[bL79]

Ok just got a 2015 E84 X1 35i. N55 with PWG I'm pretty sure. ~117,000 mi

Installed the Evolution Racewerks CP and VRSF 7.5HD FMIC over the weekend.

Have the car on XHP (stg3) and MHD (stg 2) OTS tunes.

Filled up with some ethanol to make ~E30 today and try the Stage 2 MHD E30 maps. Also decided it was probably a good idea to look at logs finally. I did a quick before and after but realized I'm far short of boost targets.

What's curious to me is the WGDC doesn't seem to much exceed 50%. If I had a boost leak shouldnt I expect the WG and thus turbos to be commanded to near max?

After some reading and inspection I'm pretty suspicious of the boost solenoid vacuum system. I can pretty easily crush the fabric covered line with my fingers. Could that cause the issues seen? I can see the boost solenoid installed is Pierberg, were they OE or does that indicate it was replaced at some point?

https://datazap.me/u/bl79/x1?log=0&data=3-4-14-19

[wrevilo]

A lot of detail is over my knowledge, but I am certain the OE solenoid is Pierburg. I recently had mine replaced and used a Pierburg unit.

[bL79]

That's helpful, thanks.

Debating if I should R&R the solenoid and hoses or just the suspect fabric covered hose. The fabric wastegate hose routes over the exhaust manifold so seems like an insulated option is desirable.

Doesn't seem like that difficult a job but I'm not super looking forward to wresting the hose off the WG or solenoid nipples.

I guess sometimes when the solenoids fail they make a pretty obvious noise but I haven't noticed anything like that.

Hmm maybe Ill try to pull the line off the solenoid and vacuum test it with a mityvac

[swellengear]

Always a good idea to replace the old vacuum lines with the upgraded silicone options. It's cheap, and then at least you can rule that out.

Seeing as you installed a new charge pipe and intercooler, double check all your fittings. Hopefully something as simple as that!

[minulache]

You can test very easily the vacuum line that goes from the boost solenoid to the WG and also from the valve cover to the boost solenoid. All ypu need is a small vacuum pump like this: https://www.amazon.com/HTOMT-Automot...s%2C205&sr=8-5

If it holds vacuum, the lines are ok. Next step would be the boost solenoid. Unfortunately, there is no proper way that I found to test it, so maybe just changing it would be the deal. But before that, I would do a boost leak test so you have all the leaks tested and leave the solenoid at last. The testings are easy to do and straight forward, in tops 1 hour you can diagnose

[wheela]

In addition to making sure the vacuum lines hold vacuum, also check that none are collapsing shut under vacuum. I've seen some people post that they had no leaks, but the short vac line between the valve cover and solenoid was collapsing shut under vacuum. If vacuum can pinch it shut, you may not get sufficient vac to the wastegate canister to pull the gate closed strongly enough to make proper boost.

[bL79]

Thanks everyone,

I replaced the vacuum lines from the boost solenoid since I could do that quickly.

Took the car around the block a bit and seems the issue persists. Though I'm confident the lines were tired, I could easily pinch them and I swear it feels more responsive down low. Data does seem to indicate the wg moves a bit better now and I actually peaked at 70% which is new.

Problem persists though. I'm just going to order another boost solenoid since it seems old. Also just wiggling the brake booster vacuum line fitting causes a leak so I'll be replacing that too. Lastly Ill readjust the FMIC air entry clamp. I thought I tightened it well but visually it looks a bit suspect. Unfortunately that's the one piece of plastic still in the intake chain I fussed with so I was hesitant to go crazy tight on the clamps.

Latest log
https://datazap.me/u/bl79/log-172740...-24&zoom=21-70

[minulache]

Maybe it would be a good idea to also try with some other OTS maps from MHD, just to rule that out?
If after the boost solenoid the problem persists, I would do a boost leak test just to pinpoint exactly where the problem might be from. It's better than to just throw parts at the problem, but have no idea what it could be....

[bL79]

Yep, thats pretty much where I'm at.

Just retightened the T-IC charge pipe and flashed the stage 0 map. Stage 0 and Stage 2 logs below. Only issue is the stage 0 boost target is right around where the issue is so it's not as obvious how much boost is missing.

All the changes have seemed to help and I intend to make this car into a sleeper so I'm not too upset about replacing ancient vacuum lines and boost solenoids

stg 0
https://datazap.me/u/bl79/log-172745...-49&zoom=49-86

Stg 2 e30
https://datazap.me/u/bl79/log-172745...data=3-4-19-31

Also anyone know if the wgdc position target & wgdc % are supposed to effectively match each other when working or is there more involved?

[minulache]

Based on the amount of boost that you are losing, I am certain there is a big boost leak. Do that next and you will find out where the problem lies.

On my logs, my WGDC and position target are not matching

[wrevilo]

Sounds like a smoke test would help.

[bL79]

Anyone know an easy way to add smoke to a pressure test?

Been preoccupied with trans flush & mechatronics rebuild but got a pressure tester today and boost solenoid coming tmrw so Ill get back on the boost leak troubleshooting

[minulache]

At the turbo inlet plastic pipe, that’s where I did it. Anyways you will need to remove the same parts to get easy access to the boost solenoid so you can also boost leak test it.
Honestly, I have a smoke machine with which I did it, but you can find on Youtube various ways

[bL79]

Ok replaced the boost solenoid and it definitely helped a bit but still off target. It does feel noticeably stronger though.
https://datazap.me/u/bl79/log-172791...-19&zoom=50-90

Couldnt resist and just ordered a smoke tester. Unfortunately I couldnt pressure test today since the boot I got was the wrong size (should be ~3"). Also replaced coils and plugs for cylinders 1-4. Ill do 5&6 when I do the leak testing

[wheela]

Originally Posted by bL79

Ok replaced the boost solenoid and it definitely helped a bit but still off target. It does feel noticeably stronger though.
https://datazap.me/u/bl79/log-172791...-19&zoom=50-90

Couldnt resist and just ordered a smoke tester. Unfortunately I couldnt pressure test today since the boot I got was the wrong size (should be ~3"). Also replaced coils and plugs for cylinders 1-4. Ill do 5&6 when I do the leak testing

I haven't tried the e30 maps, but that boost is still really low. You do have stft going negative during the pull which could indicate a boost leak, but it could also mean e% is less than the target 30%. But since your boost is so bad, I'd lean towards checking for a boost leak.

I'm currently running ver. 1.6 stage 2+ 93oct with same 9e60b rom (X1 also for that matter!) so I'm more familiar with what to expect on that map.

[wheela]

Are you still on the stock downpipe? Stage 2 tunes are set up for being catless. If you still have the stock downpipe, that also may be a factor in the low boost. It would be intersting to see if your boost runs closer to target on a stage 1 tune.

[wheela]

It also may be easier to trouble shoot on a non-e mix tune, since if your mix is off it will affect your fuel trims. That makes it hard to know if trims are off due to fuel mix, or due to air leaks post MAF sensor.

[wheela]

Actually just looked at your stage 0 log, granted that was with your old boost solenoid, but that log was very low too - stock tune generally puts boost right on top of the boost request (and load actual on top of load request).

[bL79]

Good insight, thanks Wheela! Our cars are twins actually - 2015 Black X1 35i Msport

Car is still on the stock DP. I emailed MHD and they said the FMIC was more important than the DP and I should be good to run Stage 2. Though tbh this is my first turbo car and Im getting a little greedy with the idea of just turning up boost.

Interestingly it seems the latest stft and ltft adjustments are greater than they have been. I assumed the negative stft was due to the missing boost/load that the map is otherwise expecting.

Maybe I'll flash to stage 1 and just see what happens. Smoke tester should be coming today but Ill be gone tomorrow and this weekend.

[bL79]

Damn, did a smoke test and saw the IC-Turbo line was leaking a bit at the joint I suspected. I moved the clamp to the edge of the silicone hose and retightened. That seemed to pass smoke test but pressure test wouldnt get much past 5psi. Though both the compressor tank and test fitting were leaking so hard to draw conclusions.

The T-IC joint remains top suspect. Unfortunately after moving the clamp it seems I made things a bit worse from last time.

https://datazap.me/u/bl79/log-172843...-19&zoom=45-65

Maybe I'll look into cost and difficulty of a metallic outlet. The stock plastic one seems chintzy and it definitely compresses a good bit when clamped.

Edit: Though should note this is on a stage 1 tune and back on 91 ACN

[bL79]

Doing some more thinking as to why my WGDC is so low when Im so far off boost target and I'm wondering if the wg actuator could need to be adjusted? When just monitoring on MHD the car does seem to build a little boost when the target is 0. Maybe that boost creep indicates the wg needs adjustment? I guess that would explain why the WGDC is low with such a large boost leak

https://datazap.me/u/bl79/log-172852...=0&data=3-4-19

[montegoblu_e92]

Hi all, I'm new to turbo I6 Bimmer engines and I'm trying to learn more about tuning and how to read logs and diagnose tuning. All info is appreciated and yes I've read through the forum posts.

I just installed a 7 in. FMIC and flashed MHD v2.00beta Stage 2+ 93_oct (ran it for 2 days), and tested out the v2.00beta Stage 2+ e30 map today.

From stage 2 and higher my boost psi barely changes and actually went lower on e30 map.

From the logs I'm seeing of other e30 n55e owners I should hitting around 16-17 psi peak boost. My peak boost during a 3rd gear pull is only 12.8 psi at 15 psi boost target at 3500 rpm.

On stage 2+ 93_oct the highest I've logged is 14.9 boost psi which still seems unusually low.

Here's my e30 map 3rd gear pull
https://datazap.me/u/montegobluee92/...og=0&data=3-10

e30 map 1st-2nd-3rd
https://datazap.me/u/montegobluee92/...og=1&data=3-10

and 93 oct 1st-2nd
https://datazap.me/u/montegobluee92/...log=2&data=3-9

I just got the car in July @ 119k miles and I'm not sure if either of the fuel pumps have been replaced. Im suspecting it's on original fuel pumps and they're on their way out.

Any thoughts of why I'm not making boost? Or is the n55 pwg stock turbo just that bad? I plan to smoke test for boost leaks at some point as well.

Also how should I do logs? Full 3rd gear pulls only? Should I shift through gears at all? etc.