I have a 2006 Envoy l6 4.2 4x4. It’s got 220,000 miles on it. I am the original owner. This car has been well taken care of. It’s in amazing shape considering how old and how many miles. It was running perfect then all of a sudden the check engine light came on. Codes p0496, p0300, p0017, p0455, and p0411. I’m a chick and I don’t know much about it but I know a little. I’d rather not take it to a shop because they charge an arm and a leg and I can’t afford much right now. I need advise. I love this car, it’s had regular oil changes at every 3,000 even with running full synthetic since about 150,000 miles. I take care of my car but all these codes have me worried!
NEED HELP Multiple codes
- Thread starter Sworsley
- Start date
p0411 is for the secondary air injection system. I thought by 2006 that system was gone?
p0300 is a random misfire. If you were to keep driving, it would probably give another code like p0301,p0302,p0303,p0304,p0305,p0306. I would be willing to bet you have a coil, or plug that needs replacement. Likely around cylinder #5 for the coil (most common failed coil for this engine)
p0017 looks to be for the VVT/Camshaft Actuator exhaust, and I know very little about these systems
o0455 and p0496 looks to be related to the purge solenoid or canister
I will let someone in that knows these engines better than I.
p0300 is a random misfire. If you were to keep driving, it would probably give another code like p0301,p0302,p0303,p0304,p0305,p0306. I would be willing to bet you have a coil, or plug that needs replacement. Likely around cylinder #5 for the coil (most common failed coil for this engine)
p0017 looks to be for the VVT/Camshaft Actuator exhaust, and I know very little about these systems
o0455 and p0496 looks to be related to the purge solenoid or canister
I will let someone in that knows these engines better than I.
djthumper
Administrator
Take care of the P0496 first and the others may self repair.
p0496 -
NAPA Part Numbers:
Canister Purge Solenoid (2-28245)
Canister Vent Valve (2-28249)
p0300 - Random misfire
p0017 - Crankshaft Position Sensor and the Camshaft Position Sensor are out of alignment by a certain number of degrees
p0455 - Check your fuel cap - large leak in the evaporative emission control system
p0411 - ECM has detected incorrect flow in the secondary air injection system
p0496 -
Canister Purge Solenoid (2-28245)
Canister Vent Valve (2-28249)
p0300 - Random misfire
p0017 - Crankshaft Position Sensor and the Camshaft Position Sensor are out of alignment by a certain number of degrees
p0455 - Check your fuel cap - large leak in the evaporative emission control system
p0411 - ECM has detected incorrect flow in the secondary air injection system
Mooseman
Moderator
It's the other way around. They started in 2004 and onward.
p0411 should be one of your first priorities to fix the SAIS. It can cause all sorts of issues including lean conditions and misfires.
P0496 is an EVAP purge issue. If it's allowing air flow when not commanded, it could cause a lean condition as well. Another one to fix first.
After fixing those, clear your codes and re-assess. The misfires may clear themselves.
Mooseman
Moderator
And my knowledge base expands a bit more.. Think I need a bigger hard drive or more RAM LOL
djthumper
Administrator
find a car friend and buy them some beer. Get the advice from the forum and hopefully the car friend will be able to address most without bankrupting you or destroying your vehicle.
djthumper
Administrator
Last year I think it was when I had all my plugs replaced with new ACDelco plugs. One of them was bad. When it was pulled out it had oil on it which I assumed was why it went bad. But where would the oil be coming from? I also had a shop put a new intake manifold gasket in about 6 months ago.
christo829
Member
When I had water in my SAIS pump, it was because the solenoid controlled valve up on the engine was not sealing properly. That leaves you with an exhaust leak that can affect other parts of the emission system. I eventually had the SAIS deleted with a tune, blocked off the port on the engine, and took off the pump.
Was that cap replacement before or after these codes came up? I had an aftermarket cap on my TB that would intermittently leak. Got an AC Delco one, and haven't seen that leak since.
The bad plug you found last year...was the oil burned on to the electrode, or was it wet on the threads? If it was wet on the threads, that was most likely just due to a leak from the gasket around the plug well, and not something that would have affected plug performance, unless it was swimming in it. If they repalced all those gaskets, that one may have not seated properly. Also, did they just do the plugs? If so, you may have a coil that's going bad. If you can get your hands on a scanner that will show you real time sensor data, including misfires, you can narrow down what cylinder is misfiring. Then take that coil and swap it with one of the other coils that's not misfiring. If the problem follows the coil, there's your problem. If it stays on the same cylinder it was on, put that old coil back where it originally was, and swap the plug. If it follows the plug, then that plug should be replaced. It's entirely possible to have a bad plug new out of the box.
Purge valve I'd just go ahead and replace, but you could try pulling it, testing it and cleaning it if you're so inclined.
Then clear and recheck codes.
Good Luck!
Chris
Was that cap replacement before or after these codes came up? I had an aftermarket cap on my TB that would intermittently leak. Got an AC Delco one, and haven't seen that leak since.
The bad plug you found last year...was the oil burned on to the electrode, or was it wet on the threads? If it was wet on the threads, that was most likely just due to a leak from the gasket around the plug well, and not something that would have affected plug performance, unless it was swimming in it. If they repalced all those gaskets, that one may have not seated properly. Also, did they just do the plugs? If so, you may have a coil that's going bad. If you can get your hands on a scanner that will show you real time sensor data, including misfires, you can narrow down what cylinder is misfiring. Then take that coil and swap it with one of the other coils that's not misfiring. If the problem follows the coil, there's your problem. If it stays on the same cylinder it was on, put that old coil back where it originally was, and swap the plug. If it follows the plug, then that plug should be replaced. It's entirely possible to have a bad plug new out of the box.
Purge valve I'd just go ahead and replace, but you could try pulling it, testing it and cleaning it if you're so inclined.
Then clear and recheck codes.
Good Luck!
Chris
Mooseman
Moderator
Water in it means the valve wasn't working properly and condensation happened. It can damage the blower. Test it for proper operation.
If it's oil on top of the plug (non-combustion side), that would be the valve cover gasket allowing oil into the plug well. If it's just a little bit, it's not something to worry about and wouldn't really bother anything. If it's a lot, then that would need to be looked after.
Where did you get the plugs? If it's eBay or Amazon, just be aware that there are a lot of fakes floating around.
gmtnation.com
Fix the SAIS and check those plugs.
If it's oil on top of the plug (non-combustion side), that would be the valve cover gasket allowing oil into the plug well. If it's just a little bit, it's not something to worry about and wouldn't really bother anything. If it's a lot, then that would need to be looked after.
Where did you get the plugs? If it's eBay or Amazon, just be aware that there are a lot of fakes floating around.
Counterfeit ACDelco Plugs
I wasn't looking for plugs, but saw this over at Amazon. ACDelco 41-103 Professional Iridium Spark Plug (6 Pack) $16.00 That works out to about @2.66 EACH. free shipping with...
gmtnation.com
Fix the SAIS and check those plugs.
Water in it means the valve wasn't working properly and condensation happened. It can damage the blower. Test it for proper operation.
If it's oil on top of the plug (non-combustion side), that would be the valve cover gasket allowing oil into the plug well. If it's just a little bit, it's not something to worry about and wouldn't really bother anything. If it's a lot, then that would need to be looked after.
Where did you get the plugs? If it's eBay or Amazon, just be aware that there are a lot of fakes floating around.
Counterfeit ACDelco Plugs
I wasn't looking for plugs, but saw this over at Amazon. ACDelco 41-103 Professional Iridium Spark Plug (6 Pack) $16.00 That works out to about @2.66 EACH. free shipping with...
Fix the SAIS and check those plugs.
I bought the plugs at Napa. And it was just a little oil and not burned on either.
The fuel cap was replaced before all these codes came up. I kept getting a check engine light so I had it scanned and it always said check gas cap so I’ve replaced it several times actually. The plugs that were replaced, the oil was wet on the treads. And the vehicle has never had all new coils. I will be sure to replace those as well.
JayArr
Member
Coils are expensive ($250 for a set of 6) and you probably only need to replace #4. It sits below the rim of the cowl and water from the windshield runs down and drips on #4 causing problems. If fixing the SAIS doesn't get rid of the misfire then replace #4 alone and if that doesn't solve it buy one more and replace install it in cyl #1 and if the code comes back move it to Cyl 2 etc etc until the code goes away.
Fix the SAIS first.
Question for the others reading this thread not Sworsley, do all these codes have a common ground point? My Canadian 05 doesn't have SAIS so I'm a little in the dark on this.
Fix the SAIS first.
Question for the others reading this thread not Sworsley, do all these codes have a common ground point? My Canadian 05 doesn't have SAIS so I'm a little in the dark on this.
Mooseman
Moderator
P0455 means a large Evap leak. Because the common cause of this code is the gas cap, either loose or defective, it's not the only possible cause. There are multiple points at the gas tank that could allow a leak.
P0496 means your Evap is flowing even thoiugh it is not being commanded. This is likely a stuck purge valve. This could also be the cause of the large leak at the tank if it's continuously pulling from the charcoal canister as well as the gas tank. Fix this first and see if the other code goes away.
Fix or delete your SAIS and see if your misfire codes go away.
P0017 is an issue with the variable valve timing. Initial action would be to pull out the VVT solenoid (aka: CPAS) and either clean it or replace it. I would just replace it especially if it's old or has oil in the conenctor. Clear the codes and go from there. This would not effect any of the other codes or cause much driveability issues.
Without looking at the schematics, I have no clue. I'm surprised yours doesn't have SAIS. Look for evidence that it's been deleted like dangling connectors, missing fuses and missing hose at the air cleaner box.
And fixing the SAIS includes replacing the smog pump and secondary air injection check valve, correct??
Mooseman
Moderator
JayArr
Member
Or having your PCM (power control module) reprogrammed so it doesn't check/test the SAIS anymore.
This is smog stuff, not performance stuff. The car would run fine without it, mine never had it. There is a guy on this forum called Limequat that does pcm reprogramming, he can also tune other things up a bit while he's reprogramming it. It may be better money spent and cheaper to reprogram the PCM than buying a new smog pump.
This is smog stuff, not performance stuff. The car would run fine without it, mine never had it. There is a guy on this forum called Limequat that does pcm reprogramming, he can also tune other things up a bit while he's reprogramming it. It may be better money spent and cheaper to reprogram the PCM than buying a new smog pump.
It was never installed, there was just a block off plate on the side of the head. I figured maybe Canadian cars didn't get it, maybe that was an incorrect assumption. I know that this car was built to Canadian specs because I've found a few references in the factory service manual to items that only exist on models built for Canada. Maybe I just got lucky?
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Ok and then I reset the codes and move onto replacing the canister purge solenoid and the canister vent valve right? I’m not sure what the misfire is about. I know when I had a bad plug before my car would cut out and sputter, it’s not doing that this time.
Another thing I noticed is that when I’m putting gas in the pump shuts off ALL the time like it’s full but it’s not full. I have to keep squeezing the handle over and over to get gas in. Then sometimes it’s hard to start after getting gas. Not all the time just a few times.
Mooseman
Moderator
This is another important clue. Yes, replace both valves and also check the charcoal canister if it's plugged. Problems fuelling usually points to either a bad vent valve and/or a plugged canister. Also check that your filler and vent hoses aren't kinked.
The misfire may be related to the SAIS however it also usually throws a lean code. Once these other issues are looked after we can concentrate on the misfire if it's still there.
Ok Thank you so much for all your help. This is saving me so much money by not having to take it to a shop. I will have all these things replaced and then I’ll get back to you all and let you know the outcome. I have one more question.... my car has a lot of miles on it, how long do you think it could potentially last me? I mean do I have at least another year or so before I have to just buy a new vehicle? I only drive about 30 miles a day round trip.
There is no real rhyme or reason on how long these trucks last. I know a guy that has over 500k on his trailblaer I6, there are quite a few that have well into the 200k, and I know some that couldnt even make it to the 100k mark.
I am fast approaching 200k on my Envoy, and I am quite a spirited driver.
I am fast approaching 200k on my Envoy, and I am quite a spirited driver.
Mooseman
Moderator
I agree. A lot has to do with past maintenance. Usually the tranny goes before the engine but they can fail too. Sometimes there's no apparent reason.
Ive never had my tranny serviced. I heard that when you do, that’s when it goes out. Is that true?
No, if your trans goes out after a service, its either because they screwed up the service or it was already on its way out. I have yet to hear or see any empirical evidence that a proper trans service does anything but extend the life. Its also very simple on these vehicles.
220k miles and no tranny service ? what color is the fluid ??? a power flush is bad news , few if any places even use those machines anymore, oil change shops use a vacuum pump machine and refill , but you definetly want to change your filter wich involves dropping the pan. where are you located ? maybe a member here can help or recommend a good shop