I want to pull the throttle body off to clean out the 200k+ miles worth of grime in it.. I want to know if I need to order a gasket in advance or will I be able to re-use the existing one? The reason I ask is that the "common parts" section of SE-R.net lists a throttle body gasket for the 200sx only.

There is a good chance you will tear it. Especially after 200k. Mine tore and I only had 40k at the time.

I was thinking about taking out my tb to clean it some day. Tell me how it goes, what kinda problems u run into, stuff like that.

they are like $4, my question is why not??? I know that is a beer at the bar, but dang :)

yeah yeah.. i thought it over and then just ordered one. better safe than sorry, especially when we're talking less than $10.

Scarpa, please let me know how well this goes on a high-port. I need to do this as well.

I'm very interested also.

Well, I remember when I did mine it wasn't actually all that hard. You just have to pull off all the intake stuff, disconnect the throttle linkage and the tps sensor, disconnect the two coolant lines on the bottom of the TB, then you can simply unbolt the throttle body. The throttle body bolts are hex, and you should go ahead and buy a new gasket (certainly don't want an intake leak before the maf, which would cause your car to run lean...)

There was a lot of built up oil gunk in the bottom of my intake manifold, and i used carb cleaner and rags attached to long extensions to clean it out.

Assembly wasn't too bad either, but watch out for those two coolant lines on the bottom of the throttle body. They are easy to disconnect, but a bitch to get reconnected because its really hard to get a grip on them.

Aaron
'91 Sentra SE-R, rice cooker #1 :)

Is there any merit in de-gunking more than the TB plate and bore - as in down into the intake manifold?

I've always just removed the intake hose and cleaned the area around the throttle plate, and used a small mirror to see.

I don't think it's worth it (cleaning any more than just the TB).

Also, if you use strong degreasers, they'll eat up the intake manifold gasket.

Ask me how I know this...

However, removing the TB to clean it does a much more effective job than you could ever do cleaning it while it's on the car, in a highport.

I left my TB on when i cleaned it. It still got nice and clean. I just shot some nice strong carb cleaner in there and scrubbed real good. :) No it didn't hurt anything. I thought I was going to have to take it off though, so I did buy an extra gasket and now have it sitting for a rainy day.

Same here, left it in place and used a small brass brush the size of a toothbrush to clean it. The brass was soft enough not to scratch the aluminum bore and did not fragment any pieces into the TB.

Gumout, a rag, and the small brass brush.

I did have to clear out the one vacuum port that goes straight down since it was getting sludged from the cleaning.

I am interested in the procedure for removing the TB from a high-port. Anyone have directions written up? I hear it's pretty easy, but it sure doesn't look it.

I always thought of the throttle body as the whole intake plenum. Now that I know this is just the throttle plate area, I have the same question as Jim. I would think the intake manifold should be pretty clean. The throttle body is important for idle and stuff, yes, but for performance one would think the intake manifold should be nice and clean. ???

Well, since my DET motor was out, I took off the entire intake assembly to clean it.

1. The gaskets on the intake are metal, so how in the hell could you destroy them?
2. The intake runners/valves were not that bad.
3. The intake plenum where the TB attaches was absolutely horrible.

http://www.sr20de.org/images/images/Sentra%20SE-R%20%28Classics%29/open%20throttle.JPG

http://www.sr20de.org/images/images/Sentra%20SE-R%20%28Classics%29/P3290013.JPG

http://www.sr20de.org/images/images/Sentra%20SE-R%20%28Classics%29/intake%20runners.JPG

When I did my cleaning I had to reset my idle. No big deal.

Steve

Ok I did do this, but I haven't driven the car yet since.

Taking the TB off was pretty straightforward, but a PITA. I started by pulling all of the intake piping out and disconnecting the throttle linkage. You're left with 4 allen head bolts holding the throttle body onto the intake plenum and two coolant lines running into the bottom of the throttle body. The coolant lines are a b!tch to get off and I personally spilled coolant all over.

Anyway, once I got the TB off I cleaned it up with carb cleaner. I also cleaned out the intake plenum some with carb cleaner but if you do that be careful. A "friend" of mine shot the little red straw from the carb cleaner into the intake, luckily it was a high port manifold so the straw just sat there until we stopped cussing and figured out how to get it out.

Installation is the reverse of removal. I didn't bother bleeding the coolant, I will find out when I drive the car if that is going to come back to bite me or not (did I mention I don't like working on cars?).

Idle is higher than it was before, that's all the feedback I have so far. After I drive the car I'll report on any improvements but I doubt I'll notice anything as I only drive the car for autocrosses and track events anymore.

I always thought of the throttle body as the whole intake plenum.

I thought the same exact thing!!!

Now that I know exactly what the throttle body is, I just removed it and cleaned it.

It's not terribly hard, but the coolant lines are a Bi-yatch!! Also, I had a vacuum line attached underneath that was also a pain. Did anyone else, or am I the only one???

In any event, it was rather dirty but is not anymore. I even took some brass cleaner and cleaned the brass plate (throttle plate??). Anywho, it's purty. The opening to the intake plenum was fairly dirty so I cleaned that as well. Inside, the intake itself looks pretty good from what I can see.

I'm off to the $tealership for a new gasket (mines not metal, must be different for the DET). And then I'll hook it all back up and report back.

The intake manifold gasket is metal, but the TB gasket is paper. I messed mine up on a Saturday once, and I went to AutoZone to see if they had one. They didn't, but they had a 8 1/2" x 11" sheet of paper gasket material for $.69. It has enough to make 10 gaskets.

Nissan didn't have any, but they could get one...on Friday :(

So I made one out of gasket material I had laying around.

The butt-dyno doesn't detech anything, but is used to miss every now and then while idling. So far I haven't detected anymore misses, but it's only run for 5 minutes since the cleaning.

The coolant hoses are a major pain in the ass. Better have small hands to do this.