Hey Orgers...yesterday I cleaned the throttle body and changed the plugs on my 98 Max. I used CRC air intake cleaner, and NGK Plats. I cleaned the throttle body as indicated via this link http://www.motorvate.ca/mvp.php/518 and started the engine to burn off any residue of the cleaner.
I didnt take note of any high idle then due to the engine being cold, thought it to be normal. After shutting it down after 15 seconds or so, I changed the spark plugs. It now idles in Park around 1000 rpm when the engine is at operating temperature. While in Drive and at a stop, the engine idles at around 600 or 700 rpm..., not sure if this is right or not. Thanks in advance for the credible input.

 

hey metal god, i just cleaned mine a week ago and i experienced the same effect. I let the car run for about 5 minutes or so though, and it eventually dropped down to normal idle rpm's. try letting it run for a little to see what happens, i was scared at first also..

 

the problem is when you follow those bad instructions you usually end up cleaning only part of the throttle body. not only that, but when you spray it you usually end up spraying the stuff off of the throttle body onto the IAC Valve. the only proper way to clean it is to take them both off and give them a good cleaning.


PM sent to both of you and dont adjust anything as a good cleaning will return things to where they are supposed to be.

 

I prefer the higher idle but thats me....u might need to adjust it the TPS....if it doesnt correct itself

 

Is adjusting the TPS the only way to adjust the idle?

 

you adjust the idle by turning the screw on the IAC Valve.

 

man it is normal. you guys are on crack.

but yea. cleaning the entrance of air isn't going to allow more air flow into the rest. You gotta clean everything up nicely. wire brushes and stuff.

 

Normal while the ECU resets itself. Give it time and it should drop back to normal rpm.

 

I did a similar job, and had the same results. Im not a big fan of spraying the cleaning stuff directly on the the throttle body, it could leak down. I would rather spray the stuff on a rag and clean wit the rag.

No offense TurTLe*, but if u need a wire brush to clean ur tb, i think the car would be having problems.

Since i have owned my car, the idle has been at 900to1100 depending on the circumstances in park. in drive, its like 650-750. the idle sounds about rite.

Also, next time u clean the tb, lift the butterfly and only use the rag to get wat ever gunk u can from behind it. every little bit helps.

 

Thanks fellas, you guys been a lot of help, especially Mizzax... I also failed to mention in my previous post that I id reset the ECU ( have had a KS 0304) and adjusted the throttle and CC cables.... WHen i took the car for a ride dow the road after cleanign the TB and changing the plugs, I noticed the high idle.......thought it was the throttle cable being having tension on it at rest, but I checked and it had enough play, so thats not the problem. I thought about it being an ECU adjustment period...but not so sure.

 

Also there is a noticable power increase, the old plugs were tired....made a difference in low end torque...

 

I haven't had a chance to clean the IAC valve yet, but have noticed over the few weeks that the mileage isnt good at all. The car used to get 25-27 mpg, now since I cleaned the TB and replaced teh plugs, its only getting 21mpg.
I contacted the Nissan shop that I get parts from, and was told by a credible source in service that it needs a download, even after the ECU being reset. Any feeback on that?

 

Just took the IAC off and cleaned it...still have a high idle of 1100 RPM in park. Anything that I might have missed or not done properly? I removed the AIC and cleaned the brass piece on both sides.

 

the idle isn't a big deal IMO. It's not out of control and if it idles around 750 in drive than it should be fine. What's the problem? Is it effecting the car?

 

its not a huge problem, but I know that it isnt right.....and it changed to this high idle just after cleaning the TB. I'm wondering if there is something else that should be done to clean in the IAC that I might have overlooked.

 

well usually after the TB cleaning the idle will rise, it has been cleaned....Most guys said that the idle dropped after a while. If it doesnt then adjust the idle stop screw and maybe check the tps.

 

Hmmm..yeah, I've thought of adjusting the idle screw, but am hesitant to just mask a problem if it was fine before I cleaned the TB. I called a tech at the Nissan shop, and was told that a new download is entered in the car to correct that.. I havent heard anything such as that before....
About the IAC valve.....I took teh brass piece off and cleaned the inside and outside of it. What else coudl I have missed on cleaning it thoroughly?

 

Is the part thats inside the IAC valve body cleanable? I unscrewed teh brown plastic part on the end with the electrical connector, and found a small spring with a metalrod. I assume that moves back and forth, but would that need to be taken out and cleaned to solve my problem?

 

i just cleaned my TB and replaced my KS as well and have the same thing.. idle around 1000 in park used to be 650 ish

 

Thats normal, you think about it, ur TB was so dirty it didnt breath right so it was around 600ish now that its clean. its got more life..

 

Don't adjust anything. The idle will return to normal in due course. I had the same probem and it went away after awhile.

 

It's probably just the TB cleaner that you used getting sucked in and burned up. Idling takes very little fuel, and just a little bit of solvent in the intake will noticeably rev the engine.

 

I just had my throttle body, maf, and iacv cleaned a few days ago and now i idle at around 1k in P and N warmed up. When it's D, it will idle at around 900 then fall to 750 after about 5 seconds (happens everytime i come to a stop). I'm assuming in due time it will go back to normal, but how long will that take? A few weeks?

 

can someone post a picture of this IAC valve i duno what i am looking for in the engine bay

and how do i adjust my idle ? its too low at around 575 rpm in drive at normal temp

 

its towards the bottom of the page...

http://forums.maxima.org/showthread.php?t=512892

 

there r 5 electrical connectors on the iac assembly that i see, the instructions to adjusting the idle say to :
warm the engine
turn off the engine
disconect the TPS
turn engine on
adjust the black screw until the rpm is exactly 650rpm (is this the standard for a 4th gen?)
then turn engine off and reconect the tps

which conector is the tps ?