looking at DTC 327, I seem to have read that it can be several things:
-Plugged Oil Cooler
-Plugged Radiater
-Plugged CAC
-Fan Drive
-Coolant Level
I have ServiceMaxx and have been working around the lack of certain tools/gauges. I am hoping to access shore power this weekend to put the batteries on a charger while I run through all of the KOEO tests (I've read that low batteries dealing with glow plug and hydraulic brake pumps can cause issues with KOEO tests) and be able to keep a charge on my laptop and phone for the literature as I work. I have found a part number for a fuel psi gauge "TU-32-20" that seems as though it will work on the clean side test port. I am also guessing that I can get around the breakout harnesses with a Back Probe kit from NAPA.
I am throwing a few clues out there to see if experience/wisdom/superior intellect can tell me what I am or what I may do wrong.
-EBP Desired always seems to stay at 0psi
-VGT Duty Cycle seems to stay at 353.23% excepting momentary bounces to 30%-80%
-VGT Offset has been -500% (give or take)
-Injection Control Pressure is above 650psi while warming up. (I should check while cranking maybe?)
-on ServiceMaxx, the voltage Ref for the sensors and actuators is blank and to hover the mouse over them, I get the tooltip "querying ECM"
-Manifold Temp got as high as 165-170f if I remember my wife properly
-Boost pressure was no more than half of the EBP while I was test driving last. 12-15psi boost pressure I believe
I am sitting in front of a grocery store charging my electronics to make this post, and I am sure that folks don't like helping an amateur for the headaches we carry, but I thank you for your attention and experience.
My intentions are to follow through with the complete Performance diagnostic procedures as soon as I can get the gauges. I also had plans to check on the wiring for the ECM/IDM. Someone mentioned cleaning up the relay terminals. I will take a look at the ICPR when I have the ECM out of the way. It doesn't seem difficult to inspect/clean, and can't hurt. Does the Vref numbers missing indicate a symptom of anything? If the ECM couldn't detect those voltages, there would certainly be codes yeah?
So, the coolant/oil temp difference, and the "327 Power Reduced to match Coolant System Performance" is a visible code that I can see, but I would hate to "solve" another symptom and not address the root cause.
This is a horrible presentation, I know, but I will update as I move along and maybe someone down the road will appreciate the puzzle.
vt365 115k miles
I was experiencing a loss of power and the computer threw codes "343 Excessive Exhaust Back Pressure" as well as "327 Power Reduced to match Cooling Sys Performance".
I have replaced the MAP sensor, cleaned up the EGR valve, ran a steel cable through the EBP sensor tube, and installed a new Garrett turbo.
This eliminated the "343 Excessive EBP" code, but there is still a general loss of power and grey smoke. I noticed that there is a considerable difference between my coolant temp and my oil temp. I understand that this will kick off the "327 Power Reduced to match Cooling Sys Performance".
Looking at DTC 327, I seem to have read that it can be several things:
-Plugged Oil Cooler
-Plugged Radiater
-Plugged CAC
-Fan Drive
-Coolant Level
I have ServiceMaxx and have been working around the lack of certain tools/gauges. I am hoping to access shore power this weekend to put the batteries on a charger while I run through all of the KOEO tests (I've read that low batteries dealing with glow plug and hydraulic brake pumps can cause issues with KOEO tests) and be able to keep a charge on my laptop and phone for the literature as I work. I have found a part number for a fuel psi gauge "TU-32-20" that seems as though it will work on the clean side test port. I am also guessing that I can get around the breakout harnesses with a Back Probe kit from NAPA.
I am throwing a few clues out there to see if experience/wisdom/superior intellect can tell me what I am or what I may do wrong.
-EBP Desired always seems to stay at 0psi
-VGT Duty Cycle seems to stay at 353.23% excepting momentary bounces to 30%-80%
-VGT Offset has been -500% (give or take)
-Injection Control Pressure is above 650psi while warming up. (I should check while cranking maybe?)
-on ServiceMaxx, the voltage Ref for the sensors and actuators is blank and to hover the mouse over them, I get the tooltip "querying ECM"
-Manifold Temp got as high as 165-170f if I remember my wife properly
-Boost pressure was no more than half of the EBP while I was test driving last. 12-15psi boost pressure I believe
I am sitting in front of a grocery store charging my electronics to make this post, and I am sure that folks don't like helping an amateur for the headaches we carry, but I thank you for your attention and experience.
My intentions are to follow through with the complete Performance diagnostic procedures as soon as I can get the gauges. I also had plans to check on the wiring for the ECM/IDM. Someone mentioned cleaning up the relay terminals. I will take a look at the ICPR when I have the ECM out of the way. It doesn't seem difficult to inspect/clean, and can't hurt. Does the Vref numbers missing indicate a symptom of anything? If the ECM couldn't detect those voltages, there would certainly be codes yeah?
So, the coolant/oil temp difference, and the "327 Power Reduced to match Coolant System Performance" is a visible code that I can see, but I would hate to "solve" another symptom and not address the root cause.
This is a horrible presentation, I know, but I will update as I move along and maybe someone down the road will appreciate the puzzle.
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