I soda blasted my valves, only 20k after the last time I've done it and the coke build up was still too terrible to let go. Then I installed RX Speedworks OCC hoping to never have to soda blast my valves again cause, you know, that would be nice...

When I start my cooper everything seems fine for about 30-45 seconds but then the throttle climbs up slowly and then drops, and again from 1250 to 1000, relatively quickly like someone tapping on the gas impatiently at a red light, but it won't stop. I can rev the engine when I first start the car, but once this starts happening I can floor it and it won't do more than 3k. I can limp it around but I'd rather not.

 

Sounds like you may have created a vacuum leak. Retrace all your steps and connections.

 

I was thinking something along the same lines but I've traced and retraced everything, zip tied connections that are tight to pull off to reduce variables. I've also discovered I have an exhaust leak which doesn't make detecting anything by sound easy. I'm heading back to the shop now, thinking I may upload a video and post it.

 

I have a little clear tube that connects the the top of my OCC to the bottom for a visual indicator of oil accumulation. Mine was leaking at that spot.

 

Check MAF and cam sensor connections for full snap on. Try resetting the ecu if necessary disconnect the battery. There is a reading for adaptable ECU function on one of my ECU tools. It could possibly clear after a few starts. be sure the MAF didnt get any oil on it. The inlet pipe can be a bit of a mess at times. remember the turbo seals can also be a source of oil in the intake so check at the intercooler afte a bit and clean the whole intake track. have you looked at the exhaust side they can get cruded up too. And check that no crud is on the valve seat if necessary crank engine by hand and do compression check. Check for vacuum on the crank case, at idle remove oil cap cover with your hand you should feel slight pull or at least no pressure pushing back depending on blow-by rev a bit to 1500rpm. Check ECU for firing misses.

 

Back at the shop, couple more observations.

From first start up to the beginning of the throttle going up and down there is (was, since I pulled out the camera I can't reproduce the sound) a distinct change, there is suddenly what can only be described as a Darth Vader sound, you know the one, and to the ear it seems the sound is coming from the air filter, obviously it isn't but some valve somewhere is releasing pressure and Then the problems start.

Unplugging the battery seems to have zero affect. I've tried searching for a vacuum leak both with carb cleaner and propane, everything seems air tight. Going to let it cool for a bit and try to recreate Darth Vader sound on camera.

Also, after Darth Vader strikes I have very slow pedal response and no boost, but before hand everything seems fine... Damn you Darth Vader

 

Have you ever changed the valve cover, there is a vacuum regulator with rubber seals that can go bad, it usually causes a code to pop up and can set the ECU to limp. It might cause a leak to the outside. but its not usually so noisy. Try the compression check.

 

What if I've got a lot of air coming out of the valve cover from the oil cap? Like.. A lot. Like, the same as if I was holding my hand near the exhaust....

 

It is a mess under the intake manifold its quite possible to cross up something or not get a good connection like vacuum to the turbo regulator or something... could one of the oring seals get twisted on the manifold and be hard to get even propane to change things up

 

ok if the engine was running ok before then it could be a blockage and not a leak... so no blow by is getting out of the crank case maybe, so be careful, if the pressure builds up it will probably blow some seal at the valve cover or elsewhere check for oil leaks later. Worst case is piston ring seal but dont worry about that yet

 

So I've set my system up just like this, I have my check valves flowing away from the catch can, I have the breather on the driver side of the valve cover like in this video but here's where I go from baffled to pissed. I start huffing and puffing whereever I can to figure out wtf and there's a check valve in the valve cover on the drivers side that only allows air out and not in.. So the device meant to allow clean air to enter the crank case is literally doing nothing.. And it's not like I can replace the oil cap like it's meant to because the adapter is just completely wrong.

So now I'm not sure what to do, nothing I've tried seems to work, I really don't want to return to factory configuration because **** soda blasting the valves every so often... I love my mini Cooper but damn it's like they don't want us to keep these cars

 

Can you post a diagram? They did seem to have this working. A good catch system does help a lot, but remember the crank spins and makes a mist of super fine oil Ive even made filters to help catch this but the very last bit is hard and with the huge volume of air moved over time some oil will pool in places and make its way along. (not trying to be discouraging I think catch cans are a must)

Ive taken apart and cut up valve covers the rubber material does degrade and might cause trouble for this set up, its a bit hard to test. the inside of the covers passages can also get crudded up. Ive just changed the covers but for this I would try and confirm first.

Ill try and check back later if you want drop me pm

 

Now I'm truly baffled. Just to verify the problem isn't the catch can I completely removed it and returned everything to as factory as possible and the problem persists. I guess to some degree this helps but now I get to remove the intake manifold at least the 4th time in two days. I'm getting very, very over this project. For something I expected to be easy and simple this has become everything but

 

I think I finally found the source of the problem, took me longer to find a part name though, there's a funky shaped box that is called a vacuum take and a small electrical device called the pressure converter (presumably converts mechanical pressure to digital output) and some lines between the two. There seemed to be a very loose fit between one of the cables and the vacuum tank, I'm gonna proceed with the ****ery and see if I can't yield results

 

Did you fixed your problem? is it the pressure converter the problem?
I am about to jump in this project soon.

 

I did not fix it, unfortunately. It does seem to be related to the pressure converter because when I release the vacuum from the vacuum tank with the engine not running (I'm not sure if it's supposed to retain vacuum like that or not) then when I restart I get the minute or so of everything seeming like a perfectly normal start up before it goes back to rpm hunting mode, whereas if I just kill it and start it back up it goes almost immediately to rpm hunting mode. The bane of my existence certainly seems to be whatever the source of the darth vader noise is. It's very momentary but I managed to catch it at the end of this clip although you may need to turn up your volume to hear it.


For a little bit I had thought maybe I had mixed up the wire plug ins from the pressure converter and vacuum solenoid but it seems like the wire for the solenoid is too short to possibly mix up. Every time I think I've got the problem beat I just get stumped again.

I don't have diagrams but here are some snap shots from video I took. The check valves flow away from OCC, the dirty line directly to OCC is not valved (although I know now the valve cover has at least two internal check valves). Not sure if dropbox will work like this so I may need a moment to upload elsewhere...

https://www.dropbox.com/s/h14my9acea...09246.jpg?dl=0

https://www.dropbox.com/s/spffvv7zbk...12000.jpg?dl=0

 

What codes are coming up. If the catch can is out and the problem persists I would solve that first then get back to the catch can, no fun being down a car. It would be good to be sure of the throttle position, fuel pressure, timing vanos etc. Even with pics and the engine out It can be a pain under the manifold they sort of just made a mess. I have used the wire diagram and pin outs from the ECU to confirm things when completely lost.

Not sure which step to take next but if you are pretty sure of how the under manifold mess is connected. then try the following:

to check the valve cover try disconnecting all the hoses, plug the manifold and turbo intake, plug the valve cover rear outlet, be sure the driver side cover hose is open and start with the oil cap off then put it on, the blow by should make its way out the drivers side hose, see how the car runs.

The engine sounds pretty nice so I would think a glitch

 

I know those connections one to the turbo solenoid... I cant remember how the factory routed them, but there is the support for the bottom of the manifold and Ive gotten the routing warped around the wrong side of the support. it is possible to change those connections the way I end up routing things. I think the other connection goes to the gas tank purge system.

 

WrenchMonkey, you need to find out which code the car is throwing, that way you can have a start up point.

 

So I've found a thread of someone who had a similar issue and they resorted to replacing the solenoid and the converter but the problem ended up being the vacuum lines themselves which seems like that may be my case as well, the vacuum lines that connect to the vacuum tank have very soft rubber connectors with hard line in between. Apparently under vacuum that soft rubber can collapse, effectively closing that line in places it was never meant to close.

So I'm running to the autostore on my way back to the car, buying some kind of rubber line, vacuum, fuel, radiator or whatever has the right inner diameter and resistant to heat and collapse.

I'm also going to see if they have an OBD2 scanner I can burrow/ rent and if not I may be bothered to buy one. I know schwaben just came out with a new one and I'd been interested in one anyways to reset my damnable airbag alarm from when I removed the seats.

 

Update so I found a scan tool and the codes that I've come up with so far are p1638, p1637, p2103, p1631, p1497, p1600, P3901, C0121.

Most of these don't appear to show up in the Mini Cooper Library of OBD II codes and faults list which is irritating so searching the entirety of several different forums including LS1 Chevy trucks Chevy aveo's Toyota civics and various other forums I have found that some of the codes are related to the throttle valve position possibly being stuck open one is a generator L terminal circuit which I believe is probably from when I disconnected the battery to try to reset the ECU throttle control relay short which I'm not entirely certain what I'm going to do about that if there's anything I can do about that then apparently one of them is false anti-theft password Highway V what I got from the internet which is you know oh so reliable Downstream throttle air leak I'm sure that's probably from having the engine running with multiple different connections and hoses being disconnected at different points trying to find out what problems were p1600 seems to be something about the battery what you get I'm not worried about p3901 and c0121 I haven't been able to find anything for so that's cool. I'm going to stop doing the Google thing of all the codes and try to replace the extremely soft vacuum hoses with some slightly stiffer stuff and I will find out if that works and since I will have the intake off again I'll inspect the throttle valve

 

Unfortunately that doesnt seem to have been the problem. Im at a total loss, I can't point to anything directly that's causing this issue. I really hate having anyone else work on my car, even worse is paying them to do it but after doing something that was supposed to be fairly simple now my mini is pretty much down for the count. Damn

 

Pulled the plugs and ran compression test just for funnies and not too surprisingly the pressure per cylinder went up after the soda blasting in all but one cylinder (which had the best pressure of them all anyways, lol).

Here's a question for those of you more electronically inclined, the throttle position sensor was reading 18 on the scangauge2 no matter what I was doing with the pedal.. According to some of the codes it seems like my "throttle body" (I'm sure there's a different name for it because bmw is special but come on, it's a big butterfly valve right in front of the intake manifold..) really did crap out on me at an inconvenient time. Some one please give me some guidance/ share your thoughts, I would really love to find a solution to this problem besides using the "just buy and replace everything it could be until there isn't a problem" method.

For the curious my 08 r56s has 105k miles, was soda blasted just 15k miles ago, the pressure per cylinder from passenger side to driver before soda blasting was 130, 132.5, 139 and 150. The psi after soda blasting is 137.5,135, 145 and 150. I'm not a math guy but measurable results make me happy. Now if only I could get it running properly

 

Hi Direct injection, electronic throttles work very differently than port injection. at start it should be open and only closes when under hard acceleration. DI is more like a diesel the injector rate and timing greatly effect the charge, throttle position is kind of a support control. So that may be ok but the electronics constantly check position. With so many codes it seems like the ECU is hitting panic mode trying to make sense of what its reading. Its been a while since Ive gone by codes I usually log stuff. Im going to just quick guess but the O2 sensor and the expected reading are probably way off. That suggests the Valve cover is supplying a major leak or the MAF got fouled. If I remember right P1638 is what came up on a bad cover for me its been awhile. I have to fix a loose step so will check back later if I can did you try the valve cover bypass? If you could borrow an MAF to check... any R56's near by.

 

It doesn't seem likely to me that it would be the maf just because it's been encased the whole time, when I remove the top half of the intake I pretty much pull it out as one assembly. If the throttle body is normally open during operation why then is it's default when not operational is closed? Seems bass ackwards but I'm a logical person and clearly logic is not what these cars were engineered around.

I've called the local junkyards to no avail and unfortunately although r56s are common in my area it seems enthusiasts are not. The nearest mini dealer is quite a hike from me, especially limited to 30 in third gear.. So I'll be making a trip to the BMW dealership tomorrow. Providing that the weather in my area doesn't go as fubar as this project has, which is apparently quite possible according to the weather men.