E39 how to clean throttle body

Does anyone have a DIY link for cleaning the throttle body?

I have some advice for you.

Do not, I repeat, DO NOT! Manually move the throttle plate with your hands. Because it is a drive-by-wire, any movement you induce can permanently damage the throttle body. Ask me how I know.

heh i almost rather let it strand me now i have not problems YET but was told to look out for the throttle body getting too dirty , but seriously i may just have reputable bmw mechanics look at it and hold them responsible if anything thanks for the advice

I just replaced my Throttle Body due to a mysterious stalling issue. Codes were indicating Throttle Body problems. The replacement VDO Siemens unit was $245 for my 2003, 530.

My car had about 48K miles and the original throttle body was squeaky clean. I did however remove and clean my Idle Control Valve (ICV) with throttle body spray cleaner as preventative maintenance. ICV carbon build up was very minimal.

I think if you were determined to clean the Throttle Body, the safest bet would be to physically remove it from the intake manifold first. As PO540 stated, do not move the throttle plate manually.

It's a bit of a fussy job gaining access to these components (TB and ICV) on a 2003, so I wouldn't go poking around in there unless there was a specific issue to address. Just sayin'.

I just replaced mine as well. At 188,xxx miles it was due.

After researching and getting a new one from getbmwparts.com ($430) I learned from various I-net sources that mechanics don't even want to breath on these things if they've been in there b/c even partial drive by wire ('99 and '00) as well as true drive by wire ('01+) throttle bodies are prone to failing if you mess with it. (think: replacing your CCV and hoses and removing to clean ICV)

That said: I was getting monthly codes for the TB for a while (cleared and off we go) before mine totally crapped out.

Can DIY if you have ediabas / INPA to reset adaptions for new TB.

I just had my throtle body out and cleaned it while replacing the ccv. I think I moved it once or twice by hand. How bad is this? Also, should the valve be completly closed? My had a little gap when I took it out. Is that normal. Thanks.

Originally Posted by repcapale

I just had my throtle body out and cleaned it while replacing the ccv. I think I moved it once or twice by hand. How bad is this? Also, should the valve be completly closed? My had a little gap when I took it out. Is that normal. Thanks.

Little gap is normal (something like 1/16" to 1/8") in the closed position.

Perfect, thanks. So if the valve hasnt started acting up then it would be safe to say I didnt damage it?

Originally Posted by repcapale

Perfect, thanks. So if the valve hasnt started acting up then it would be safe to say I didnt damage it?

Most likely you didn't. If you did, your car would go into "engine fail-safe mode" and believe it or not it would give you a code on the information display area. It would show-up as a "throttle temporarily stuck" or the dreaded "throttle permanently stuck" message.

Good to know. I was worried for a second there. Thanks.

Originally Posted by POof540i

I have some advice for you.

Do not, I repeat, DO NOT! Manually move the throttle plate with your hands. Because it is a drive-by-wire, any movement you induce can permanently damage the throttle body. Ask me how I know.

Would this explain why my CEL came on about an hour after the cleaning????




540indiana reward for ignorance

I need to check my throttle body for vacuum leaks (pending P1085, P1083, P0171, & P0174), especially since my I6 died thrice going down a miles-long steep (thousands of feet) hill on the edge of Silicon Valley.

Bobdmac kindly suggested I check my throttle body for leaks; so I'm looking for a DIY that shows 'where' the throttle body is located.

Realoem shows a 'throttle housing assembly' but no locational information.

Is the throttle body just below the DISA (which is what this picture) intimates?

Originally Posted by bluebee

... stuff deleted ...

Is the throttle body just below the DISA (which is what this picture) intimates?

The arm's thumb is on the throttle body.
See Fundman's DIY for an M54 CCV replacment for tips on removal.

Regards
RDL

Originally Posted by rdl

The arm's thumb is on the throttle body ... See Fundman's DIY

Ah, perfect. I wasn't sure if what was in the picture 'was' the throttle body (because the picture came from google images with no writeup), or, if the throttle body was removed and that was something else he was pointing to.

Interestingly, I found the Fudman CCV DIY instantly using the /fudman(F3) in the bestlinks - and it was the very first hit - took about 1 second!
- Fudman CCV (aka PCV CVV) M54 replacement DIY

Reading that 8-hour job, I see how the removal steps work their way to the throttle body, so I can follow the arrows to the throttle body itself; but he has no pictures of the throttle body in situ. Looking at the car, I can see why. It's buried deeply in there! (No wonder we use the spray-can flamethrower-like accuracy method!)



Taking aim with the Brakleen & with carbeurator cleaner, I fired away. Again and again and again. Like a kid with a new double-barreled Nerf gun, I fired at everything I could with the two fluids. Maybe it was a hallucination but once or twice I 'thought' I heard an almost imperceptible change in engine speed firing at the vicinity of the throttle body, but only with the Brakleen (not with the California carb cleaner). If there was an engine speed change, it certainly was not dramatic.


Thinking ahead, I had cleared the codes before firing; lo and behold, the same four codes were pending for me, when I completed the half-hour test. Hmmmm.

Note: One thing we need is a picture of all the "aim" points, instead of this random firing at anything that moves trick.

BTW, additionally, I did the suction-of-the-oil cap trick, and it certainly had plenty of suction and dramatically changed the engine speed when I removed the oil filler cap. I forgot to test the dip stick suction (will do that later & report back).

(

BTW, additionally, I did the suction-of-the-oil cap trick, and it certainly had plenty of suction and dramatically changed the engine speed when I removed the oil filler cap. I forgot to test the dip stick suction (

What do these indicate?

Originally Posted by NY_98_528i

( What do these indicate?

Oil filler cap (or oil dipstick) suction is a measure of the operation of the CCV.

• Too much --> Bad CCV
• Too little --> Bad CCV
• Just right --> Good CCV

See this thread where we're debugging whether the CCV has a problem.
- Pictorial DIY for an M54 spark plug replacement on a 2002 BMW 525i E39 with 95K miles

I need to find a manometer to see if I have the right numbers.

Originally Posted by Fudman

You should have 3"-6" of vacuum pressure, as measured by a manometer, at the oil fill cap or the dipstick tube. However, this is not a foolproof means of determining CCV function.

- How to test CCV?

For the record, I opened a separate thread on the CCV today:
- How to test the BMW E39 pressure-controlled crankcase ventilation system (CCV)?

And, while researching the throttle body, I found another nice set of pics:
- Cold start issues and failed inspection

Here is a pic of the throttle body for a 2000 BMW 528i Sedan:

I just realized, when I did my alternator last August, I was tantalizingly close to seeing the throttle body in my own M54 engine!
- One users' example of total electrical failure (AAA towed away) alternator repair (1)

See this pic from post #93.

Hope this helps.

Regards
RDL

Originally Posted by rdl

Hope this helps

It does! Thanks.

Amazingly, even with half the stuff removed, they're 'still' buried in there!

BTW, I started a work-in-progress thread (in my secret hiding spot) showing a picture of all the hidden components in the M54 engine, one by one.

IT's not easy as I don't know where they are myself (e.g., the CMP, CKP, etc.), but, as they 'show up' in threads, I'll capture them, ad hoc, and over time, the thread will be 'ready' to publish.

Originally Posted by bluebee

...BTW, I started a work-in-progress thread (in my secret hiding spot) showing a picture of all the hidden components in the M54 engine, one by one.

Bluebee's Skunkworks project!

Originally Posted by bluebee

I need to check my throttle body for vacuum leaks (pending P1085, P1083, P0171, & P0174)

Long saga cut short ... as a belated update, more than a year after those first symptoms reported above, I only recently found the definitive source of my multiple lean mixture misfire codes alluded to above!

As Bobdmac had kindly suggested, I had air leaks in both the corrugated elbow to the idle control valve (ICV) and air leaks in the lower CCV vent hose to the dipstick guide tube which were causing numerous lean mixture misfire DTCs.

For the record, here is a picture of my M54 throttle body (and smaller ICV) from this more recent effort to unclog the oil dipstick guide tube CCV vent hose concentric connection:

Originally Posted by bluebee

Taking aim with the Brakleen & with carbeurator cleaner, I fired away. Again and again and again. Like a kid with a new double-barreled Nerf gun, I fired at everything I could with the two fluids... if there was an engine speed change, it certainly was not dramatic.

Personally, I think the oft-suggested carb cleaner misfire-diagnostic test is vastly less effective for lean condition misfires than a comprehensive smoke test for leaks.

Originally Posted by bluebee

additionally, I did the suction-of-the-oil cap trick, and it certainly had plenty of suction ... I forgot to test the dip stick suction (will do that later & report back).

A year after I said that, I actually ran the more comprehensive water manometer tests, which I recently described over here:
- How to test, clean, & redesign the original BMW dipstick guide tube (CCV vent clogs!)

Originally Posted by NY_98_528i

What do these indicate?

Originally Posted by bluebee

Oil filler cap (or oil dipstick) suction is a measure of the operation of the CCV.

• Too much --> Bad CCV
• Too little --> Bad CCV
• Just right --> Good CCV

Apparently I 'may' have a bad CCV because I have 8 inches of water column suction at the dipstick guide tube at cold idle, however, I have no other symptoms of a bad CCV (e.g., no exhaust smoke and no otherwise unexplained loss of oil) ... so I'm not so sure I do have a bad CCV just yet.

My 2003 car that I bought new, now has 230,000 miles on her. I have cleaned the throttlebody by removing the part and cleaning with throttlebody cleaner every 40k miles since she was new--along with the ICV. Now concerning moving the plate in the throttlebody--I have opened it all the way open and held it there very time I cleaned the part--have never had a problem with doing this--thats the way I have done the procedure and it's worked well for me--

Originally Posted by poolman

I have opened it all the way open and held it there very time I cleaned the part

Two things still confuse me about the throttle body cleaning and opening the plate.

1. Mine seemed clean as a whistle when I looked at the large and small opening. There was just a tiny amount of brown 'stuff'. I cleaned it with MAF cleaner in situ - but it really looked spiffy the way it was. I wonder why people need to clean it if all of them are this clean?

2. I moved slightly the plate (unknowingly) while the throttle body was attached to the engine and with the battery in place. I wonder if it makes a difference that you cleaned yours out of the car, where there were no energized electrical connections to worry about?

May , be just the fact tha I do unplug the part before cleaning it--but when cleaning with the part still on the car you only see the front side of the tb--there are carbon build up behind the throttleplate that need to be removed as well as the build up in front--thatswas a nice run on sentence wasn't it.