Three Codes Popped Up P0300/P0302/P0446
- Thread starter porschpow
- Start date
The car surprisingly still runs great! The idle in gear isn't the smoothest, but it doesn't sound like its missing. That is what is weird about it. I get between 32-36 mpg mixed driving (with bias on highway more then city- No overdrive).
Now I apologize, I know very little about using multimeters, but what is the best approach to test the battery?
I will look at the spark plug at number two? How would I test the cop? the wire? SOmeone here told me to switch them out?
Now I apologize, I know very little about using multimeters, but what is the best approach to test the battery?
I will look at the spark plug at number two? How would I test the cop? the wire? SOmeone here told me to switch them out?
The best approach to test the battery is to drive your car to an auto parts store and have them test your battery. You cannot test your battery properly in your yard.
I'd switch the coil of a known good cylinder with the coil from cylinder 2. If the coil originally from cylinder 2 is bad then your misfire will move with the coil.
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I'd switch the coil of a known good cylinder with the coil from cylinder 2. If the coil originally from cylinder 2 is bad then your misfire will move with the coil.
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If the car runs good, start the engine and check voltage across the battery. Verify that you have around 14.2 V. If that checks out, as John said, take it to a car parts store (they will do a load test on it, that tells you if something is wrong internally with the battery).
If that checks out, start checking your grounds. Verify that the battery cables are in good shape, no corrosion on the terminals.
It is odd to have multiple failures for different components. It usually points to electrical, either a faulty ground, faulty charging system, faulty battery, or a faulty PCM (and hopefully it isn't that).
If that checks out, start checking your grounds. Verify that the battery cables are in good shape, no corrosion on the terminals.
It is odd to have multiple failures for different components. It usually points to electrical, either a faulty ground, faulty charging system, faulty battery, or a faulty PCM (and hopefully it isn't that).
http://engine-codes.com/p0300_toyota.html
P0300 Toyota - Random Cylinder Misfire Condition
Possible causes
- Faulty spark plug (s)
- Faulty ignition coil (s)
- Clogged or faulty fuel injector (s)
- Intake air leak
- Fuel injectors harness is open or shorted
- Fuel Injectors circuit poor electrical connection
- Ignition coils harness is open or shorted
- Ignition coils circuit poor electrical connection
- Insufficient cylinders compression
- Incorrect fuel pressure
Tech notes
The P0300 code means that a cylinder(s) is misfiring or is randomly misfiring. Start by checking for intake leaks, intake gaskets are common caused of multi-cylinder misfiring. If no leak are found the next step is to replace the spark plugs. If the problem persist more tests needs to be done to diagnose problem, see "Possible Causes"
There is a factory service bulletin for the following Toyota models:
2000-2001 Toyota Camry
2000-2001 Toyota Solara
2000-2001 Toyota Solara, Camry Factory Service Bulleting OBDII Code P0300 Code
When is the code detected?
The control module monitors the crankshaft speed and has detected a misfire condition
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/loss of power
- Hard start
- Engine hesitation
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http://engine-codes.com/p0302_toyota.html
P0302 Toyota - Cylinder 2 Misfire Detected
Possible causes
- Faulty spark plug 2
- Clogged or faulty fuel injector 2
- Faulty ignition coil 2
- Fuel injector 2 harness is open or shorted
- Fuel injector 2 circuit poor electrical connection
- Ignition coil 2 harness is open or shorted
- Ignition coil 2 circuit poor electrical connection
- Insufficient cylinder 2 compression
- Incorrect fuel pressure
- Intake air leak
Tech notes
The P0302 code means that the cylinder 2 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 2. If the problem persist more tests needs to be done to diagnose problem, see "Possible Causes"
When is the code detected?
Engine Cylinder 2 is Misfiring.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/loss of power
- Hard start
- Engine hesitation
P0302 Toyota Description
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.
P0302 Toyota - Cylinder 2 Misfire Detected
Possible causes
- Faulty spark plug 2
- Clogged or faulty fuel injector 2
- Faulty ignition coil 2
- Fuel injector 2 harness is open or shorted
- Fuel injector 2 circuit poor electrical connection
- Ignition coil 2 harness is open or shorted
- Ignition coil 2 circuit poor electrical connection
- Insufficient cylinder 2 compression
- Incorrect fuel pressure
- Intake air leak
Tech notes
The P0302 code means that the cylinder 2 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 2. If the problem persist more tests needs to be done to diagnose problem, see "Possible Causes"
When is the code detected?
Engine Cylinder 2 is Misfiring.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/loss of power
- Hard start
- Engine hesitation
P0302 Toyota Description
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.
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http://engine-codes.com/p0446_toyota.html
P0446 Toyota - EVAP System Vent Control Circuit
Possible causes
- Missing Fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Vent control valve harness is open or shorted
- Vent control valve circuit poor electrical connection
- Faulty vent control valve
Tech notes
There are factory service bulletin for the following Toyota models:
Toyota RAV4
Toyota Tercel
Toyota Paseo
Toyota Camry
Toyota Avalon
Toyota Tacoma
Toyota 4Runner
Toyota T-100
Toyota Factory Service Bulletin OBDII Code P0446
2003 – 2004 Toyota Corolla
2003 – 2005 Toyota Matrix
Toyota Factory Service Bulletin OBDII Code P0446 Corolla and Matrix
If P0446 is combine with P0440 and P0441 use this bulletin:
2000-2003 Toyota Solara
2000-2003 Toyota Avalon
2000-2003 Toyota Camry
2001-2003 Toyota Sienna
Toyota Factory Service Bulletin OBDII Code P0446 Solara, Avalon, Camry, Sienna
If only P0446 is present:
2001-2003 Toyota Sienna
Toyota Sienna Factory Service Bulletin OBDII Code P0446
When is the code detected?
The P0446 codes triggered when an improper voltage signal is sent to Engine Control Module (ECM) through EVAP canister vent control valve.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Possible a noticeable fuel odor caused by the release of fuel vapors
P0446 Toyota Description
The Evaporative System (EVAP) canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid valve responds to signals from the Engine Control Module (ECM). When the ECM sends an ON signal, the coil in the solenoid valve is energized. A plunger will then move to seal the canister vent. The ability to seal the vent is necessary for the on board diagnosis of other evaporative emission control system components.
This solenoid valve is used only for diagnosis, and usually remains opened.
P0446 Toyota - EVAP System Vent Control Circuit
Possible causes
- Missing Fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Vent control valve harness is open or shorted
- Vent control valve circuit poor electrical connection
- Faulty vent control valve
Tech notes
There are factory service bulletin for the following Toyota models:
Toyota RAV4
Toyota Tercel
Toyota Paseo
Toyota Camry
Toyota Avalon
Toyota Tacoma
Toyota 4Runner
Toyota T-100
Toyota Factory Service Bulletin OBDII Code P0446
2003 – 2004 Toyota Corolla
2003 – 2005 Toyota Matrix
Toyota Factory Service Bulletin OBDII Code P0446 Corolla and Matrix
If P0446 is combine with P0440 and P0441 use this bulletin:
2000-2003 Toyota Solara
2000-2003 Toyota Avalon
2000-2003 Toyota Camry
2001-2003 Toyota Sienna
Toyota Factory Service Bulletin OBDII Code P0446 Solara, Avalon, Camry, Sienna
If only P0446 is present:
2001-2003 Toyota Sienna
Toyota Sienna Factory Service Bulletin OBDII Code P0446
When is the code detected?
The P0446 codes triggered when an improper voltage signal is sent to Engine Control Module (ECM) through EVAP canister vent control valve.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Possible a noticeable fuel odor caused by the release of fuel vapors
P0446 Toyota Description
The Evaporative System (EVAP) canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid valve responds to signals from the Engine Control Module (ECM). When the ECM sends an ON signal, the coil in the solenoid valve is energized. A plunger will then move to seal the canister vent. The ability to seal the vent is necessary for the on board diagnosis of other evaporative emission control system components.
This solenoid valve is used only for diagnosis, and usually remains opened.
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You recently had the air intake loosened to use the AMSOIL Power Foam and two of the trouble codes have a possible cause of an air intake leak so I suspect maybe there is a gap/leak somewhere there. Try removing the air intake hose and using a clean dry cloth or paper towel, wipe off the area when the air intake hose connects at both ends, with a clamp at each end. Make sure that surface is clean as a whistle. Reattach everything and make sure it's all sealed well and the clamps are snug to eliminate the possibility of an air leak. Make sure the air filter box clips are snug and in place, clamping the air box shut tightly. Everything needs to be sealed tightly so there are no air intake leaks.
Then check the fuel cap and it's condition. If it looks old and worn, you can buy a replacement at most auto parts stores for less than $10 or so.
Then check the fuel cap and it's condition. If it looks old and worn, you can buy a replacement at most auto parts stores for less than $10 or so.
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Well here's an update....
I took out all the plugs. I had to regap them all to .044". Cylinder 2 had a real small gap. I noticed a little residue (oil in cylinder 2 and 4 spark plug bores).
I took off and re-cleaned the battery terminals and clamps (had plenty of acid build up
turned the car on and what do you know, NO ENGINE LIGHT! And the car seems to run a lot smoother and be a little more peppy!
Very happy
I did NOTICE puddles of oil in the valleys on the engine under the intake pipes (manifolds). Look to me as if it is the valve cover gaskets going. How easy is it to replace?
I took out all the plugs. I had to regap them all to .044". Cylinder 2 had a real small gap. I noticed a little residue (oil in cylinder 2 and 4 spark plug bores).
I took off and re-cleaned the battery terminals and clamps (had plenty of acid build up
turned the car on and what do you know, NO ENGINE LIGHT! And the car seems to run a lot smoother and be a little more peppy!
Very happyI did NOTICE puddles of oil in the valleys on the engine under the intake pipes (manifolds). Look to me as if it is the valve cover gaskets going. How easy is it to replace?
I'm glad you were able to get the problem sorted out.
The trouble codes will still be stored in your cars onboard computer though and they will need to be cleared, or when you go to get your car inspected and I do believe your state has emissions checks as part of the state inspection, with the trouble codes stored in the computers memory the car wont pass inspection.
To clear the codes, you'll need a code scanner/reader. Most auto parts stores and even Sears hardware sells them.
The trouble codes will still be stored in your cars onboard computer though and they will need to be cleared, or when you go to get your car inspected and I do believe your state has emissions checks as part of the state inspection, with the trouble codes stored in the computers memory the car wont pass inspection.
To clear the codes, you'll need a code scanner/reader. Most auto parts stores and even Sears hardware sells them.
Valve cover gaskets are usually pretty straightforward. Glad you gapped the plugs and got the check engine light to clear.
Drive it a couple more times. The battery being unpligged may have cleared the codes. #2 misfire probably won't come back but the others may unless it was caused by the corroded terminals (and you'd be surprised how much havoc something as simple as that can wreck on a modern car).
Drive it a couple more times. The battery being unpligged may have cleared the codes. #2 misfire probably won't come back but the others may unless it was caused by the corroded terminals (and you'd be surprised how much havoc something as simple as that can wreck on a modern car).
I saw him use this toyota packing seal to put on the head before he put on the valve cover with the new gasket. But he only to two dots/dabs of this packing stuff on it. Are you suppse to do this? DO you have to use this toyota stuff or can you use RTV silicone gasket adhesive? OR ARE YOU EVEN SUPPOSE TO USE THIS STUFF AT ALL???
In addition, they don't specify how much you torque it down to (the valve cover bolts)
BTW, THANK YOU, these videos where INCREDIBLY HELPFUL!
In addition, they don't specify how much you torque it down to (the valve cover bolts)
BTW, THANK YOU, these videos where INCREDIBLY HELPFUL!
can a leak in the exuast manifold gasket cause one cylinder to misfire
I am trying to address an ongoing misfire issue on cylinder #3 (P0303) on my 99 Corolla 148,000 miles. I have already replaced all spark plugs and wires, all 4 fuel injectors, new air filter. Car only misfires on one cylinder (#3) and only in the morning when I first start the car. Once the car reaches normal operating temperature its smooth and runs fine. In the morning on a cold start I can also smell gas from exhaust pipe.(might be running too rich?) If I drive the car before it reaches normal operating temperature the car idles rough and shivers like its going to stall but has never actually stalled. It takes a good 15 to 20 min of driving for the engine to smooth out. My mechanic thinks it can be a leak in the intake manifold gasket. My question is can a leak in the intake manifold gasket cause a misfire on only cylinder#3 (P0303)? Thank you in advance for your feedback and expertise.
I am trying to address an ongoing misfire issue on cylinder #3 (P0303) on my 99 Corolla 148,000 miles. I have already replaced all spark plugs and wires, all 4 fuel injectors, new air filter. Car only misfires on one cylinder (#3) and only in the morning when I first start the car. Once the car reaches normal operating temperature its smooth and runs fine. In the morning on a cold start I can also smell gas from exhaust pipe.(might be running too rich?) If I drive the car before it reaches normal operating temperature the car idles rough and shivers like its going to stall but has never actually stalled. It takes a good 15 to 20 min of driving for the engine to smooth out. My mechanic thinks it can be a leak in the intake manifold gasket. My question is can a leak in the intake manifold gasket cause a misfire on only cylinder#3 (P0303)? Thank you in advance for your feedback and expertise.
I use Permatex Ultra Copper or Red on valve cover gaskets. I have had very poor results with regular RTV. I don't use it to seal anything, but to let dry a bit and then put the gasket in place on the valve cover and let it dry some more, so that gasket is nice and snug. This way the gasket is guaranteed not to move around from the position it's supposed to be in when you re-install the valve cover, having to do the job all over again and preventing oil leaks from occurring later on.
You don't want to use too much gasket sealer or it will squeeze out when you tighten down the bolts and get everything messy, particularly inside. Just a very fine film all around the gasket area, just enough to hold the gasket in place.
You don't want to use too much gasket sealer or it will squeeze out when you tighten down the bolts and get everything messy, particularly inside. Just a very fine film all around the gasket area, just enough to hold the gasket in place.
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Permatex gasket sealing products found in virtually any auto parts stores have done a good job for me all the way around, except for the Permatex Blue. My favorite is Permatex Ultra Copper, as it can handle any gasket job, from standard to high temperature. http://www.all-spec.com/products/81878.html?gclid=CNWzj_WOgMECFYZzMgod2DMAPg
When you want it done right, use Permatex. :thumbsup:
One word of caution for anyone doing a transmission filter change; never use gasket sealer on the transmission pan gasket, because when the transmission pan gasket bolts are tightened down, if any gasket sealer squeezes out into and inside the transmission, the gasket sealer can plug up the very tiny fluid passages inside the transmission and lead to a hugely expensive transmission rebuild. I once saw this happen when a trained, (but apparently not too smart), automotive technician used gasket sealer on a transmission pan gasket. :thumbdown:
When you want it done right, use Permatex. :thumbsup:
One word of caution for anyone doing a transmission filter change; never use gasket sealer on the transmission pan gasket, because when the transmission pan gasket bolts are tightened down, if any gasket sealer squeezes out into and inside the transmission, the gasket sealer can plug up the very tiny fluid passages inside the transmission and lead to a hugely expensive transmission rebuild. I once saw this happen when a trained, (but apparently not too smart), automotive technician used gasket sealer on a transmission pan gasket. :thumbdown:
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