Wastegate Duty Cycle Way Too High - Need a Wizard

oranjes

oranjes

Greenie N00B Member
Been tuning with Justin @ Freektune and he has recently given up in ideas on what's screwing with my boost pressure. He's had me change my wastegate spring from 17 PSI up to 21PSI but no dice. Other brains trusts I have consulted are also short on answers.

Engine mods are:
Damond PCV Plate
CS Intake & Exhaust Mani
CST5 IWG
Port Injection
100 cel cat
HDIGT2 w/ Mishimoto G-Line core
GFB BOV
3.5in HTP intake
on 98 octane (australian, think its 93 US)

As for most pertinent to possible intake issues, I have a bespoke catch can setup (in Damond's "bye bye blow-by" blog it's the last one they discuss), as well as a Cobb 3 Port EBCS and a Guardian Angel V3 and am using the GA's MAP sensor. All these have been tested, no leaks and all clean. May need to swap out my EBCS - could've gone bad, but doubtful. Everything I've changed between the WGDC being fine and it being a problem amounts to adding an airbox (which I removed just to simplify my issue hunting) and a boost, oil temp and oil pressure gauge (also removed boost gauge to simplify issues). I've had a couple tune revisions as well but I'm trusting that Justin knows what he's doing :p

The typical behaviour is that it hits 75% WGDC as soon as I WOT and creeps up to 95% by 5500RPM.

Please see attached logs. Log 91 is the last log before it started going haywire. Log 92 is when the issue really showed itself. Log 111 is where I am currently at. Changes between then and now are a smaller intercooler core, a boost leak fixed, and the wastegate spring being put up to 21PSI. The only other thing I can think of is when my car shorted out for a moment (uncertain if this was between log 91 and 92), in which I could hear my EBCS solenoid flicking on and off very rapidly. Electrical gremlins?

Cheers!
 

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for posterity the issue was my wastegate actuator was NOT tight enough

now i am having a seperate issue that is robbing the car for 30-50kw, aiming at 260 - 280 or so with CST5 at 26psi (no port injection yet) and only reaching 230-250. compression test is alright. boost leak test next. any other ideas let me know
 
Boost leak test for sure, which ebcs are you running? Corksports has been known to fail

280kw (375hp) at the wheels would be about the max for stock fueling on the ms3, now 230-250kw (308-335hp) does seem a little low.

That being said fresh plugs gapped to whatever freektune has advised (my guess is 0.026-.028"), clean MAF sensor.

@Easter Bunny @Enki thoughts? you two know more about fueling limits than I do
 
Boost leak test

What is the condition etc of the high flow cat? Possible it is breaking up and blocking exhaust flow
 
Swapped out the EBCS already from Cobb to CS as I was suspecting it for the wastegate issue previously. No difference at all between them

The plugs are fresh and gapped 500km ago, had them out for a compression test and still looked good. Compression was good across all 4 with one inconsistency, in that a wet test didn't increase compression in cylinder 4

Boost leak test didn't bring any enlightenment except telling me BOVs are always leaking a little but I will test again to make sure. Also tested the exhaust, and fairly satisfied it has no leak

If you think a blocked high flow cat has a good chance of dropping me that much power I'll definitely check it out

Will also clean the MAF
 
Should be fine, my car has had it for 500km and before that it was on another car for maybe a thousand. Will clean it anyhow
 
Awafrican said:
280kw (375hp) at the wheels would be about the max for stock fueling on the ms3, now 230-250kw (308-335hp) does seem a little low.

...clean MAF sensor
Click to expand...

mine is a MS6 just FYI

MAF sensor is cleaned

boost was tested twice and all good there

going to check the cat out soon
 
Cat looks good but there was a nut in it and the o2 sensor was sooty as hell. Will do a log and see if thats any difference.
 

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POWER

Year/Make/Model: 2006 Mazda 6 MPS/MazdaSpeed6
Mileage (km): 204,000 on car, 18,000 on built engine. 500 since engine install
Location: Australia
Concern: Missing between 30 to 50kw worth of power compared to very similar cars. Making 230-250 (depending on Vdyno setup) when I am told 260 to 280 or even 300 should be possible. I am wanting to sort this before moving into port injection.
DTC's: only on EGR and intake manifold flaps, for very normal and legal reasons

Modifications:
Built engine (forged rods and pistons, completely refurbished at time of building)
Xtreme twin plate 1200nm clutch
Damond PCV Plate and PCV setup according to most complicated setup in Damond's PCV blog
CS Intake & Exhaust Manifolds
CST5 IWG
CS FMIC
CS BOV
CS turbo and manifold blankets
Returnless port injection (not yet active but fuel to the HPFP is being ran through the port rail)
Split Second Controller
Guardian Angel V3 (using V3 for MAP sensor as well, spliced in with CS 3.5bar that came with the CST5)
100 cel catalytic converter
3.5in HTP intake
less relevant ones are suspension such as all 3 Damond engine mounts, rear diff mount, coilovers, big brakes, transfer case caps, rear sway bar
on 98 octane (Australian, which I think is 93 US)

ECU/Tuning Software: Cobb AP V3
Tuner: Freektune, AtenzaTuning
Is the concern intermittent?: Constant
Can you duplicate the concern?: Every datalog
Recent Repairs: wastegate arm was not tight enough so this was corrected
Attempted fixes thus far: ensuring crank position sensor is aligned, cleaning MAF, boost leak test, checked catalytic converter, checked compression
Correction: None yet

Thought I would post up in the proper format for posterity and keep it updated. Also see logs. Some are 3rd, some are 4th, some are idle.



 

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Threads merged, creating multiple about the same issue is not helpful.


Have you spoken to freektune about the issue? Might be the CS map sensor failing...wouldn't be the first. It could just be that you're engine doesn't want to do more....also you found a nut in your cat what?!
 
Awafrican said:
Threads merged, creating multiple about the same issue is not helpful.

Have you spoken to freektune about the issue? Might be the CS map sensor failing...wouldn't be the first. It could just be that you're engine doesn't want to do more....also you found a nut in your cat what?!
Click to expand...

Sorry, it's a different issue really which is why I did it, under a different title for more specific searches.

And yea the CS 3.5 did fail, which is why I'm using the GA V3 built in MAP wired to the harness which is otherwise connected to the CS. But I am worried - if the CS main signal failed, could it be sending other things wrong as well other than the wire that I spliced into? What are each of the wires to the MAP for?

As for the bolt yea, no idea Cant tell what its from, looks a little like an exhaust manifold locknut or even driveshaft maybe. Dont think it went through the engine.

Also have not spoken to Freek since fixing my wastegate. Don't want to waste any more of his time until everything is sorted - he was at his wits end trying to sort that out.
 
If your waste gate wasn't functioning that could be need a retune. Personally I'd swap that CS sensor for a Bosch one, I don't know the pin out on the sensor wires but yes if it's reading incorrect that'll send wrong to the guardian angle.
Are you still running a CS ebcs as well, it's fully functional? Those fail too, one guy went through 3 of them here before swapping to a different one and issue resolved.
You can make your own one pretty cheap
https://mazdaspeeds.org/index.php?threads/how-to-diy-an-ebcs.10919/
 
CS EBCS is functioning same as the one I pulled out to ensure the wastegate issue wasnt being caused by it, so fairly certain it's fine.

As for MAP sensors maybe I'll chuck the OEM in just to be sure. Think the GA interprets and sends everything based on the pressure going through it rather than anything on the stock location MAP, but there are like 3 more wires to the stock location MAP so I dont know.

Also want to clarify, I am hitting boost targets perfectly as far as I can tell. Look at the logs, near instant 20psi spool. Just low on power. It has been retuned since the wastegate issue too.
 
Just to see if I can field any more ideas I'm gonna update this thread with what I tried and checked and what I'm starting to think it could be. Changed the CST5 to an EWG and fixed a fairly major exhaust manifold leak as well as a BOV that was always opening.

Currently retuning but getting to a similar stage as I was with IWG and its still fucked.

A while back I did a leakdown as well. It showed 30% which was worrying but I was thinking 1. I probably messed up the leakdown test somehow, and it was done cold and 2. the boost being added should be doing a bit more regardless. If I'm wrong and this is very silly and my motor needs major attention that would be good (horrible) to hear. I just bought an oil diagnosis kit to see what sort of wear is happening for some sort of confirmation before I grapple with the idea of getting a rebuild.

I've heard CS throttle bodies can have silly horrible problems that make people chase their tail and mine has had a CS TB the whole time too.

Thinking of checking my timing but the engine is only maybe 25k Km old now. If I check I will update this again

Maybe fuel delivery issues from an injector? I have no reason to believe this, I just don't know exactly how the guy who rebuilt the engine sorts his injectors

Could my PCV system be causing issues? Its pretty complicated and I can imagine it going wrong in a few ways, like if a check valve was jammed or just generally if it's not sucking well enough
 
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DO NOT DO ANOTHER WOT PULL.

Things that are fine:
  • AFR
  • Boost
  • Load
  • Rail Pressure
  • Intake/boost temps
  • KR
  • Overall airflow
  • VVT
  • Ignition timing (if running pump gas)

Things that are NOT fine:
  • IDCs (>100 is not ideal, >120 is worrying, you are closing in on 140)
  • STFT (>20%; you should be seeing a CEL for this soon if not already)
  • WGDC (You have no PI going on, so it should be reducing boost to fit within DI window; instead it's increasing to meet target)

If you had more timing in this tune, it would be misfiring due to ignition hitting while still spraying fuel. I don't think I need to tell you how bad of a problem this could turn out to be.

It's time to discuss with your tuner.
 
Enki said:
DO NOT DO ANOTHER WOT PULL.

Things that are fine:
  • AFR
  • Boost
  • Load
  • Rail Pressure
  • Intake/boost temps
  • KR
  • Overall airflow
  • VVT
  • Ignition timing (if running pump gas)

Things that are NOT fine:
  • IDCs (>100 is not ideal, >120 is worrying, you are closing in on 140)
  • STFT (>20%; you should be seeing a CEL for this soon if not already)
  • WGDC (You have no PI going on, so it should be reducing boost to fit within DI window; instead it's increasing to meet target)

If you had more timing in this tune, it would be misfiring due to ignition hitting while still spraying fuel. I don't think I need to tell you how bad of a problem this could turn out to be.

It's time to discuss with your tuner.
Click to expand...

I did probably another 20 WOT pulls after the logs you'd be looking at...

But anyway the issue is in terms of power not being made as boost increases plus the wastegate duty cycle being way up there. This has remained the same even with another tuner. Take a look here:

6 and 7 are on same tune revision, 8 and 9 are another revision
 

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Last time I saw a car with a fat chunk of lost power at good airflow/fuel/spark levels, it was my car and due to inadequate crankcase breathing. Cost me 40 WHP.

Still, you shouldn't be running WOT pulls in bulk like that with such a high IDC.
 
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