Lately I've been dealing with the P1440 code on my 1999 Nissan Maxima. The car is meticulously maintained and has 82,5xx miles on it as of this morning.

This problem cropped up a few months ago, but I've been lazy about it. Time to get it fixed.

The funny thing is, the CEL will stay on for weeks on end, and then go off for a day or two or even half a day. Then it will come back on. This leads me to believe it's not a leak per se, but a bad piece of hardware (such as some sensor). I think this also means that the gas cap theory doesn't apply here. If the cap was bad, it's bad. It wouldn't only be bad sometimes. Correct?

Now, what I have replaced recently while trying to fix other issues is:

Absolute Pressure Sensor
MAP/BARO Sensor

Everything else is fair game. What is the likely cause? I've searched and people have replaced canisters, gas caps, etc. I'm wondering if my canister (the one under the rear left quarter panel) is bad. I inspected it and it looked to be in good shape, so I'm not sure.

Any ideas? Please chime in if you've had a similar issue.

 

Also, don't know if it's related (and it doesn't really bother me).

But if I'm sitting a light, I can feel the car stall for literally half a second and then it keeps idling like it was (at normal 500-800 RPM - depending on which gear I'm in). It's literally like a small blip in the idle that lasts the blink of an eye.

 

Since you're a 99, I'm gonna say it's a coil issue. I've had this symptom with my 99 and it turned out to be a coil. It seems like the car hiccups. Other than coils, check your plugs if you havent done so already.

 

Nah my coils are fine and my plugs too. The car is meticulously maintained. I swapped coils recently to 96 ones like 3 months ago. They have been functioning properly.

Could be an injector though I guess? Oh well, that's not a big issue.

The P1440 is an issue.

 

too lazy to look through the FSM but did you check out how to diagnosis the EVAP system? go through that and if it doesn't check out, i would just replace it. i don't think it should be too expensive.

for that little hesitation, when was the last time you cleaned your IACV?

 

i think this might be the problem.. lift the rear driver side of the car so the wheels are hanging low giving access to behind the wheel (wheel well wall). There is a small plastic triangular shaped cover. it has two plastic tabs holding it in. remove that. then follow harness coming from the purge canister back toward the front. The part that was covered near the wheel well has a habit of corroding (the rubber on the wire becomes brittle and breaks, NY winter salts/age to blame) fix that break. and you'll be set since you've changed everything else.

I soldered it and shrink wrapped.. I expect nothing less from you Ilyak.

I like you bought all new Evap stuff and then found this prob in the end.. good thing i have 2 a32s so... i can re use the parts... when my96's evap starts to malf.

 

Damn I've been so busy I forgot I had made this thread.

I took a gander at the FSM and saw a bunch of tests using the Nissan Tool (which I don't have).

I'll have to take a better look at it. The canister, etc. looked good as well last time I had the car up there. I'll have to check again.

Also, I don't know if I mentioned this or if this is related but...I got the car in November of 2006. Probably since sometime in 2007, I sometimes hear a hissing sound from the rear wheel (right) wheel well. It's NOT my exhaust. But the hissing isn't constant. I'd say it happens 75% of the time. Usually, if it happens, it starts like 5 seconds of starting the car.

Is that a 99 thing? My 97 didn't do that. And I only got this code within the last 6 months.

 

dont go by looks. the canister can get clogged on the inside, no need for the tool to check what i said. just check if the wire is brittle and or broken. The FSM has procedure for checking without Nissan Tool. I.e. blowing into the hoses while pinching other hose etc.

the hissing.. possibly your fuel pump? the evap needs vaccume PSI to release anything so if at idle i dont think thats it. maybe a bad speaker gound to the rear speaker?

 

I'll check the connection you mentioned in the PM.

As far as the hissing, it's on the outside of the car. It almost sounds like a massive leak in my tire (I don't have that lol).

 

The reason it's got so many places to test is because you could have a vaccum leak anywhere in the EVAP system that would make this code crop up. That's what my 1440 code turned out to be - the hose going to the top of the EVAP canister was cracked. Start wiggling vaccum hoses at their ends in your engine bay and see if you can find a cracked hose, I bet you'll find one.

 

When I get the evap small leak code I just make a VERY thorough visual inspection like others have mentioned, and if I don't find anything I bring it to a fellow shop owner I know well who has a smoke machine.

 

Check the fuel filler tube also. I got a hole in mine from one of the supports being broken off. Water and salt did the rest.

 

I have just done all the o2 sensors on my 99 ( i have 3 )... now i hope all the codes are gone and i can pass inspection about 30 miles in the p1440 code comes up.... i also hear the hissing sound while cars running but only when the car is in the 'on' position with the key or running... no hiss sound when its off. i want to know whats the best way to go about finding the problem ... thanks for your help

 

Make sure all EVAP lines are nice and snug and not broken. Trace all the lines and blow through them wit a straw to make sure air can pass through. Blow into the intake manifold EVAP openings.

If u dont find anythin take it to a shop for a smoke test.

 

yeah im new to this evap ****... im looking at diagrams to try and do what you suggested. now i have p0153 code which is bank 2 sensor 1... i have a federal emissions car and i have already done the other 2.... does the 3rd o2 have anything to do with the evap? before i waste more money and buy the 3rd and last o2 sensor

 

Also, look at each of the little connectors on the bracket in front of the canister. I had one of the nipples broken, but the little hose held it in place so the break wasn't very visible. JY is a great source of parts.

 

thanks for the help guys.... i have done 2 of the 3 o2 sensors.... then another code came up for the 3rd o2 sensor and i was j.w. could the evap code be because of the 3rd o2 sensor needing a replacement

 

Nope - EVAP and O2 sensors are two completely separate systems. Bank 2 sensor 1 is the O2 sensor in the exhaust manifold at the front of the engine compartment.

 

did op ever figure out the issue?

I have a similar thing happening to my 99 SE now

 

This post is four years old. I'm helping maxima297 right now with a similar problem. An air leak.

 

is there another thread that you're on for this?

thanks

 

Maxima297 posted: EGR hose severed.

That thread I'd mis-named. The subject is about the same part of the car you need help with.

 

Mine is 446 and 400, evap charcoal canister crap. I'm not quite finished with it yet. So far I've replaced all but one hose, the vacuum cut valve and the charcoal canister as well as all of the clamps. I'm going to change the evap canister as soon as this rainy weather stops.

 

This quote is six years old. My '98 i30 has had this same "small blip in the idle" since I cleaned the TB/IACV/EGR guide tube two weeks ago. Car is driven every day.

It threw a P1440 once since then, two days ago and after a long freeway run which doesn't happen regularly. I re-tightened the OEM gas cap and cleared the code - time will tell if it repeats. I haven't looked at the balance of the EVAP system yet.

I would love to know how to isolate the blip in the idle against some other ECU-logged datapoint (like "triggered EVAP canister solenoid", for example") so as to have a better understanding of what the car is trying/failing to do when the idle dips. Does the CONSULT tool do this?