Code P0308
Thread Starter
|
4wd Low
Joined: Nov 2022
Posts: 12
Likes: 1
I got the Forscan usb adapter. Ran some tests, however a lot of the test results said "seems like this test is not supported". here are the results of the test that it allowed me to run.
(OK) [15:56:48.540] KOEO Injector Electrical Self Test has been started
(OK) [15:57:04.503] Test completed successfully, no errors found
OK) [16:03:04.344] Key On Engine Off On Demand Self-Test has been started
(OK) [16:03:08.054] Test completed successfully, no errors found
==DTC P0269===
Code: P0269 - Cylinder #3 Contribution/Balance
Module: Powertrain Control Module
Diagnostic Trouble Code details
Cylinder #3 Contribution/Balance
Follow the routines in the service manual to resolve the DTC listed.
===END DTC P0269===
===DTC P0284===
Code: P0284 - Cylinder #8 Contribution/Balance
Module: Powertrain Control Module
Diagnostic Trouble Code details
Cylinder #8 Contribution/Balance
Follow the routines in the service manual to resolve the DTC listed.
===END DTC P0284===
Unfortunately the possible causes for this are not minor.
any advice is appreciated.
(OK) [15:56:48.540] KOEO Injector Electrical Self Test has been started
(OK) [15:57:04.503] Test completed successfully, no errors found
OK) [16:03:04.344] Key On Engine Off On Demand Self-Test has been started
(OK) [16:03:08.054] Test completed successfully, no errors found
==DTC P0269===
Code: P0269 - Cylinder #3 Contribution/Balance
Module: Powertrain Control Module
Diagnostic Trouble Code details
Cylinder #3 Contribution/Balance
Follow the routines in the service manual to resolve the DTC listed.
===END DTC P0269===
===DTC P0284===
Code: P0284 - Cylinder #8 Contribution/Balance
Module: Powertrain Control Module
Diagnostic Trouble Code details
Cylinder #8 Contribution/Balance
Follow the routines in the service manual to resolve the DTC listed.
===END DTC P0284===
Unfortunately the possible causes for this are not minor.
any advice is appreciated.
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
Before the first start of the day, after it's set for at least 6-8 hours run the injector self test(buzz test). What should happen once you confirm to run the test is all 8 injectors buzzing at once. It will sound similar to a pissed off hornets nest(If you've never heard that sound in person I highly recommend it). Next each injector will fire one at a time in sequential order. You want to hear a crisp buzz from each and all relatively the same. This test confirms the connections between the PCM, IDM, and injectors are good, and the condition of the injector solenoids.
If all that checks out ok then it may be time for a round or two of whac a mole to see if the codes follow.
If all that checks out ok then it may be time for a round or two of whac a mole to see if the codes follow.
Butt-Head
Joined: Apr 2004
Posts: 9,412
Likes: 2,901
From: Reed Point, MT
I didn't see it mentioned, and you say it runs great, but an engine mechanical problem can cause the misfire detection to lose its mind. Lower compression due to cylinder wall, piston, piston ring, connecting rod, or valve actuation/valve seat damage can cause it too. I hope it's something easy like an injector issue for you though!
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,111
From: Rio Rico, AZ.
I didn't see it mentioned, and you say it runs great, but an engine mechanical problem can cause the misfire detection to lose its mind. Lower compression due to cylinder wall, piston, piston ring, connecting rod, or valve actuation/valve seat damage can cause it too. I hope it's something easy like an injector issue for you though!
Diesel engines RELY upon good compression, especially when cold, to provide the necessary heat on the combustion chamber to achieve ignition when the fuel is injected. A worn out engine may run well when it's fully warmed up, but the truth will be revealed when the engine is cold. Engine misfires first thing in the morning that clear up as it warms up are a clear indicator.
FTE Chapter Leader
Joined: Jan 2005
Posts: 13,086
Likes: 4,697
From: Henderson, NV
The guys have pretty much got you covered above. If you can manage it, log data all the way from when you first start the truck through all the way until it has been driven around and has warmed up. Then plug that data into the PID Charting Tool @udsuth78 mentioned. Post up the charts generated so we can take a look at what the PCM is commanding the engine to do versus what the engine is actually doing. Do you have any service history on the truck?
Thread Starter
|
4wd Low
Joined: Nov 2022
Posts: 12
Likes: 1
First I would like to say thank you to everyone that replied. Here is what i am thinking please tell me if I am wrong. The truck has 75k miles and I have reason to believe that the person I bought it from has done the maintenance. I am trying to get the truck to pass smog. The truck failed the cylinder balance test and all of the possible fixes for that are major engine repair or rebuild. I believe that the cylinder balance problem is the most likely cause of my P0308 code that cause the truck to fail smog test. If I am correct then I would have to pull the motor and rebuild it to correct the cylinder balance problem. Maybe i am wrong in coming to this conclusion, it would not be the first time that I have been wrong and certainly not the last. once again I appreciate anyone input on this.
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,111
From: Rio Rico, AZ.
First I would like to say thank you to everyone that replied. Here is what i am thinking please tell me if I am wrong. The truck has 75k miles and I have reason to believe that the person I bought it from has done the maintenance. I am trying to get the truck to pass smog. The truck failed the cylinder balance test and all of the possible fixes for that are major engine repair or rebuild. I believe that the cylinder balance problem is the most likely cause of my P0308 code that cause the truck to fail smog test. If I am correct then I would have to pull the motor and rebuild it to correct the cylinder balance problem. Maybe i am wrong in coming to this conclusion, it would not be the first time that I have been wrong and certainly not the last. once again I appreciate anyone input on this.
https://www.ebay.com/itm/39397828010...BlBMUIDvguuMYQ
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,111
From: Rio Rico, AZ.
Another point to look for would be perhaps a worn out intake cam lobe. Check to see that all the rocker arms are moving the same distance. A worn exhaust lobe with produce a backfire/popping noise back up through the intake.
Thread Starter
|
4wd Low
Joined: Nov 2022
Posts: 12
Likes: 1
Thank you for your reply, and I agree diesel engines are simple. no need for primary or secondary ignition components. Unfortunately California Emissions have complicated the once simple diesel engine. As I mentioned the truck runs great. the misfire on cylinder on #8 that causes the p0308 is not causing any detectable malfunction that can be felt when driving the truck. I realize that the problem may be in its infancy at this point. Just frustrating that it cant pass smog for this reason. Yet another good reason to leave what used to be a nice state to live in. Once again I want to thank everyone for your input on this. I think I will try to find the black CPS as a last effort.
Tuned
Joined: May 2021
Posts: 363
Likes: 121
From: Montana
Maybe I'm missing something, but cylinder 3 and cylinder 8 failing a CCT is usually something to ignore, especially if truck is running fine without a miss or stumble.
Do you have a SES light on?
Fortunately I don't know anything about passing a smog test in California, but surely they don't run a CCT?
Do you have a SES light on?
Fortunately I don't know anything about passing a smog test in California, but surely they don't run a CCT?
Thread Starter
|
4wd Low
Joined: Nov 2022
Posts: 12
Likes: 1
Yes my thread was P0308, and I do have a SES light on and it is the reason I failed smog test The truck works great and my only concern is passing smog so it can be registered to drive on the street.
Can this really be done reflash the PCM to ignore a code? and if so what do I need to buy to program/reflash the PCM?
I agree sick and tired of the EPA. If they are concerned about the air quality then a smog check would consist of tail pipe emissions and nothing more.
Can this really be done reflash the PCM to ignore a code? and if so what do I need to buy to program/reflash the PCM?
I agree sick and tired of the EPA. If they are concerned about the air quality then a smog check would consist of tail pipe emissions and nothing more.