Limp mode post-DPF install.
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From: East Tennessee
Limp mode post-DPF install.
A similar thread is cross-posted on the Cruzetalk forum.
Long story short(ish):
A few months ago my 2015 Cruze diesel crapped the bed on the way to work. I received check traction control/stabilitrak/transmission warnings in the DIC prior to it dying (actually "stop engine now" message)
Towed to the local dealer the next day, and they told me it needed a new DPF (odd, because it was already replaced after I had the car for ~18 months). Unfortunately, the part was discontinued and unavailable in the US.
Eventually found a brand new one on ebay. Bought it and installed it myself. The car would at least start, run and idle then, but would stall and die when placed in gear. Sometimes it would idle smoothly any other times rough. Would always run rough through the ~1700-2200 rpm band. Was getting abnormal fuel pressure/voltage readings. Replaced DPF pressure sensor. Cone tip on MAP was broken, replaced MAP sensor. Then I was getting P0172 (too rich) DTC. Diagnostic steps in AllData manual led to faulty Fuel Pressure Regulator 2 and was cheaper to just replace entire fuel rail with brand new OEM Bosch Part. Replaced HO2 and MAF sensors, and car ran and drove. During test drive, got "DPF full/continue driving" message (incidentally that's the first time I had received that, since owning the car. I think the passive regen wasn't enabled). Made it home in limp mode. Soot level in DPF was ~75 gm. Did forced regeneration and got soot level down to 19 gm (regen took 50 minutes). Ever since, car will either idle smoothly, but die as soon as car is put gear, or it will surge when idling and still die when putting it into gear. Cleaned EGR valve and replaced fuel filter. No change. Had it towed BACK to local dealer. Their tech couldn't figure it out. The GM field tech actually came by and they both came to the conclusion the EGR Valve was getting stuck open. Begrudgingly, I bought a new GM genuine EGR valve with spacer plate, and it actually ran. Took it down the road, but a mile from home, I got the "DPF full, contine driving" message, followed about 1-2 minutes layer by "reduced power", then the same "stop engine now" message I got months ago. Soot level was 76 gm, this time. THAT forced regen only took about 20 minutes to get it back down to 10 gm. After that, it was back to the "idles fine mostly, but stalls when you put it in gear" spot I was before. So, in the past few months, I've replaced: MAP & MAF sensors, fuel rail, throttle body basket, DPF pressure sensor, EGR vacuum solenoid, EGR valve with new spacer plate, HO2 upstream sensor. All replacement parts were OEM either GM Genuine/AC Delco or Bosch. Anyway, fuel pressure is good/stable. Fuel trim on all four injectors is ±3. No evidence that the Fuel Pressure Regulator 1 (on the HPFP) is bad. No evidence any injector is bad.
WHAT THE HELL IS WRONG WITH MY CAR?!
Long story short(ish):
A few months ago my 2015 Cruze diesel crapped the bed on the way to work. I received check traction control/stabilitrak/transmission warnings in the DIC prior to it dying (actually "stop engine now" message)
Towed to the local dealer the next day, and they told me it needed a new DPF (odd, because it was already replaced after I had the car for ~18 months). Unfortunately, the part was discontinued and unavailable in the US.
Eventually found a brand new one on ebay. Bought it and installed it myself. The car would at least start, run and idle then, but would stall and die when placed in gear. Sometimes it would idle smoothly any other times rough. Would always run rough through the ~1700-2200 rpm band. Was getting abnormal fuel pressure/voltage readings. Replaced DPF pressure sensor. Cone tip on MAP was broken, replaced MAP sensor. Then I was getting P0172 (too rich) DTC. Diagnostic steps in AllData manual led to faulty Fuel Pressure Regulator 2 and was cheaper to just replace entire fuel rail with brand new OEM Bosch Part. Replaced HO2 and MAF sensors, and car ran and drove. During test drive, got "DPF full/continue driving" message (incidentally that's the first time I had received that, since owning the car. I think the passive regen wasn't enabled). Made it home in limp mode. Soot level in DPF was ~75 gm. Did forced regeneration and got soot level down to 19 gm (regen took 50 minutes). Ever since, car will either idle smoothly, but die as soon as car is put gear, or it will surge when idling and still die when putting it into gear. Cleaned EGR valve and replaced fuel filter. No change. Had it towed BACK to local dealer. Their tech couldn't figure it out. The GM field tech actually came by and they both came to the conclusion the EGR Valve was getting stuck open. Begrudgingly, I bought a new GM genuine EGR valve with spacer plate, and it actually ran. Took it down the road, but a mile from home, I got the "DPF full, contine driving" message, followed about 1-2 minutes layer by "reduced power", then the same "stop engine now" message I got months ago. Soot level was 76 gm, this time. THAT forced regen only took about 20 minutes to get it back down to 10 gm. After that, it was back to the "idles fine mostly, but stalls when you put it in gear" spot I was before. So, in the past few months, I've replaced: MAP & MAF sensors, fuel rail, throttle body basket, DPF pressure sensor, EGR vacuum solenoid, EGR valve with new spacer plate, HO2 upstream sensor. All replacement parts were OEM either GM Genuine/AC Delco or Bosch. Anyway, fuel pressure is good/stable. Fuel trim on all four injectors is ±3. No evidence that the Fuel Pressure Regulator 1 (on the HPFP) is bad. No evidence any injector is bad.
WHAT THE HELL IS WRONG WITH MY CAR?!
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