i just cleaned my throttle body and there are no significant improvements. i used the valvoline carb choke & throttle body cleaner, like the one metioned in a earlier post. i have a 99' auto gxe. the idle does increase about .1-.2k rpm. i was able to get some gunk/deposit out of the body so it wasn't a total waste of time. the inside of my throttle body was relatively clean.

 

Your car must be young. Like 20 to 40K miles?? I cleaned my TB for the 1st time at 120K miles. BIG differnce. Every time I start my car, I KNOW. Jumps to 2000 rpm like never before. Then settles to 1500 and goes lower as it warms up.

DW

 

Same with my 98 Auto w/ 52k. Every time I start it, I'm glad I cleaned the TB. Much smoother in all aspects.

 

Another thing is....

It take no more than 20 minutes and costs only $3, so why not do it? It can only help.

 

don't buy the generic PCVs. Spend the money on the OEM ones. I know people who bought PCVs from Pep BOys only to see it clog up in a few months.

 

You guys are quite the salesmen! Because of you, I put 'Throttle Body Cleaner' on my X-Mas list. Although I probably would have chosen the Valvoline myself because of what you guys said, I forgot to specify that on my list. Well, just by luck, that's what I got! O.k., so I attacked this little project today. It took about 1 - 1.5 hours going very slow. I pretty much agree with the instructions on motorvatte.ca. but I experienced a few differences.
For starters, I did not remove the air filter/air filter box from the MAF. I simply unclipped all four clips and left it all in place. And then when it came to removing the small black rubber hose, it is a lot easier said than done! That little bastard was stubborn! I had to use a flathead and slowly pry it off. Then on the last step where is says "Remove the bolt as shown by the white arrow.", I don't have that bolt! And, in fact, I have one on the other side of the air filter not discussed. Anyway, no problem. Off came the whole assembly. Now looking inside the TB, it wasn't really as dirty as some of you made it out to be. And I have 125,000 miles too! I proceeded to soak the throttle body with the valve closed and clean the best I could. Then I was about to clean with the valve open by myself but my mom made the mistake of walking into the garage at that exact moment. So I told her to grab a mag. and sit in the front seat with her foot on the gas. Thanks mom. I soaked it, used a rag, used a toothbrush, soaked some more, etc., etc. until it was clean. I felt bad because I felt like I was spraying too much into the engine. I hope that's o.k. Also, I felt like I couldn't get far enough back in there with only my hands and toothbrush. Hopefully I did. Like, I said, there was not much. My rag was partially black but not completely black. When putting it back together, I didn't have any problems until trying to get the black accordian hose with the hose clamp over the throttle body. It was like putting an oval over a circle. It was driving me nuts! I eventually just had to use a flathead as a 'shoehorn' and that worked. I started the car and it wasn't happy at first. He hesitated, was rough for a second, made a few extra sounds, but then it was fine. I haven't driven it around but I don't presume I'll feel a difference. The idle was no different either. My idle has been really smooth ever since my G-Force ECU anyway. Thanks
guys for the inspiration.

 

next time,heat the hose up with a heat gun or hair dryer. It's easier to put back on when it's warm since it's more pliable.

The stumbling after cleaning the TBs is normal.

 

Just finished cleaning TBV on my 99'se. It was pretty filthy.Lots of buildup cane out.Havent taken it out for a drive yet, but I can notice a smoother idle.Took about 20 minutes to complete.

 

In the how to do on www.motorvate.ca it said to hold open the throttle wide and spray it in. but the guy at AutoZone said for me to make sure I complete dry it. If that stiff gets in the engine it will take out all the sensors. Is that true? If so, then what does it mean by “. I hold the throttle wide open, spray in the cleaner, and scrub the throttle body with my tooth brush”.

 

To the side of the TB you'll see two cables connected to a semi-circle lever. Pull that back and it'll open the valve in the TB which then allows you to clean inside the TB also. Open the valve and behind the butterfly plate you want to clean in there. Do it and you'll understand.

It's ok to spray the stuff inside, that's what it's made for. Just make sure it says that it's safe for Fuel injected engines. Others will warn you if they aren't.

 

On older carborated engines I know you had to be carefull because too much in could mess up some things. I dont know if that still exists today in newer engines like ours.

He opens it so you can spray behind the metal pieces that would be blocking it. This way you can get a good scrub of the whole area.

SuDZ

 

The Nissan PCV valve is good for 100k miles I believe DBM said once. So if you do swap it out you will not have to worry about it for the rest of the time you own the car most likely.

SuDZ

 

i cleaned the throttle body in my '95 a couple months ago and the throttle body cleaner i used said to spray with the engine running in ten second intervals so you don't risk damage to your catalytic converter. i don't see a "complete" cleaning by just holding open the butterfly and wiping only what you can see.

 

So you had the car running and pressed the gas pedal down and sprayed it in then? Just surious if you were doing this is if was open just enough to spray in or if you were letting the car tach up kinda high?

SuDZ

 

i cleaned it with a rag and the engine off first to keep at least some of the carbon build-up from running through the engine and exhaust (i'm not sure if this matters, but ...). then i sprayed with engine running while tugging on the throttle lever.

 

hey SuDZ, what exactly does the PCV valve do anyways?

 

after i cleaned mine, i got 2 more mpg!

 

Was wondering if I can clean my throttle body as per the instructions above during winter outside?

Shoud I warm up the engine? Any tips?

Thanks guys.

LEfty

 

NO need to warm it up.

Yes you can do it outside when its cold - it only takes 20 minutes.

Start with a Haynes manual and Motorvate.ca and if your still having trouble let us know.

 

engine should be off. If the intake piping is off and the car is running, it'll stumble and probably not keep idle.. shutting off.

 

like i said earlier i did it with the car running (per the instructions on the label) and it didn't come close to shutting off. if it stumbles a bit during spraying just give it a little gas. if you'd rather do it with the engine off then stick to the instructions on www.motorvate.ca

 

I'm not sure if this is related but after I cleaned my throttle body, my idle occasionally stumbles when in drive(Auto). The idle is about .5-.55K RPM. Have any of you noticed this? or and ideas.

 

I have the exact same occasional problem. I cleaned the TB last weekend and that took care of the cold start problem, but it did not cure the idle variance. My guess is to adjust throttle cable and check the PCV next, that's easy. I have checked the ECU and there aren't any error codes.

 

I've never cleaned mine and I'm ast 112k..

 

If you have crazy idling you might want to do a search for Idle air control valve (IACV). This might be the cause of your problem.

 

Join the club! I cleaned my TB for the 1st time at 120k miles

DW

 

So did you really notice any difference or did you just feel better knowing it was clean??

 

Big difference. When starting up from cold, my car used to just go to 1500 rpm. Now it JUMPS to 2000 rpm then settles to 1500 rpm. Light throttle movement is much better and responsive. My idle when warm has gone up like 200 rpm as well. It was at 600 rpm, now its at 750 rpm. I really didn't think much of this maintenance item, but I'm a changed man now

DW

 

Sorry. I did not see you until now.

The PCV valve does exactly what it's name suggests, it provides "Positive Crankcase Ventilation". So if the pcv valve gets clogged then it won't provide proper crankcase ventilation which can cause numerous problems including: severe oil leaks, damaged gaskets, and excessive emissions

SuDZ

 

i'm at about 108K. in addition to cleaning the TB, I also adjusted my accelerator cable and actually removed the TB to clean behind it.

i used some generic TB cleaner from autozone. worked well. the butterfly value was easy to clean, and it was quite dirty. i used rags to clean the butterfly valve.

after removing the TB, cleaning behind the TB was more difficult. since i couldn't get my hand in too far, i sprayed a toothbrush and only cleaned as far as my hand + toothbrush would reach.

as far as results go, i do notice improved throttle response, but i'm not sure it's because the TB is clean or because my accelerator cable has less slack.

if you remove the TB, don't forget to put in a new TB gasket.

 

How do you adjust the cable? I was looking at it but was not sure about this. Also How do you know if it has too much slack in there in the first place?

SuDZ

 

Have someone sit in your car, and with the engine off, have them floor the accelerator. You, meanwhile are looking at the throttle body while they are doing this. If, when the accelerator is floored, the cable does not go all the way to its bump stop, then you have too much slack. Keep in mind, Maximas, as well as most cars, come from the factory with some slack at throttle tip in, but they still open the throttle all the way when floored.

DW

 

But how do you actually adjust it from here? I tried taking a look but could not find any adjustment screws or anything.

SuDZ

 

Perhaps I should answer the question,

Anyways, you adjust the slack in the cable by loosening the 2 nuts at the end of the cable. I haven't done it in a long time, but you basically 'move' the 2 nuts forward or backward, depending on how much you want to loosen or tighten the cable. Once you're done. tighten the 2 nuts against each other so they stay in the new position.

DW

 

Oh ok. So by lossening one and changin the length that will adjust it. Okay now that I remember what it looked like that makes much more sence.

Thanks

SuDZ

 

i hope those tires and wheels are fake because they look awful!111

 

it only happened one day, so far 2 straight days and its ok again.

 

Do autoshops clean throtle bodies? I am too lazy to do it myself, and they can probably do a better job.

 

I think Nissan clean them for $170. It says it in an earlier post.

 

I copied the following from a DBM answer on another thread.
**
When properly adjusted there is a small amount of slack in the cable.

Accelerator cable:
a) Lift up on the cable to remove any slack.
b) Turn the adjusting nut until the throttle lever starts to move. (The adjusting nut is the one further from the air intake).
c) Back off the adjusting nut 1.5 to 2 turns.
d) Tighten the locknut (the other nut).
e) Verify that the throttle valve opens all the way when you depress the accelerator pedal to the floor and that it returns to the idle position when you release the accelerator. Verify the cable operates smoothly. It must not bind or stick.

Cruise Control cable:
a) Check the accelerator cable for proper adjustment.
b) Turn the adjusting nut until the throttle lever just starts to move.
c) Back off the adjusting nut 0.5 to 1 turn.
d) Tighten the locknut and check for proper operation of the cruise control system.

For photos, please see the Haynes repair manual, page 4-6.
** end

Breaux124: Thank you for the idea. That's on my list after the PCV valve replacement. I adjusted the cable yesterday and as I suspected it didn't fix the problem. You're probably right, it's the IACV.
But, I like to try the easy fixes first