deezo

iTrader: (3)

Started last week and continued to happen during my trip up to NYC and back.

Searched the threads and it looks like one person had this issue but got no good responses.

If I shut the car off and back on, the engine idles as it should. Which sensor should I be looking at for replacement?

I thought about replacing the TPS because my idle would drop very low when slowing down to take turns. At this point, I don't want to throw money at the issue since I just bought 3 coil packs.

Any help would be appreciated.

njmaxseltd

iTrader: (19)

I'd be looking at the IAC valve. Clean it up, make sure it's moving freely.

max ride 41

iTrader: (4)

cleaned your maf lately?? i know my max was doing this and i did a maf clean and injector service and now pretty much ok. ( i have original coils with 260,000 on them )

cool

What's an IAC valve and would you kindly point where this is located?

njmaxseltd

iTrader: (19)

Idle Air Control Valve - Next to the throttle body.

Maxima 97 SE

The idle air control valve has gone bad. That's why the car idles high when it's hot is because the valve is not working is and is getting stuck sometimes and when you turn it off it the high idle stops because the computer resets. The same thing was happening to me so I'm talking from experience.

max ride 41

iTrader: (4)

i replaced that with an oem one at the dealer 5 years ago and i get that high idle rev when she's hot and i step on the gas and it does'nt kick down until i put it into gear. i found out from searching online that the part that might be bad within or connected to the iacv is called an 1639131U00 - thermo element kit. it goes bad and causes the iavc to rev high when hot. hope this helps.

deezo

iTrader: (3)

Hmmmm, funny thing is I got this one from a low mileage engine Zack had when I was still living in Boston almost 8 years ago. I cleaned it up and put it on the car at the end of Summer last year.

I'm going to grab the original one out of the garage, clean it up and slap that one back on.

Thanks for all of the replies guys.

deezo

iTrader: (3)

So it looks like one of the sensors on the used IAC must have gone bad. Cleaned the hell out of it and it still had the occasional high idle. Took the car back to the house, got my original out of my junk pile, cleaned the fark out of it with some throttle body cleaner (outside) and MAF cleaner (inside).

Took the car back out and drove around Raleigh since it's a beautiful night for a drive and the original IAC is working as designed. It never had an issue in the first place but I thought replacing it with the one I got from Zack would have helped with another idle issue I was seeing last year when I cleaned the engine.

Anyway, all is good now onto the next issue.

The Wizard

iTrader: (43)

Good to hear. And glad it turned out to be a free and easy fix.

deezo

iTrader: (3)

UPDATE:

I spoke to fast. The problem exists even with the original IACV. Time to look at something else. I'm checking the FSM but if anyone seems to have any leads, please feel free to respond.

Thanks.

max ride 41

iTrader: (4)

look at post #7, good possibility as i have the same issue from time to time.

deezo

iTrader: (3)

I'll look into it.

The only thing that makes me think it's not the IAC at all is the fact that I used 2 different ones and still have the same issue.

I'm seriously leaning towards the TPS. Hell, the car has 374K on the clock so I won't be surprised if that's somehow has gone bad.

jholley

iTrader: (13)

With the engine warmed up does the throttle plate close and sit flush against the stop screw? If not then as previously stated the thermovalve within the TB's fast idle CAM isn't working. The thermovalve is part 16391U in this diagram.



If so then try another TB.

deezo

iTrader: (3)

Not sure if it sits properly so I'll have to check when I have time and light. When I shut the car off and start it again, it resets and the idle goes back to normal.

Ok guys, I'll follow your lead. Thanks for the schematic also.

jholley

iTrader: (13)

If the throttle plate does close when the engine is warmed then use this procedure to revise the TPS

http://www.lyberty.com/car/Maxima_A3...NTB99-053b.pdf

max ride 41

iTrader: (4)

here's something i did last december that almost stopped the issue altogether, i went to the dealer and had a re-learn done to the ecu. it helps set all the throttle positioning and idle etc back to factory spec and also helped with my gas mileage. i know you have higher mileage than me, so a part wearing out isn't out of the question.

deezo

iTrader: (3)

I will give it a try. Thanks for the doc.

max ride 41, I've read where people did the relearn for idle issues but it seemed to be a waste of money and time. When was the last time your idle wigged out after the relearn?

max ride 41

iTrader: (4)

i just did it in december and it doesn't do it now. after it gets hot it might jump up in the rpm's but pulls back down to proper idle almost immediately. i also did a seafoam and an injection service and car seems to run fine most of the time. my plugs were new 6 months ago, as well as my fuel filter and a new k&n air filter. maybe do a tune up and scan for any codes and see if the idle screw can be adjusted a little as well.you might need to replace the iavc again, hopefully not.

deezo

iTrader: (3)

Tune up already done this past weekend.

Took my kids up to NYC for their spring break and the car was running like crap in traffic. Was getting misfires because I left the copper plugs in too long being lazy.

Cleaned my drop-in K&N, MAF, IACV and throttlebody. Also made idle adjustments.

I'm going to run the test on the TPS and see what I find. Driving the car today, it didn't give me one problem with idle so whatever it is, it's not constant.

max ride 41

iTrader: (4)

and if it aint broke, don't fix it.

deezo

iTrader: (3)

Yeah but I think it's the TPS wigging out. I've had 2 different IACVs on the car and got the same issue after.

deezo

iTrader: (3)

Have noticed that when it's warm out, this issue doesn't happen? Here in NC, the temps got up to 80 over the weekend and I haven't seen the issue since. Temps haven't dropped below 70 since the weekend during the daylight hours.

max ride 41

iTrader: (4)

my max had been stuttering in reverse as of late. i gotta check the trans fluid and scan for codes. any ideas on that?

deezo

iTrader: (3)

Sorry, I don't have anything but I can tell you that I swapped the EVAP purge control valve with another one and it seems my idle issue has stopped for now. I'm keeping my eye on it.

Now completely clear on why this would have caused an issue but the car is definitely reacting better.

NmexMAX

iTrader: (22)

Damn deezo, still got the Maxima. Awesome!

deezo

iTrader: (3)

Most def. I'm going to cry when this car dies.

I still drive it everyday and when I head up to NYC. I won't take my G8 nowhere near the northeast with how bad the roads are up there.

jholley

iTrader: (13)

Keep your eyes open because that valve has no effect on idling.

deezo

iTrader: (3)

Ok thanks. It was something I replaced when I replaced the IACV initially but I decided to swap it back. I understand what the Evap control valve is supposed to do but I'm wondering if it somehow was malfunction and causing the high idle. I'll keep checking things though.

deezo

iTrader: (3)

I think I found my issue. I adjusted my throttle cable back earlier this year since there was some slack in the cables. I should have just left it alone since nothing was wrong but I thought I was doing something by being proactive since I was bored and my kids weren't here.

I decided to check some things and I noticed when I touched the outer throttle cable, my idle shot up.

My motor mounts aren't the best they can be right now so I think what's happening is the motor is moving based on the shock transmitted from the road and when I come to a stop, the cable is in a position that's making the car idle high. I turn the car off and turn it back on, the vibration from that makes the cable sit correctly. I had the tolerance of this throttle cable to be very sensitive. Soon as I backed off the this tight tolerance, the high idle issue stopped. When I touch the cable, it doesn't raise the idle at all now.

I'm going to keep my eye on this but I think the problem is resolved.