Persistent P050d

[Chukbacca]

Persistent P050D but engine runs perfectly – smog fail (Pentastar 3.6)

Trying to solve a P050D that is causing a California smog failure.
No CEL, engine runs great, readiness complete, but smog machine still sees the stored code.

Symptoms
Issue existed ~1 year before teardown
No drivability issues
Slightly longer crank occasionally (maybe one extra revolution)
Cold idle behaves normally
RPM ~1300 → drops smoothly to ~800

Live data during cold start:
STFT: ~0–7%
Purge command: 0%
No misfires observed

KOEO cold readings:
Coolant ~59°F
IAT ~55°F
MAP ~29.5 inHg
Fuel pressure ~40 psi
Everything looks normal.

Major Engine Work Done
Engine was opened up and several issues were found/fixed:
Lifters replaced
Rockers replaced
Passenger intake camshaft replaced (bad #3 lobe)
Timing verified at TDC afterward
Injectors replaced
Lower intake replaced
Throttle body cleaned

Several real leaks were discovered and repaired:
PCV hose replaced
PCV gasket replaced (confirmed leak via smoke test)
Purge valve replaced (was leaking vacuum at idle)
Vacuum pump replaced (weep-hole leak)
Post-repair smoke test shows no vacuum leaks.

Current Status

No check engine light
EVAP monitor complete
All readiness monitors complete
Engine runs perfectly
Only problem is stored P050D

My Current Theory

Original P050D likely came from a combination of issues that have since been fixed:
Worn intake cam lobe
Purge valve vacuum leak
PCV/vacuum leaks

Question

Has anyone seen P050D persist like this even after the root cause is fixed, especially on a Pentastar?

Trying to determine whether I’m chasing a ghost issue or if there’s something I’m missing before going down the California referee route

Thanks so much!

 

[SitKneelBend]

Persistent P050D but engine runs perfectly – smog fail (Pentastar 3.6)

Trying to solve a P050D that is causing a California smog failure.
No CEL, engine runs great, readiness complete, but smog machine still sees the stored code.

Symptoms
Issue existed ~1 year before teardown
No drivability issues
Slightly longer crank occasionally (maybe one extra revolution)
Cold idle behaves normally
RPM ~1300 → drops smoothly to ~800

Live data during cold start:
STFT: ~0–7%
Purge command: 0%
No misfires observed

KOEO cold readings:
Coolant ~59°F
IAT ~55°F
MAP ~29.5 inHg
Fuel pressure ~40 psi
Everything looks normal.

Major Engine Work Done
Engine was opened up and several issues were found/fixed:
Lifters replaced
Rockers replaced
Passenger intake camshaft replaced (bad #3 lobe)
Timing verified at TDC afterward
Injectors replaced
Lower intake replaced
Throttle body cleaned

Several real leaks were discovered and repaired:
PCV hose replaced
PCV gasket replaced (confirmed leak via smoke test)
Purge valve replaced (was leaking vacuum at idle)
Vacuum pump replaced (weep-hole leak)
Post-repair smoke test shows no vacuum leaks.

Current Status

No check engine light
EVAP monitor complete
All readiness monitors complete
Engine runs perfectly
Only problem is stored P050D

My Current Theory

Original P050D likely came from a combination of issues that have since been fixed:
Worn intake cam lobe
Purge valve vacuum leak
PCV/vacuum leaks

Question

Has anyone seen P050D persist like this even after the root cause is fixed, especially on a Pentastar?

Trying to determine whether I’m chasing a ghost issue or if there’s something I’m missing before going down the California referee route

Thanks so much!

Did you clear the code after the fix? They might be reading "stored" instead of "active" codes

 

[Sherman Bird]

Persistent P050D but engine runs perfectly – smog fail (Pentastar 3.6)

Trying to solve a P050D that is causing a California smog failure.
No CEL, engine runs great, readiness complete, but smog machine still sees the stored code.

Symptoms
Issue existed ~1 year before teardown
No drivability issues
Slightly longer crank occasionally (maybe one extra revolution)
Cold idle behaves normally
RPM ~1300 → drops smoothly to ~800

Live data during cold start:
STFT: ~0–7%
Purge command: 0%
No misfires observed

KOEO cold readings:
Coolant ~59°F
IAT ~55°F
MAP ~29.5 inHg
Fuel pressure ~40 psi
Everything looks normal.

Major Engine Work Done
Engine was opened up and several issues were found/fixed:
Lifters replaced
Rockers replaced
Passenger intake camshaft replaced (bad #3 lobe)
Timing verified at TDC afterward
Injectors replaced
Lower intake replaced
Throttle body cleaned

Several real leaks were discovered and repaired:
PCV hose replaced
PCV gasket replaced (confirmed leak via smoke test)
Purge valve replaced (was leaking vacuum at idle)
Vacuum pump replaced (weep-hole leak)
Post-repair smoke test shows no vacuum leaks.

Current Status

No check engine light
EVAP monitor complete
All readiness monitors complete
Engine runs perfectly
Only problem is stored P050D

My Current Theory

Original P050D likely came from a combination of issues that have since been fixed:
Worn intake cam lobe
Purge valve vacuum leak
PCV/vacuum leaks

Question

Has anyone seen P050D persist like this even after the root cause is fixed, especially on a Pentastar?

Trying to determine whether I’m chasing a ghost issue or if there’s something I’m missing before going down the California referee route

Thanks so much!

Look up the strategy for that code. I think the thing is fixed, and the computer hasn't cleared from Mode 6 function yet.

 

[Chukbacca]

I’ve driven it roughly 1500 miles in the last month and cleared and relearned it a few times…currently it’s got around 45 starts (roughly 1/2 of that is cold starts) and 450 miles or so … I struggle to believe it’s still gathering data…hope it’s done before my smog deadline

 

[Sherman Bird]

I’ve driven it roughly 1500 miles in the last month and cleared and relearned it a few times…currently it’s got around 45 starts (roughly 1/2 of that is cold starts) and 450 miles or so … I struggle to believe it’s still gathering data…hope it’s done before my smog deadline

Well! Gee Golly Whiz! Are you diligent in keeping the fuel tank level at or near 1/2 ? This is necessary to ensure the damned thing EVEN runs monitors!
Next, Chryslers have long been known to suspend ALL monitor functions when the temperature drops under about 41F or goes above about 95. I'm not sure about specific temps, but can tell you, as a professional, I lost hair and got gray fighting this problem on several Chrysler products until I found this in service information.

Moreover, Chrysler has been unique in their strategy of EVAP monitor clearing; so I'd recommend you find the specific Drive Cycle requirements FOR that DTC/ Evap clearance.

BUT! You stated that the drive cycle DID clear the DTC in "Current" format. Some GM vehicles keep the damned DTC in an archive of sorts for long times. Here in Texas, the powers that be really don't give a hoot if a DTC lurks in "once upon a time".

As a final note, maybe you are shooting yourself in the foot with repeated clearing, because you start the entire process all over again.

 

[Chukbacca]

In case someone has this issue in the future…100 starts and 3000 miles later, the permanent code won’t clear. Apparently if you have 20 cold starts (40 degree shift in temp) and 200 miles the smog computer ignores “permanent” codes. (Active one do require you to address the issue)
I found this out by calling the state referee. When I went back to the original smog tech, he refused to recheck due to the existing permanent code.
I went to another place and there was no issue … and the code is still there

 

[Sherman Bird]

In case someone has this issue in the future…100 starts and 3000 miles later, the permanent code won’t clear. Apparently if you have 20 cold starts (40 degree shift in temp) and 200 miles the smog computer ignores “permanent” codes. (Active one do require you to address the issue)
I found this out by calling the state referee. When I went back to the original smog tech, he refused to recheck due to the existing permanent code.
I went to another place and there was no issue … and the code is still there

So, you had a mud-headed buffoon the first time, eh?

 

[stenerson]

I'm glad my state did away with smog testing this year.

 

[Chukbacca]

So, you had a mud-headed buffoon the first time, eh?

Well…he was right the first time as I didn’t have enough starts …he was so belligerent the 2nd time, calling the guy from the BAR stupid…I don’t plan on returning

 

[Daw14]

Your strategy works well for lots of different situations dealing with trying to recieve good service.

On any phone call, if the person does not know or tells you the wrong answer or complete bs, call back , new person answers , complete different answer .

This works about 80% of the time.

The world has been overrun with people lacking sense or knowledge.

 

[Sherman Bird]

Your strategy works well for lots of different situations dealing with trying to recieve good service.

On any phone call, if the person does not know or tells you the wrong answer or complete bs, call back , new person answers , complete different answer .

This works about 80% of the time.

The world has been overrun with people lacking sense or knowledge.

Lack of training coupled with BS training and that "I can fix anything automotive because I went to school" arrogance has long been the root of terrible results.
Today's techs are tethered to a computer notebook, and have no concept about the abstract variables germane TO systems.
Got a P0420? Today's computer nerd sells a catalytic converter, when, in more than half of the cases, the REAL underlying issue gets by them, simply because they don't ask "WHY". Combine that with flat rate, and there you have it... Car gets new cat, problem has been band-aided and the light stays off for a few moths to a year or so, and BAM! P0420 comes right back!
Customer figures the car is a POS, and trades it in, when, all that time, something as simple as a bad thermostat caused the problem. I see this pattern all the time. Meanwhile, the clueless tech thinks he's Buck Rogers!

 

[EdGs]

In case someone has this issue in the future…100 starts and 3000 miles later, the permanent code won’t clear. Apparently if you have 20 cold starts (40 degree shift in temp) and 200 miles the smog computer ignores “permanent” codes. (Active one do require you to address the issue)
I found this out by calling the state referee. When I went back to the original smog tech, he refused to recheck due to the existing permanent code.
I went to another place and there was no issue … and the code is still there

Well…he was right the first time as I didn’t have enough starts …he was so belligerent the 2nd time, calling the guy from the BAR stupid…I don’t plan on returning

I'd be calling that state referee back, and letting them know what the a-hole smog guy thinks of him....lol