CEL code P0440
#1
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I started getting a cel code PO440 "emissions system malfunction " after I started theAuto RX final rinse phase. I have cleared it several times and within a few days its back. I replaced the pcv valve, gas cap and cleaned the maf sensor ,but no help. I even changed the oil halfway thru the 3000mi rinse phase (Ihave 1000 miles to go). Any ideas what else may be the culprit, or is this to be expected till after the rinse phase is complete? The car is running great by the way, Mileage hasnt gone down etc,
Thanks, Larry
Thanks, Larry
#3
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I've never heard personally of such an issue with Auto-RX.
However, the one thing that I can think of offhand is the crankcase ventilation system. We have the PCV valve and also a hose from the front side of the engine that hooks on to a point between the air box and the throttle body (hooks on to the tube between those two things). The P0440 code is related to the EVAP system. On the throttle body there are several hoses there that hook up into the EVAP system.
That vapor that comes out of the crankcase would fly through the throttle body area. Crankcase is where the oil and the AutoRX is. However, let me make an important point. There's nothing wrong with the AutoRX. That's an excellent product and was used by my uncle on vehicles in Mexico many times (and it was a pain to import). The AutoRX will clean up whatever junk was in that crankcase and that junk that may have been deposits or stuck to the sides of the interior of the engine and is now loose and getting heated up. That stuff can vaporize and go through the throttle body and wind up in the combustion, but before it does it would go through the area where the EVAP hoses are.
I am also going to point out from Auto-RX's own FAQ, http://www.auto-rx.com/faqs-eng.shtml
However, the one thing that I can think of offhand is the crankcase ventilation system. We have the PCV valve and also a hose from the front side of the engine that hooks on to a point between the air box and the throttle body (hooks on to the tube between those two things). The P0440 code is related to the EVAP system. On the throttle body there are several hoses there that hook up into the EVAP system.
That vapor that comes out of the crankcase would fly through the throttle body area. Crankcase is where the oil and the AutoRX is. However, let me make an important point. There's nothing wrong with the AutoRX. That's an excellent product and was used by my uncle on vehicles in Mexico many times (and it was a pain to import). The AutoRX will clean up whatever junk was in that crankcase and that junk that may have been deposits or stuck to the sides of the interior of the engine and is now loose and getting heated up. That stuff can vaporize and go through the throttle body and wind up in the combustion, but before it does it would go through the area where the EVAP hoses are.
I am also going to point out from Auto-RX's own FAQ, http://www.auto-rx.com/faqs-eng.shtml
Why does my engine light come on?
On some engines, internal sensors for the engine light. oil light, and temperature gauge will act in an erratic manner during the cleaning phase. Do not be alarmed as Auto-Rx is removing sludge found on sensors but is NOT INDICATIVE OF A PROBLEM. Gauges will return to normal operating condition after the rinse phase.
On some engines, internal sensors for the engine light. oil light, and temperature gauge will act in an erratic manner during the cleaning phase. Do not be alarmed as Auto-Rx is removing sludge found on sensors but is NOT INDICATIVE OF A PROBLEM. Gauges will return to normal operating condition after the rinse phase.
#4
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Thanks for the reply. I know Auto RX is great product and wasnt trying to insinuate that it isnt. I was just wondering if anyone else experienced the same issue and what they did to rectify it. I'll continue to clear the code till the rinse phase is done.
Thanks
Larry
Thanks
Larry
#5
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It's one of those few products out there that have an extremely high regard, but doesn't mean anything is perfect either.
#6
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I took the advice of a friend at the Lexus dealer and purchased an oem toyota gas cap, This corrected my cel code, Again this proves to stick to Toyota parts. The new oem aftermarket cap I bought apparantly was either defective or substandard.
Larry
Larry
#7
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Spoke too soon , cel came back on today same code p0440. The reset lasts 3 to 4 days of driving then comes back. I checked hoses etc. Does this sound like a trip to the dealer is in order? Any other ideas out there?
Thanks for all thje tips, Larry
Thanks for all thje tips, Larry
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#8
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im going to try replacing the gas cap, hopefully it wiill conclude the evap issue. did u reset the code by unplug the battery or using obd reader? from what i read online and this forum. after checking hose (i had a loose hose underneath the intake box, one of the evap hose), replace gas cap. if its still on, could be a sensor near the gas tank, forgot the name. or could be the charcoal canister, which is pricey, iirc around $600.
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Ive been out of commission due to health issue, Still have the same cel code.
Once I'm mobil again I plan on taking it in to the dealer. I'll update after that.
Larry
Once I'm mobil again I plan on taking it in to the dealer. I'll update after that.
Larry
#15
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Sorry about the slow reply...still having health issues..The cel cleared itself,so I'm not sure what the problem was. The only 2 things I did that may have helped was replaced a dead battery, and changed the oil again. Theory being that disconnecting the battery cleared all codes, and changing the oil again after the rinse phase of engine cleaning may have cleared any remaining gunk on the internal sensors.
Larry
Larry