Tuned car pulsating between 3000 and 4000 rpm

[kiysersosae]

Been having some strange pulsating when wot from approx 3000 rpm to 400bhp then it clears, I went back to the stock file and the car is fine.

I had just loaded a file (not piggy back) wich is aimed at 400bhp. I done 4 runs 2 of which were when the iat was reading 45deg c and 2 runs when iat was reading 51/54 degree c. The 2 runs that were done in 3rd gear at 45deg c were fine but the 2 that were done at 51+deg c were heavily pulsating.

Car Spec

DeCatDp
Full supersprint exhaust no cats
Afe air intake
Fmic

Any Ideas?

Car Never done this on stage 3 tune but I cant reload that.

[lowbudgethero]

tc was fully off?

[kiysersosae]

Originally Posted by lowbudgethero

tc was fully off?

Mdm mode

Does not feel like tc interference its' something else?

Was bosting 17.5 and smelt like running rich atat standstill

[lowbudgethero]

I get pulsing when I have TC on, even with mdm mode you might get some reduction in power. However, based on what you said it seems like it could be the tune itself, the timing or afr might be too aggressive. You'll have to do a data log to be sure of what's going on.

[kiysersosae]

OK cool.

I can't data log with my tune.

I've raised the issue with the tune developers and they are helping with the issue.

It's strange that after the new BMW software upgrade I had done just before I sent the stock file away for tune it's started. It was fine with the heavier tune so I'm as you are and leaning towards a mistake on the tune file.

Hopefully I will get some more answers tomorrow. I'm en route to nurburgring and would like the tune file sorted if that's the issue.

[kiysersosae]

No answers as yet on the pulsating from tuning company so I've just completely removed the tune. Car is booked into BMW on Wednesday next week to have it checked over. I've asked them to check; injectors, coils, fuel pumps, spark plugs. I don't think it will be anything to do with any of this as it runs great on stock tune but I just want to make sure.

Also, when I removed the tune and reflashed to stock Ecu, it showed that my oil was in need of immediate change (red triangle) as of the 01/2001, so I don't know what happened but il need this reset too.

[Smiley1175]

Would this be an Evolve tune?

[MDORPHN]

Sounds like a tune, not a hardware (plugs, coils, etc.) issue.

When running an aftermarket tune -- especially at higher boost levels, logging capability is essential. Just my two cents!

Neil

[Dackelone]

Sounds like a lean surge. Sure your A/F ratios are right?

First thing I would do is spark plugs and see IF that changes anything.

[kiysersosae]

Originally Posted by Dackelone

Sounds like a lean surge. Sure your A/F ratios are right?

First thing I would do is spark plugs and see IF that changes anything.

The spark plugs were new 4000miles ago but I've asked for them to be checked when it goes in. Be interesting to see what Bmw have to say.

Not sure on my a/f values as I don't have the ability to monitor. If they are wrong would that be tune or maybe sensor fouling? I've stuck some fuel cleaner in and I've just about finished the tank with it in, don't think it will be this but I've tried.

Would my code reader find all codes or are there hidden codes that only they can see? I have a code that appears all the time 2fa3 even once flashed back to stock but I think this is a BMW code that shows they system has been tampered.

Smiley 1175. Don't really want to say who it is as it me be a fault with the car so il leave it for now.

[Dackelone]

Originally Posted by kiysersosae

The spark plugs were new 4000miles ago but I've asked for them to be checked when it goes in. Be interesting to see what Bmw have to say.

Not sure on my a/f values as I don't have the ability to monitor. If they are wrong would that be tune or maybe sensor fouling? I've stuck some fuel cleaner in and I've just about finished the tank with it in, don't think it will be this but I've tried.

Would my code reader find all codes or are there hidden codes that only they can see? I have a code that appears all the time 2fa3 even once flashed back to stock but I think this is a BMW code that shows they system has been tampered.

Smiley 1175. Don't really want to say who it is as it me be a fault with the car so il leave it for now.

Just a though... but maybe your dealer used the wrong plugs. Its quite common for N55 plugs to be used instead. It WILL make the car run different.

Or... they could have dropped one plug. I think I would tell them to install SIX new spark plugs and retest the car.

See post #5 bellow...
http://www.e90post.com/forums/showthread.php?t=574328

that's odd you're getting that code....the 2FA3 code is the one that shows up when you have the Cobb Accessport installed. it has something to do with an unknown software running on the DME.

It looks like your ROM file is corrupted and you need to flash back to your stock map/file. I hope you saved it. ?

http://www.german**********/showthre...-still-present

Otherwise you will need to have a dealer(ie you will need to pay) to have a SW update done. This normally only costs one to two labor rate hours.

Good Luck,
Dackel

[kiysersosae]

Thanks for the feedback all.

Il get the sparks checked and il get the software reset by the dealer.

I would have thought if the spark plugs were bad it would be in all gears all the time even on stock file not just Tuned file?

I've been looking at the ac schnitzer piggy back ecu and been offered a really good deal on this so I il get the ecu flashed, leave it and just run the piggy back ecu from ac, it arrives next week and I have 30 day money back guarantee. Any comments on this system? I know it adjusts the injection pulse width amongst other things but it will be interesting to see how this works as they claim 400bhp with is the same as the software flash tune was so it will be good to run stock ecu software and see if the pulsating is there. That is of course unless bmw find the issue before then.

[kiysersosae]

Ok an update to this post and a possible solution.

I took the car to new BMW dealership and asked for an ECU re-flash and to check for any issues regarding the information above. The car was in all day and when i went to get the car i got handed a list that stated: modified cats, BOV, non-BMW air intake and Corrupt ECU. I asked them, so what have you done and they replied that they had done nothing and would do no fault finding as the car is not Stock, they also said that they cannot re-flash the ECU because they don’t have the software to do this and because they are locked out, yet they produced historical faults etc and told me about the cat codes that were showing. I spoke to the manager and he said he cannot re-flash the ECU and he thinks i have a tune. It was on full Stock file so he is talking bull Sh*t. They tried to charge me £150 but the service guy (not manager) let me off with the lot!
Anyways, il take the car to my normal garage where i have never had any issues with it in the past and have them sort out the ECU.

When i go the car home i decided to take the covers off the engine, strip charge pipe etc and give everything a really good clean -as there was allot of oil below my inlet manifold - after my 2500 mile euro trip. When i removed the Charge pipe i was shocked with the damage i seen. Il post this in a new post link to follow. The charge pipe, at the flanged end, was internally badly damaged and the BOV weld was in terrible condition with bits of weld flaking off, il investigate the cylinders with a boroscope next week. So, i think this may be the cause of this pulsating at high boost pressure, possible air leak. Il test the new charge pipe when it arrives but in the mean time il fit a custom rescue gasket and file down the weld.

[davemawshall]

Is this the type of issue you're having?

https://youtu.be/UG82UYvzAr4

Not my car however sounds exactly the same

I've had 6 new spark plugs put in, 21,000km on car only

No fault codes showing

Car has mc-chipdkr tune...

It's really annoying!

[kiysersosae]

Yes that's it, what's your car setup? Is it the same with tune removed? What bhp and boost are you running
I've got mine down to it was either the tune or the charge pipe. I've carried out a temporary repair to the charge pipe and added an updates tune and so far no more issues. I also cleaned the sensor on charge pipe.

[Tinsta]

How many miles does it have? has it ever had any walnut blasting?

[Snertz]

What tune are you running, Cobb OTS? If so, recommend getting Cobb ATR and dialing down WGDC base and WGDC D-Factor. Same thing can be done if you're running MHD or one of the other free flashing methods, use Tunerpro to make the changes.

It sounds like the car is exceeding requested load due to boost overshoots caused by excessive WGDC. PID is fighting it back down hence the oscillations, until actual load falls below requested load.

I had the same issue on my car, found that scaling D-factor down by 20% and dialing down WGDC base in the 2.4 factor row for loads above 130 smoothed things out significantly.

Since you mentioned damage to the charge pipe, underboosting may be causing the same issue. PID will try to dial in WGDC to raise actual boost, causing that same oscillation feeling.

[davemawshall]

This is the tune on my car

http://mcchip-dkr.com/chiptuning/pkw_bmw_1er_e87_m-coupe-stufe-1_340ps

Car has

Milltek catback
Bms dci intake
The tune as above
KW v3 coilovers
21,000km
Just serviced, new spark plugs installed by bmw


Maybe step one I should check the charge pipe for cracks etc and clean the sensor

Step two take it back to the tuner???

Originally Posted by kiysersosae

Yes that's it, what's your car setup? Is it the same with tune removed? What bhp and boost are you running
I've got mine down to it was either the tune or the charge pipe. I've carried out a temporary repair to the charge pipe and added an updates tune and so far no more issues. I also cleaned the sensor on charge pipe.

[kiysersosae]

Did you solve this?

[Xaeryan]

Originally Posted by davidmc21

Is this the type of issue you're having?

Not my car however sounds exactly the same

Whoa, my car also sounds exactly the same!

In my case, I think Snertz is right about it being the PID for the wastegates. Problem is, the reason it can't dial in correctly is due to wastegates not working well at higher boost pressures (maybe sticking? Maybe too tight?). Since it wasn't always like that, I suspect some replacement WGs would correct it. They are extremely expensive though, but they do come with a free turbo at least.
If I play around with the vacuum solenoid setup, I can reduce the surging greatly.

[davemawshall]

I get the feeling it only does it when the Overboost function kicks in (as it happens for a few seconds then smooths out) - so your WG idea might be right?? Seems to be when the boost hits max PSI and the car doesn't like it.

My car is tuned so I am going to see if it's a tuning issue but I am not convinced it is.

I've been thinking maybe the stock DV's aren't holding the extra boost - have also considered perhaps IAT are an issue - so I've ordered an aftermarket intercooler which should arrive soon... if the intercooler does nothing I will try a CP with aftermarket DV's... then back to the tuner if that doesn't help!


Can you PLEASE explain what you mean by "Play around with the vacuum solenoid setup"? I'd really love to be able to reduce this surging somehow... It's starting to really bug me

Thanks!

Originally Posted by Xaeryan

Whoa, my car also sounds exactly the same!

In my case, I think Snertz is right about it being the PID for the wastegates. Problem is, the reason it can't dial in correctly is due to wastegates not working well at higher boost pressures (maybe sticking? Maybe too tight?). Since it wasn't always like that, I suspect some replacement WGs would correct it. They are extremely expensive though, but they do come with a free turbo at least.
If I play around with the vacuum solenoid setup, I can reduce the surging greatly.

[E30 Racer]

As others have stated, I'd look at your WGDC during a full throttle pull from 2k RPM. Sounds (literally) like your PID settings need some tweaking.