[aphael]

Hey guys, I just did my 3stage swap with brand new disas now I am running into a weird issue. The car starts up beautifully with the new starter, then dies right after. I cleaned the maf already with cleaner but have yet to flash the 330i tune. However the car will run without the maf plugged in, a bit sluggish but it wont die. If I give it gas it will stay alive but once I lift off it will die with the maf plugged in.

I havent plugged everything back such as that air quality sensor for HVAC. But I have everything needed pretty much plugged in. I did have some damage on the intake manifold but put a bit of rtv on the rough spots

Is this some kind of possible vacuum leak or am I missing something? I did not get any codes. and all hoses are pretty damn tight, i used a 6mm to tighten the clamps. I did not have this issue before.

[HydroxFrost]

I find starting right up and dying after is usually a sign of a completely bad MAF sensor, if you're not getting codes for your IAT at all I would honestly just try the nomaf tune. You could've possibly damaged it just by setting it down at a weird angle or touching the sensor part by mistake. Vacuum leak will usually run like garbage for a brief moment before it stalls out.

Edit: looked at this again and realized you said you didn't tune it yet. Try throwing on the tune and it might behave better with the new disas plugged in.

[aphael]

Originally Posted by HydroxFrost

I find starting right up and dying after is usually a sign of a completely bad MAF sensor, if you're not getting codes for your IAT at all I would honestly just try the nomaf tune. You could've possibly damaged it just by setting it down at a weird angle or touching the sensor part by mistake. Vacuum leak will usually run like garbage for a brief moment before it stalls out.

Edit: looked at this again and realized you said you didn't tune it yet. Try throwing on the tune and it might behave better with the new disas plugged in.

Come to think of it, I left the airbox sitting outside for a week as I waited for my disas to come, so maybe the maf is bad. I read that the car should be drivable with no tune. It made almost no difference after cleaning it. For the nomaf tune, would I need to add a iat sensor? or would I just leave the maf disconnected? I have only done this on other cars, not this bmw.

I have attached some videos:

maf connected, dies: https://drive.google.com/file/d/1HCW...ew?usp=sharing

maf disconnected, idle started fluttering after 20 secs:
https://drive.google.com/file/d/1HDu...ew?usp=sharing

[HydroxFrost]

Yea, if you left the airbox and maf outside there's a good chance its bad. That's the same thing mine does with a maf connected because my wiring is bad. Runs smooth without a maf though but its a 330 so its already tuned for DISA. With the nomaf tune you need an IAT but the maf sensor with the built in IAT will still work for the tune

[aphael]

Originally Posted by HydroxFrost

Yea, if you left the airbox and maf outside there's a good chance its bad. That's the same thing mine does with a maf connected because my wiring is bad. Runs smooth without a maf though but its a 330 so its already tuned for DISA. With the nomaf tune you need an IAT but the maf sensor with the built in IAT will still work for the tune

So I would leave the maf connected right, and just flash the nomaf tune from bimmerlabs?

[Marc81]

it's probably a large vacuum leak. check your ccv lines and vents. if they look good, smoke test it.

[aphael]

I drove it around and the throttle is the same after 25% kinda like I'm in limp home mode or something. I'm using the nomaf tune by bimmerlabs. Also weird is that the cruise control is working. There is almost no power

[HydroxFrost]

Originally Posted by aphael

I drove it around and the throttle is the same after 25% kinda like I'm in limp home mode or something. I'm using the nomaf tune by bimmerlabs. Also weird is that the cruise control is working. There is almost no power

Did you test to make sure the disa flaps actuated properly? A big vacuum leak will also cause those type of issues. I have a 330 so I've never actually done the 3 stage swap, but I'm assuming you got rid of the oil separator and ran the lines where they're supposed to go on the 328. Any check engine codes at all? If the maf was bad, and you left it plugged in and the IAT is also bad then it will definitely feel down on power.

[aphael]

Yes both disas were brand new from fcp euro and tested in inpa before installed. My intake manifold was a bit destroyed but I applied a bit of rtv to help seal it. Can the iat go bad if the maf is also bad? It will certainly drive and feel torquey in 1st and 2nd gear. But at highway speeds its slower than my miata

No check engine lights. Brand new pcv hose too, oil separator removed.

[HydroxFrost]

Originally Posted by aphael

Yes both disas were brand new from fcp euro and tested in inpa before installed. My intake manifold was a bit destroyed but I applied a bit of rtv to help seal it. Can the iat go bad if the maf is also bad? It will certainly drive and feel torquey in 1st and 2nd gear. But at highway speeds its slower than my miata

No check engine lights. Brand new pcv hose too, oil separator removed.

Try cleaning the IAT and see if that helps. It also depends where the manifold was damaged

[aphael]

Cleaned up the maf and iat, no difference. The nomaf tune is smooth but unresponsive when rev matching and low power. regular bimmerlabs tune is more responsive, slightly better power, but engine is rumbly and inconsistent at idle.

Going to check for vacuum leaks and tighten everything tomorrow. possible manifold leak but I havent gotten any error codes. Maybe add some more rtv to the intake gaskets since those did not seal well due to unfortunate wear of the plastic.

[Marc81]

Originally Posted by aphael

Cleaned up the maf and iat, no difference. The nomaf tune is smooth but unresponsive when rev matching and low power. regular bimmerlabs tune is more responsive, slightly better power, but engine is rumbly and inconsistent at idle.

Going to check for vacuum leaks and tighten everything tomorrow. possible manifold leak but I havent gotten any error codes. Maybe add some more rtv to the intake gaskets since those did not seal well due to unfortunate wear of the plastic.

use a can of starting fluid to check for leaks , make sure the engine is cold when spraying the fluid.

[nsjames]

Originally Posted by aphael

Cleaned up the maf and iat, no difference. The nomaf tune is smooth but unresponsive when rev matching and low power. regular bimmerlabs tune is more responsive, slightly better power, but engine is rumbly and inconsistent at idle.

Going to check for vacuum leaks and tighten everything tomorrow. possible manifold leak but I havent gotten any error codes. Maybe add some more rtv to the intake gaskets since those did not seal well due to unfortunate wear of the plastic.

where is the intake manifold damaged?

RTV on the intake side isn't really a great idea.
if it comes loose it gets sucked into the engine.

and don't tighten it passed it's specified torque. you used a torque wrench to install ir right?

[E92William]

We talked about his manifold on message. He should send a picture. It's almost as if you had gone on the inner part of the runners as they get to the mating surface to the head and shaved off the edge of the end of the runners around here. I have no idea how such damage could have even happened. Almost looks melted. Here's mine pointing to where for reference

[HydroxFrost]

Well if the leak is that bad, that's an entire cylinder not getting proper airflow. I don't know if there's any real way to fix it without replacing the intake manifold.

Originally Posted by E92William

We talked about his manifold on message. He should send a picture. It's almost as if you had gone on the inner part of the runners as they get to the mating surface to the head and shaved off the edge of the end of the runners around here. I have no idea how such damage could have even happened. Almost looks melted. Here's mine pointing to where for reference

[bluewater328]

Yeah, pics in the other thread sure look like some sort of fire or hack removal.

https://www.e90post.com/forums/showp...51&postcount=1

[HydroxFrost]

Ouch, it looks butchered across most of the mating surface. I'd be surprised if any of the cylinders are getting proper airflow without leaking.

Originally Posted by bluewater328

Yeah, pics in the other thread sure look like some sort of fire or hack removal.

https://www.e90post.com/forums/showp...51&postcount=1

[aphael]

Possibly will get a new manifold then. My original manifold looked normal when I took it out. Even the gaskets dont sit perfectly inside the holes.

[HydroxFrost]

Originally Posted by aphael

Possibly will get a new manifold then. My original manifold looked normal when I took it out. Even the gaskets dont sit perfectly inside the holes.

It has to be the manifold because you did everything else right and there's no codes, but its acting like it has a huge vacuum leak. I can't think of anything else.

[nsjames]

Originally Posted by bluewater328

Yeah, pics in the other thread sure look like some sort of fire or hack removal.

https://www.e90post.com/forums/showp...51&postcount=1

that looks like it came from a motor that got nuclear hot without coolant.


that manifold is trash.
You'll never get it to seal properly.

[aphael]

I just swapped back in my original manifold. Is there a set of instructions to go back to the stock 328i tune? I saw 5 stock tunes in the bimmerlabs downloads but dont want to be randomly flashing stuff. My acceleration doesnt feel too good at the moment at highway speeds. Feels like the throttle body isnt opening all the way when I floor it. 25% and 100% feel the same. My original manifold does not have any of these problems

[E92William]

My 328xi on the stock manifold and 330i tune was more lively and faster than stock so there's definitely some other underlying issue here.