Check Engine Light Archives - Page 4 of 4 - DIY Auto Repair Auto Codes

P0171 P0172 P2187 Mercedes PCV Valve Replacement ” Running Lean”

April 8, 2018 by Reggie

Diagnose check engine light. Stored code p2187, p0171, P0174 for system running lean. Smoked intake for vacuum leaks and none found. Found engine vacuum in crankcase due to failed positive crankcase ventilation valve. Crankcase ventilation valve will need to be replaced.

PCV Valve: https://amzn.to/2IznkiY
Crank Case Breather: https://amzn.to/2IznkiY

Engine light is on with fuel trim fault codes and there is an engine knocking noise at times.
Average Reported Mileage: 69772
Tests Procedures: 1. Check for excess crankcase vacuum. Remove the dipstick and connect a vacuum gauge.

2. If vacuum is found, then the pressure regulator valve for the crankcase has failed. See related documents for a picture of the location. Read bulletin LI01.20-P-046639.

3. If no issues are found, then inspect purge valve for being stuck open per bulletin LI47.30-P-049162.

4. Also check for leaking intake per bulletin T-B-09.20/27b.

5. Read bulletin LI09.20-P-061233 and the attached photos for locations of leaks.

6. Verify all recalls and campaigns have been performed.

7. Inspect for incorrect or blocked air filters.
Tech Tips: The pressure regulator valve prevents a vacuum -50 mbar from building up in the crankcase due to the intake manifold vacuum when the gases are extracted from the crankcase. When the crankcase pressure regulator fails, engine oil can get sucked into the combustion chamber.

Ford P1450 Fuel Tank Vacuum “Most Common Cause” & How to Test

January 26, 2023April 5, 2018 by Reggie

Customer Concern: Ford P1450 Fuel Tank Vacuum “Most Common Cause” The Check Engine Light (CEL) is on, and the Powertrain Control Module (PCM) sets Diagnostic Trouble Code (DTC) P1450.

The most Concern Cause of a P1450 is the EVAP Purge Valve

An evaporative (EVAP) purge valve is a component of a vehicle’s EVAP system, which is responsible for controlling the flow of fuel vapor from the EVAP canister to the engine. The valve is typically controlled by the engine control module (ECM), which opens and closes it based on various sensor inputs, such as the engine’s vacuum level or the fuel level in the tank. When the valve is open, fuel vapor is allowed to flow from the canister to the engine, where it is burned along with the air/fuel mixture. When the valve is closed, the flow of vapor is stopped, preventing it from entering the engine. The purpose of the EVAP system is to prevent hydrocarbon emissions from escaping into the atmosphere.

Fuel Tank Emissions Vapor Canister Purge Valve Solenoid Assembly w/ Hoses & Bracket Fits 2013-2014 Ford Fusion: https://amzn.to/2EklIHh

Pocket Scan Tool: https://amzn.to/2JmtJ24

Tests/Procedures:

1. Check the canister vent solenoid and related hoses for any restrictions and repair as needed. Be sure the canister vent solenoid is open at rest as it should be.

2. If the solenoid and hoses are OK, access the charcoal canister. Verify the canister is not restricted. Replace as needed if it is, and recheck the operation.

3. The purge valve is a normally closed solenoid. Verify it is not stuck open and apply a vacuum to the fuel tank.

4. If the purge valve checks out OK and the canister appears free of any restriction, remove the fuel vent hoses as close to the fuel tank as possible. Check the hoses from the tank forward for any restrictions. If the hoses are OK and no external restrictions are found, we suspect a possible problem with the fuel tank vent valve(s) at the top of the fuel tank.

Tech Tips: Anything that causes a restriction in the venting of the Evaporative Emission (EVAP) system can cause a code P1450.

The one tool every mechanic should have: http://amzn.to/2FN2r70

One of the most common diagnostic trouble codes (DTCs) encountered on Ford vehicles is the P1450 code. This code indicates that there is a problem with the fuel tank vacuum. The P1450 code is set when the powertrain control module (PCM) detects a malfunction in the vacuum system that is used to control the EVAP system.

What Causes the P1450 Code?

There are several potential causes of the P1450 code, including a vacuum leak in the fuel tank, a malfunctioning vacuum switch, or a malfunctioning vacuum solenoid. The most common cause of this code is a vacuum leak in the fuel tank. This can occur due to a damaged or cracked fuel tank, a loose or missing gas cap, or a malfunctioning fuel tank pressure sensor.

How to Test for the P1450 Code

The first step in diagnosing the P1450 code is to check for any vacuum leaks in the fuel tank. This can be done by performing a vacuum test on the fuel tank. To perform this test, you will need a vacuum pump and a vacuum gauge.

Start by disconnecting the vacuum hose from the fuel tank pressure sensor.
Connect the vacuum pump to the disconnected hose and apply a vacuum to the fuel tank.
Use the vacuum gauge to measure the amount of vacuum in the fuel tank.
If the vacuum gauge reads less than the specified amount, there is a vacuum leak in the fuel tank.
Check for any visible leaks or damage to the fuel tank.
If the fuel tank is damaged or leaking, it will need to be replaced.
If the fuel tank is not damaged or leaking, the next step is to check the vacuum switch and solenoid.
Check the vacuum switch and solenoid for proper operation and replace them if necessary.
Clear the DTCs and test drive the vehicle to see if the P1450 code returns.

The P1450 code is a common issue faced by many car owners, but what exactly does it mean? We will explore the causes, symptoms, and solutions for the P1450 code, as well as provide tips on how to prevent it from happening in the future.

II. What is the P1450 Code? A. Definition: The P1450 code refers to a problem with the evaporative emission control system (EVAP) in a vehicle. B. Explanation of the EVAP system and its role in a vehicle’s emissions control

III. Causes of the P1450 Code A. Faulty EVAP canister purge valve B. Leaking fuel tank or fuel filler neck C. Clogged EVAP canister D. Wiring or electrical issues E. Failed vacuum switching valve F. Failed EVAP canister vent control valve

IV. Symptoms of the P1450 Code A. Check Engine Light illumination B. Failed emissions test C. Reduced fuel efficiency D. Difficulty starting the engine E. Sulfur-like odor from the fuel system

V. Solutions for the P1450 Code A. Diagnosing the problem: Using a OBD-II scanner to diagnose the specific cause of the P1450 code. B. Repairs: Fixing the specific problem identified during diagnosis, such as replacing a faulty purge valve or cleaning a clogged EVAP canister. C. Cost: The cost of repairs can vary depending on the specific cause of the P1450 code, but it is important to address the issue as soon as possible to prevent further damage.

VI. Prevention Tips A. Regularly scheduled maintenance: Having regular check-ups on your vehicle can help identify potential issues before they turn into bigger problems. B. Proper fueling: Using the correct type of fuel and avoiding overfilling the fuel tank can help prevent leaks and other issues related to the EVAP system. C. Avoiding extreme temperatures: Extreme hot or cold temperatures can damage EVAP system components, so it is best to avoid leaving your car in extreme conditions.

VII. Conclusion A. Recap of key points B. Emphasizing the importance of addressing the P1450 code as soon as possible C. Encourage readers to share their own experiences with the P1450 code and any tips they have for addressing it.

Code P0410 P0411 P0412 Secondary Air Injection “Test this First”

April 4, 2018 by Reggie

A common issue with GM, VW and Audi vehicles are air injection flow codes like p0410, p0411, and p0412.
If you check engine light is on with any of these engine codes then in this video I will show you one of the most common faults when it comes to air injection codes and how to check if your air pump is working. I have personally seen my fair share.

Pocket Scan Tool: https://amzn.to/2GDzc2z
VW Air Injection Pump: https://amzn.to/2uRuaym

The one tool every mechanic should have: http://amzn.to/2FN2r70

BMW P0014 P0015 Intake Exhaust valve timing “Try This First”

April 4, 2018 by Reggie

2007 BMW X3 3.0SI 3.0L, L6
Customer Concern: Check engine light is on.
Tests/Procedures: 1. Check for sludging of oil and lack of oil changes during the vehicle history.

VVT Solenoid: https://amzn.to/2IczM7N
Pocket Code Reader: https://amzn.to/2DZpdCM
Power Probe tester: http://amzn.to/2FN2r70

Sludging of the oil and burnt oil can lead to the camshafts not being able to adjust as commanded by the engine control module. Oil pressure is controlled by solenoids mounted on the engine near the camshafts. Poor flow and lack of oil pressure will cause slow or no movement of the camshaft timing mechanism.

2. Check the solenoids themselves for power at one of the wires to the solenoid. Ground the other wire at the solenoid and the solenoid should click. If not, the solenoid is faulty. Different codes should be set for faulty solenoids, but it should be verified anyway.

3. Remove the solenoids and look at the oil or lack of oil, that comes out of the solenoids when removed. If gummed up and burnt, oil supply could be an issue.

4. Incorrect timing of the engine can also lead to this code being set. If the engine was recently disassembled and the proper tools were not used for camshaft timing, the engine will need to be set up properly.
Tech Tips: Both fault codes relate to incorrect camshaft timing or camshaft timing control problems.

P0420 HONDA Catalyst System Efficiency (Bad Cat??)

March 9, 2018February 16, 2018 by Reggie

Repair Information for P0420 Honda code. Learn what does P0420 Honda Catalyst System Efficiency Below Threshold Bank 1 means and how to diagnose p0420 code

Diagnosing a P0420

Tests/Procedures: 1. Verify that the fuel trims on both banks are good at idle and when driving the vehicle. It is possible to have the fuel trim at 20% and not set a fuel trim code and cause the catalytic converter to not function properly.

2. If the fuel trim is only off on one bank, look for a faulty Air/Fuel (A/F) Ratio sensor, a vacuum leak or a fuel delivery problem on the bank the fuel trim is off on.

3. If the fuel trim is good and within 10% plus or minus, drive the vehicle at a steady throttle, steady cruise and monitor the rear O2 sensor operation. If the rear O2 sensor is switching rich to lean, the catalytic converter is not storing oxygen correctly. When the catalytic converter functions correctly, the rear O2 sensor should not switch. If the rear O2 sensor switches at a steady cruise while driving, the catalytic converters are failing.

4. Since this vehicle uses Air/Fuel (A/F) Ratio sensors instead of front O2 sensors, if the vehicle has high mileage, it is always wise to replace the front A/F Ratio sensors if the catalytic converters are faulty and need to be replaced. In some cases, the A/F Ratio sensors can cause a false code P0420.

On the vehicle in the video, The only reason the cat was replaced on this car was due to rust and it set the p0420 the day after. And here is the follow-up video to the first on. A complete guide to diagnosing a p0420 on a Honda CRV

Below are some very useful comments left on my subreddit post. That could definitely be useful in diagnosing a p0420 code.

Why Does a Catalytic Converter Fail?

P0420 Failed Catalytic Converters — Failed Catalytic Converters

When a CAT fails an important part of the repair is determining why it failed in the first place and correcting the problem so the new one does not have a repeat failure. CATS have no moving parts and no consumable components, so they should last the life of the vehicle; if a CAT fails there is always some kind of external cause involved.

This can be physical damage from an impact or vibration, poisoning with a foreign substance such as fuel system cleaners or oil additives, or from an engine burning oil or coolant. A very common cause of CAT failure is fuel contamination from a misfire condition or an engine that is constantly running rich; any unburned fuel exiting the engine hits the CAT and burns there, which raises temperatures inside the CAT high enough to melt and damage the internal ceramic honeycomb causing it to crumble apart. This is usually visible if you look inside the old cat when it is removed.

Did a Misfire Cause my Catietic Converter to fail?

That is probably what is happening in the car in the video. If you watch the front O2 it is at a pretty constant 600+ mv, which is a rich condition; a normal front O2 should be switching frequently above and below 450mv, more like the rear O2 is doing. The sensor is alive and operational, when he snaps the throttle open you can see the voltage spike low momentarily from all the extra air entering the engine when the throttle is opened. That engine is dumping unburned fuel down the exhaust, and that is the likely cause of both of the converter failures although the mechanic in the video does not mention nor check it. Odds are if he installs a third one it too will be back with a P0420 failure in a few weeks.

That engine probably has high fuel pressure, a dripping injector, a vacuum leak (which drops MAP so the ECM thinks the engine is under load), a faulty thermostat causing the engine to run too cold, or an out of calibration intake air temp or coolant temp sensor causing the rich fuel mixture, or engine misfire that is killing the CATs.

Using Fuel Trim Data to Diagnose a P0420 code (Rich or Lean Condition)

Response:

So, this is your original content? I did not realize you created the video; That’s awesome!

I was looking at your scan PIDs in the video and noticed that one was front O2 and it was hanging at 600mv; that must be a calculated value in the scan tool itself then. It might be interesting to look at the fuel trims to see if the PCM is commanding a lean correction in response to a rich mixture. If your trims are centered then there probably is not a mixture problem, but if fuel trims are maxed out lean I think I would investigate a little to find out why.

Air/fuel sensors are sent a bias voltage from the PCM; I believe the exact voltage is different for different manufacturers. The output voltage from the sensor varies above and below that median (lambda). Lambda goes negative when the mixture is rich, and positive when the mixture is lean. It is supposedly a much more precise measurement of fuel mixture than a traditional O2 sensor can provide.

I read somewhere that you can convert lambda value (if it shows on your scan tool) to actual air/fuel ratio measurement by multiplying lambda by 14.1

Response:

Thanks for the info. Ya, the video was a little vague. Where the customer didn’t have any problems with CEL before we put the new cat in. The old exhaust was rotted out. That was the original reason for replacement. SO I didn’t spend a whole lot of time on diagnostic. I justed cleared the light and had the customer drive it for a few days. If the CEL comes back on, I will do a new, much more in-depth video. Been close to a week now though. Oddly enuff I have had new catalytic converters set p0420 code within a day of installation then code never come back again. I’ve never heard off breaking in a new cat. but in these very few causes it certainly seemed that way. I’m anxiously waiting to see if this car returns. I’ll be sure to update you. It was an aftermarket cat, which I’m not too fond of.

Yeah, aftermarket CATS scare me also. I have learned the hard way to never use aftermarket CATS on a Subaru, for example. The expensive OE cats on Subarus seem to have barely enough catalyst material for them to pass the cat monitor, so what do you think a cheaper aftermarket one will do? The last time I tried an aftermarket CAT on a Subaru it was from a US manufacturer called Eastern Catalytic, which was supposed to be a top quality brand according to my sales rep. I spent hours on the phone with their tech support and even had several long phone conversations with one of their engineers when the second CAT they sent was setting P0420 faults. They never did figure out what the problem was, but after I installed an OE Subaru one the fault was gone and never returned. Of course, I never got paid for any of those hours I had to spend chasing the problem after I installed their product. If sell an aftermarket cat because the customer insists on one, I have them sign a disclaimer on the RO that states converter related fault codes will NOT be covered under our repair warranty if the MIL should come on afterward.

P0420 codes and Exhaust Leaks

By the way, you didn’t say where it was rusted, but if the original CAT you replaced was rusted through and leaking, should there not have been a Catalyst fault stored because of the air entering the exhaust stream before the repair? If not the customer may have cleared the fault code before you got the car; the first thing many people do if their MIL pops on is stop in at Autozone and have their memory wiped. Maybe this is a pre-existing condition they never bothered to tell you about. Of course, that never happens, right?

Response:

The most Concern Cause of a P1450 is the EVAP Purge Valve

What Causes the P1450 Code?

How to Test for the P1450 Code

Diagnosing a P0420

Why Does a Catalytic Converter Fail?

Did a Misfire Cause my Catietic Converter to fail?

O2 sensor and Air Fuel sensors Look the same but work Differently.

Using Fuel Trim Data to Diagnose a P0420 code (Rich or Lean Condition)

Leaking Exhaust or Bad Catietic Converter?

After Market Catiletic Converters VS OEM

P0420 codes and Exhaust Leaks