The Full throttle body cleaning write up.

[2kredz3]

Okay as promised here it is with full color pictures.

Step #1

Remove the stock air box, it is a 10mm nutt holds it to the chassis and two hung clamps hold it to the MAF sensor.



Here is what it looks like with the box removed.


Step #2

Remove the MAF sensor and use some spray cleaner to clean it. i chose to use carb and throttle body cleaner, the important part is to make sure that you use one that says it will not leave a residue. the MAF sensor is held on by a hose clamp at this point. a flat head screw driver or a 6mm socket will work to remove it.




^^^ you may notice that yours looks different then the one above (yours will have a grill on the back of the sensor intake side.) we chose to take this out for testing. since we have already removed all the other baffles in the intake on this car we thought we would remove that one as well.

Make sure that you dont let the cleaner siton the wire in the middle (spray and shake)



Step #3

the next section is all about taking the intake tubes off the throttle body. You will notice that there are two sections of tubes. the lower tube (connecting to the TB) also has a small tube that goes to the intake (i suspect that this is for the idle air or something like that) what we found was a little shocking and i suspect that this is a problem on a lot of Z's because of the design of this joint.



as you can see the smaller tube is split. we will address that before we put it back together but on a sunday there is no chance of getting a replacement part so we had to make due.

this pic is of the lower tube and you can see the small tube branching to the right. also note how dirty the tube is.



using the 6mm socket we also took all the hose clamps off.



Step #4 taking the throttle body off.

there is a wire harness that is essentually and completely in the way. there is a bolt (10mm) on the left side of the wire harness. on the top side there is a 10mm nutt as well as on the bottom.



once you get the wire harness un bolted there is a plug that will limit its movement, the plug is a sensor that plugs into the intake manifold it has the same type of clip that the MAF sensor has so just un do it and pull it back. you will be see the throttle body now.

there are 4 bolts (10mm) that hold the throttle body to the intake manifold. they have a low low tq setting so dont bust your knuckles in that tight space. you will have to work with the throttle body to get to the linkage, it is just one wire from the pedal to the throttle body. you simply open the throttle body plate all the way (or have someone do it from the inside )once it is open hold it open and let go of the pedal the wire will go slack and you will be able to pull it off the linkage. then on the lower left hand corner there is a large plug for your DSC control it spins counter clockwise to release.

step #5 cleaning



^^^^ notice the white arrow on the lower left side plug, remember that as you will be lining that arrow up with the same white arrow on the wire harness in the car when you put it back together.

perffferred method for cleaning is dish soap and a scotch bright pad (used for cleaning dishes.)

more pictures of the dirt:




this is the intake manifold from as close as i can get my camera. . .i will be pulling that off to figure out how to clean it someday.

[2kredz3]

This is the repair to the tube that was cracked, we used RTV sealant (black is high temp) its basically a rubber gasket maker that stays rubbery.



Here is what your Throttle body should look like:




after looking at these pictures i am also going to figure out how i can polish that throttle body.


Rember the white arrow i told you about. . .here is the pic that shows the wire harness end. . .once you get the harness back on and screwed together the white arrows will line up. . .




Start putting it all back together the way it came out

Clean Throttle body re-installed:

[mrnvgtr]

2kredZ3 - please link or post this to the DIY Writeup sticky thread. This was very well done. Thank you.

[2kredz3]

2kredZ3 - please link or post this to the DIY Writeup sticky thread. This was very well done. Thank you.

just linked it to my sig. i have the original one that i did (last year) in the DIY thread already

[jameswbl]

i wouldnt touch the MAF sensor if its functioning normally...coz there are many case where ppl screwed up and its very easy to break those wires...

its $$$$ to replace...

good DIY though

[2kredz3]

i didnt say touch the wires but you can clean it just like anything else. . .besides if you dont clean it you WILL be replacing it sooner rather then later

[Ghery]

I did this a few days ago

Everything was pretty clean, super clean for the car's mileage.

But I took the ICV and cleaned it out, it was filthy and caused idle issues.

While you have the TB out, might as well remove the DISA unit and take out the ICV and clean it out.



Thanks for the write up 2kredZ3

[Z300991]

I would not use any carb cleaner since the sensor on the MAF is sensitive to different chemicals and dirt.

I use CRC MAF cleaner on all my cars and it works great without issues.

Regards
Alexander
+=FUN

[Robstah]

That engine looks like a pain in the ass to work on...

[2kredz3]

I did this a few days ago

Everything was pretty clean, super clean for the car's mileage.

But I took the ICV and cleaned it out, it was filthy and caused idle issues.

While you have the TB out, might as well remove the DISA unit and take out the ICV and clean it out.



Thanks for the write up 2kredZ3

np, where was the ICV on your car? is it mounted in the tb itself? didnt even think of that because i am not having trouble with it.

That engine looks like a pain in the ass to work on...

it is. . .but once i do the m50 intake manifold swap it wont me

[bmw_e30]

np, where was the ICV on your car? is it mounted in the tb itself? didnt even think of that because i am not having trouble with it.





it is. . .but once i do the m50 intake manifold swap it wont me

Soundofspeed posting:

ICV is on top of the TB under the manifold, big polished metal thing.


M50 manifold is a mod for single vanos motors, won't work right on yours. That box to the right of the manifold unit is the DISA unit. It's a flap that manages airflow in the manifold. Your DME deals with it, so M50 manifold won't work.

[2kredz3]

oh, that is gay. . .i thought that it would work and had seen it on some 323i's but i guess i didnt pay attention to the year

[Ghery]

oh, that is gay. . .i thought that it would work and had seen it on some 323i's but i guess i didnt pay attention to the year

You have the option of doing M54 manifold. 60% of power different between 2.8 and 3.0 is the manifold.

I almost bought one, but my plans at the time kept me front it.

[Robstah]

You have the option of doing M54 manifold. 60% of power different between 2.8 and 3.0 is the manifold.

I almost bought one, but my plans at the time kept me front it.

Why do people keep saying that M50 and M54 manifolds provide more power? All they do is shift the power band and you lose torque.

[2kredz3]

You have the option of doing M54 manifold. 60% of power different between 2.8 and 3.0 is the manifold.

I almost bought one, but my plans at the time kept me front it.

I will start looking into that, will it bolt right up?

Why do people keep saying that M50 and M54 manifolds provide more power? All they do is shift the power band and you lose torque.

It may just shift the hp and tq up but that would be a major help on my car as it falls on its face from 5k-6k rpms

[Robstah]

It may just shift the hp and tq up but that would be a major help on my car as it falls on its face from 5k-6k rpms

Cams.

[2kredz3]

From what? I have heard that i have an odd ball engine. so some say i can put m54 (3.0) cams in but then some say that i have to put s52 cams in. . .im confused on that, so if you know which ones that would be great.

[Ghery]

Why do people keep saying that M50 and M54 manifolds provide more power? All they do is shift the power band and you lose torque.

Well the double vanos manifolds are different.

M50 manifolds provide more flow, and you lose a little down low.

M54 manifold provides more flow so you gain up top, but it also has a big DISA unit so you gain torque too.

[Ghery]

From what? I have heard that i have an odd ball engine. so some say i can put m54 (3.0) cams in but then some say that i have to put s52 cams in. . .im confused on that, so if you know which ones that would be great.

You can't put single vanos cams in.

M54 cams will work fine, but I don't know how much you'll be gaining and if it's worth it.

[2kredz3]

You can't put single vanos cams in.

M54 cams will work fine, but I don't know how much you'll be gaining and if it's worth it.

is there an actual difference between the m54 manifold and the m52 manifold that i have? because if you look at the m52b25 (my motor) vs the m54b25 (01+ 2.5L) the m54 has 14 more hp but 6 less torque.

as for the cams 1000 bux is steep for a set of cams that one will go on the back burner till after the supercharger (which is also on the back burner)

[putyoursoxon]

why is the throttle body so low?? I think i'll just fog it hardcore

[2kredz3]

be better to take it off and clean it.

[putyoursoxon]

be better to take it off and clean it.

to much work, so low, i'll be losing nuts everywhere

[2kredz3]

You going to come to home coming?

If so remind me before hand sometime and ill bring some tools and we can do it in the parking lot.

[putyoursoxon]

You going to come to home coming?

If so remind me before hand sometime and ill bring some tools and we can do it in the parking lot.

I might, depends if school starts before it or not, I'm going to be the worlds oldest freshman, that what I get for joining the fucking navy

they definitely made it the most difficult throttle body to reach ever