Hi, I have 2001 maxima se and I've had my fair share of problems with this car. I started this thread because I cannot figure out a source of my problem I've gotten many pending codes such as p1440 p1490 p0455 p1448. I cleared these codes many times and always they can back, but now they have disappeared and I have p0302 p1440 and p505 all pending.sice these cel codes I've had this issue here are my symptoms. The car shakes in drive or reverse at stops, yes nuetral/park helps the shaking(almost completely goes away), while accelerating severe loss of power rpms seem to stick anywhere 1800-2500 rpms more gas does not help until I floor it and it will will pass 1800-2500 rpms. Any load on my engine seems to amplify the shaking greatly such as my a/c even cutting the steering wheel. I've recently replaced my spark plugs x6, coil packs x6, air filter, and got a fuel induction service to complete my tune up. The problem went away for a solid 200 miles but came right back took about 800 miles before my cel came back on. Any advice greatly apreciated I've recently cleaned my maf sensor and cleaned my throttle body with throttle body cleaner it is NASTY behind my throttle door went to remove my iac which I do beleive is my culptit but the first screw broke and so shall the second so that's for another day,HELP

 

P0302 tells us your cylinder 2 is not firing properly - in spite of your recent replacement of spark plugs and coils. The shaking you feel further supports this line of reasoning. Time to revisit - and perhaps you have more than one cylinder misbehaving.

Your other code (p1440) indicates a problem with your Evap subsystem. Check the FSM, page EC-627 (there are 23 things to check ...,. ). One thing hits me right way: Make sure you don't have water in your tank !!! - it seems to me like you do.

The infamous p0505 indicates a problem with your IACV. There is plenty of info on the subject - just search (for "New ECU, fried in seconds ..."). And make sure your ECU is not fried. Good luck, you may need it.

 

Re. the P0505, read this document first: https://drive.google.com/file/d/0B6O...1fNlF5QjQ/view.

For more horror stories, you can optionally read this thread: https://maxima.org/forums/5th-genera...d-seconds.html.

In either case, check out your ECU ASAP. In either case, and on second thought, start with the P0505 first.

 

So your saying drop my gas tank check for water? I'm aware that if the iac shorts so does the ecm I will check my connections at the sensor and the ecm. From what I beleive all this points to my iac, I'm just hoping the iac has not shorted and hopefully is just a restriction from carbon buildup in the iac passage or restriction in my coolant passage which if I'm correct operates the plunger inside the iac. Also how much is an iac because after I test my ecm i guess I'll make the decision to do my intake manifold gasket in search of vacuum leaks and at the same time clean then replace my throttle body gasket, it's apparent to me I'm going to have to drill out the screws holding my iac so hopefully I can jam some screws in there after replacing it or replace my throttle body for that reason which would suck.

 

No, I am not saying that you should drop your gas tank at all. I am saying this:

1. Read the document referenced in post #3 above.
2. After you have a good understanding of the IACV/ECU issues, repair the IACV/ECU problem by following the instructions in the document.
3. At this point, your P0505 should be gone. Check if you have any other codes - pending or outstanding - now that P0505 is gone.
4. If you still have P0302, take care of cylinder 2: spark plug, coil, oil contamination.
5. If you still have P1440: Add some moisture-removing additive(s) to your gas tank. Then follow the diagnostic procedure on page EC-627 of your FSM.

 

The symptons you have described match exactly what I've dealt with off and on periodically for the past 6-7 years. The issue seem to occur randomly, I can't figure out any kind of trigger but it generally only lasts for about 10-20 miles then I'll feel a slight jerk from the car and power is completely restored with everything back to normal. I can go another 100-200 miles sometimes longer without it occuring again. I was just wondering if your problems are periodic or all the time and if you do find a solution please reply with fix much appreciated.

I always attributed the symptons to some kind of blockage somewhere because of the length and randomness of symptons.... the car starts up shaking with loss of power.. I'll drive few miles... then poof my car hiccups then back to normal. I used to drive the car on low fuel a lot so I thought maybe fuel filter blockage but I'm not that mechanically equipped so just throwing that out there. Neglecting the issue is terrible I know and obviously this will be a good lesson learned but being poor and only driving the car about 4k miles a year it wasn't that much of an inconvenience.

Also, yes the check engine light has been on for years and no I've never checked the codes. Smart person would say start there but yeah I'll just ride till the wheels fall off.

 

Okay so I recently just replaced both front and rear valve cover gaskets the back was leaking slightly and the front was easy so why not.Also removed the upper plenum and replaced gasket along with my pcv cleaned a lot of brown gunk from the intake. None of these changed much but It's peace of mind knowing I've checked it all.

Now for my iac I cleaned out and removed as much carbon and replaced throttle gasket and did the idle relearn procedure. P0505 is gone and my idle is now 700rpms not 900, it was very easy to do (beware the iac Philips screws one of mine broke if you break the outer screw your still okay you can drill it out and use a nut/bolt setup instead)

Today I poked around my canister box and vent control valve and realized a very large split on the body of the canister box exactly where the valve body meets (btw I checked this due to the reappearance of p0455 and p1448 pending). Tomarrow I'm going to silicone the cracks possibly remove and test the valve I doubt I will judging it will likely break and need replacment on its removal.
Hopefully this will eliminate my p1440 and other pending evap codes.

As for the misfire though I beleive this was possibly cause by a rich condition (my hesitation/rough idle issue) as I've said all new coils, new plugs and should have no check engine lights after I fix the crack on the canister successfully. To me this all sounds and feels like my cats are clogged but I don't want to just throw a whole new exhaust on my car if this not my issue, any posts at all very much apreciated diagnosing tips ect

 

Like I posted previously my car has been running exactly like you've described for a while now but after replacing transmission fluid the check engine light has shut off and the car is now running like a dream. Could it be this simple? Probably unrelated but I thought I should post anyway sorry if this doesn't help.

 

I have not change my transmission fluid but it is still clean and is full.

Just recently the other day on my way to work..... It stalled on me twice if I was going about 50 and let off the gas the toms would drop like they should but drop all the way to 0 and stall.
After I **** the car off it would not stay running starts every time fires up and died instantly. I spent $250 on the iac assembly and installed it myself no problem, fired it up 1500 rpm idle so I performed the idle relearn without consult 2, started it up bam perfect idle 750 just like I've done it before hit the gas revved it to 3-4 grand to make sure it was going to idle right anddd it stalled as soon as I let off the gas and then maybe 1 out of 15 starts it would stay running but as soon as u give it gas and let off it dies, every other start up it would stall....
The next day I adjusted the idle screw, it got it running no stalling, has stalled maybe twice in 3 days now but the car is doing weird **** now. The car sometimes starts and idles good at 750 or it will be way up at 1500 it could go to like 1-1200 but will slowly work up to 1500 rpm idle lol I don't get it.
While driving, well it pretty much drives itself sometimes lol I don't hit the gas the cars at 1500 Rpms on a smooth road my car will just keep accelerating sometimes surge from 1-2000 Rpms as if it has no clue what it's suppose to be doing
The last thing I guess I can describe also is I. Drive it will be at 500 Rpms when it's running "okay"(still not right) and shake a lot of cabin vibration probably minor shaking from my old mounts but it just sucks

This is my daily driver and I can't be out of a car I cannot seem to fix this issue any help please

Also I've retried the idle relearn like 5 times each time seems to work but after you give it gas or restart it, it will go back to being high idle

 

Your car is stalling; and idling badly. Your title is misleading.
This class of problems typically happens because of: bad MAF, bad or intermittently failing CAM and/or CRANK shaft position sensor. And less frequently, for other reasons.

So, forget the idle re-learn. Besides, your car doesn't need it, just disconnect the battery overnight. I suggest you do the following:

1. Check for any (pending) codes. If you don't have an ODBC reader, get one like: http://="http://www.amazon.com/OBDII...odbc+ii+reader ($16) or http://="http://www.amazon.com/Actro...er: Automotive ($39).
2. Search this forum for "car stalls", in title only, then educate yourself by reading at least half a dozen selected threads.
3. While you wait for your ODBC reader to arrive, clean your MAF. The MAF often fails without throwing a code.
4. If the problem is still there, make a decision based on my suggestions above while considering any incomplete monitors or codes you get.

Good luck.

 

Ok my car no longer stalls anymore after I replaced the iacv assembly. I even put the old iac valve back in a week later just to see and sure enough the car would start and die right away so I knew that solved the stalling issue.

I scan my car all the time obd2 scanners on the back seat always lol. I realize my car has multiple issues with varying check engine lights. Currently right now it has p0440,p0505,p1440 but yesterday it was p0300,p0505,p0440.
The codes that constantly come up on my car currently in order are
p0505(always on)
p1440(almost always on)
P0455
P0440
P1448
P1490(rarely)

Not sure wher to start with I believe the p0505 and misfire are the cause of the misfire/shaking/high idle/low idle/idle surging I'm experiancing my car constantly changes the way it's running it could be misfiring constantly with VERY high idle1500-2500 cold or warm, shaking, hard shifting, surging in park or neutral 1500-2000 Rpms constantly, this is when I hate driving my car most.....

On the other side it could run good idle at 750 or slightly low at 600, in drive the car drops even lower idling at 500 Rpms (not normal at all) I sometimes get cabin vibration when it idles that low in gear can hardly tell the cars on but it's drivable and bearable like this.

I've cleaned my mass airflow a few times the MAF reads right in spec no fluctuations even when running rough.

Today my car was running "bearable" and I noticed when I was in park I could rev the engine a lot or slightly and when the Rpms were decreasing they go past 600 Rpms (where it idles at) to as low as 450 then come back up to 600. During when the Rpms pass 600 all lights dim and a pop/ click from under the car, sounds like an electrical component from under the engine bay. Not sure the cause of this.

About at the end of the line with this car any advice greatly appreciated.

 

P0505 is the one to focus on. The other codes (P1440, P0455, P0440, and P1448) are all related to your EVAP system and leaks therein; these can wait until you fix your P0505.

Have you read the document I gave you a link to? (https://drive.google.com/file/d/0B6O...fNlF5QjQ/view). If you did, then you should be aware that you have a problem with your IACV, and that your ECU was probably damaged, and that you should repair and then replace both at the same time. Have you done that?

You need to inspect your ECU and determine whether it has been damaged (I suspect it was). Next, you need to determine whether your IACV, which you recently replaced, is still OK or whether it was damaged by the bad ECU. Measure its resistance, as documented in many posts on this forum and in my note. Then, fix the faulty part (the ECU, or IACV, or both). Only then, after your are certain that both parts are good, replace both of them at the same time.

 

what did your ecm look like when you pulled it to check if it shorted?

 

I'm going to check my ecm soon when I get some free time I'll hopefully be able to share a picture of any damage to my ecu if found or noticeable. Also I have many videos of my car I'll try an set them up so I can link them here soon.

 

What brand coils did you use?

 

I believe they were hitachi? Both front and back

I replaced all six coils at once due to the cylinder #6 coil failing and causing my misfire/p1320 code.

Funny thing is #6 coil on my car was the only one that had been replaced and had failed before the other 5 original coils.

 

oh, i just assumed you had done it since it was highly suggested 3 months ago. if it were me i would start there

 

Okay so I finally pulled my ecm's out to take a look, pretty simple to remove 4 8 mm screws located in front and behind the ecm's bracket(probably need a flex head 1/4 ratchet or ratcheting wrench w/ a flex head to get 2 of them out) on the passenger side I had a plastic lever setup that holds the connector on the ecm and came right out. Removed the 4 Philips face plate screws on the ecm and sure enough it was burnt on the micraboard. The carbon spot I found was located right next to/touching the STA509A card,I would consider this a rather large burn about 5-8mm wide on one of the yellow power tracks also another burnt area on the opposite side of the STA card on a pin going into the card.

Seems like the iac related ecm issue guess I'll have send mine out for repair.

i got recommended to a ecm's repair place I forget where but seems like 200-300 dollar range for repair if repairable.
Any better suggestions??? Can I get it fixed and just throw it back in? Or do I need a rekey

I was also told there's about 6 ecm setups for my car all 6 have different keys. Could I find my same exact ecm, get it rekeyed to my car and then throw that in? If so I will def take this route seeing as I can get a junkyard ecm for $35 and pay for a rekey about $100-$150.

Not sure if I'm going to fix my baby she still needs a fair amount of work exhaust y pipe and back,2 front control arms, and a radiator support.

If I can find s reasonably priced ecm situation **** it I'll do that, put control arms in this ***** myself , strait pipe w/ muffler, and just forget about the radiator support I welded her in place

 

junkyard ecu + nissan datascan II

 

This document https://drive.google.com/file/d/0B6O...1fNlF5QjQ/view contains several references for where to repair your ECU.

 

ended shipping my Ecm to speedometerrepairguy.com only costs $85 for the repair.
Worked out great fixed the p0505, starting/stalling issues,very low idle, very high idle, and intermittent surging idle. They put a warranty void sticker on the edge of the ecm so I can't see the work they did to the micraboard without damaging the sticker... but it's nice knowing their is a warranty on it.

However my drivability issues are multiple problems. Now my ecm is repaired but I still have p0300,shaking(most noticeable idling in gear,neutral dampens most of the shaking, VERY poor acceleration/hesitation.

My next move is to put headers and a cat back on asap because likely this is all from my nightmare stock exhaust 155k on it, it is currently without a muffler, leaks over the axel bad, resonator leaks small, and my manifold is leaking bad as well...took it to an exhaust shop they said the misfiring is likely from the manifold leak with a clogged cat possibly or "feels like".

Is this a fair assumption to remove my manifolds and replace with headers/cat back. If so more than willing to fix this last issue on this max.