Boost, Stumbling, No Power
 

One issue fixed, another surfaced. :crx:

What is happening is once i get into boost, especially WOT, the car just stumbles as RPMs climb and has no real power.
My N.A NA6 actually feels faster than my Turbo. :vash:

I thought it could be Ignition based so I put colder range plugs, BKR7E in and Gapped them down to 0.030" but the issue is still there.

Could someone kindly look at my 3rd gear short pull LOG to see if it tells the story better than me?
One thing i noticed was the RPM in the log gets very SAWTOOTHED in boost. is that normal??
I would appreciate any help!!

http://www.mediafire.com/?727qe7go2y4xwmg


Thanks in advance.

What's your afr gauge saying? Can't see log on phone.

Its a very short run, but they sit at 12.3/12.2 quite solid.

What's your setup? Age of plug wires?

Td04
Intercooler
1.6
MS2 Brainy
NGK Blue leads bit over a year old, can try another set.
8PSI
New Plugs
Original Coilpack and Ignitor

What wideband is it, and does it have a display on the wideband controller to verify AFR that is datalog is correct?
Also 16 degrees of spark timing in that area correct?

.030 is still a fair amount of gap. Recommended is a bit tighter (.020-.025).

Have you listened with a det can?

I had issues with spark plug gaps at .045 so I gapped them to .034
stock 1.6 ignition
This was at and above 1 bar of boost (14.5psi) on a t3 60 trim. My rpms weren't doing the weeble wooble like that though.

What is your overboost protection set to?

I had a look at the log - it's not overboost protection. Strange thing is I can't find anything other obvious in the log... AFR's do look good (did you recheck them on the WB gauge?)

Did you set the base timing correct?

the ignition isn't still locked after the initial sync is it?

Ignadvance in the log shows reasonable values...

k

Sorry for the lack of reply.
Damn Earth being dark on my side :)

Ignition is set to 10', verified with Timing Light.
Haven't used det cans.
The car starts to boost fine then becomes bogged and starts "vrrrm bat bat vrrrrmmmm bat vrrrrrmm" for lack of a better description.
As if spark stops.
When i was using the standard plugs i did not notice this but it was not as cold as now and Brain said i had too much timing to be safe ... oops.

If i use half throttle it feels better.

Wideband is LC1.
I have a innovate g5 gauge and it reads 1/4 point different but looks solid.
Checked the plugs and they look a bit rich.

datalog with part throttle in boost and full throttle in boost?
also tune file

Sounds like a bad coil.

Another thing that hit me over night is i noticed at idle a 'misfire'.
Every second or 2 it would sound as though it missed a spark event.
I did not notice this before and i think i put it down to my idle not being fine tuned yet but maybe it is the same issue under boost @ WOT.

I think i have another coilpack floating around and different leads so i guess i will go give that a crack.
I will also bring the spark gap down to 0.025.

Thanks for everyone's advice so far.
Much Appreciated!!

so i changed coilpack, regapped plugs to 0.025 and newleads.
Issue still there but perhaps slightly less.

But still weird power loss issues.
Thought about it and i am pretty sure it started after i made a cheap intake with a JustCrap silicone 130' hose.
I had a look and it is so soft, it just collapses with slight pressure.

My question is :
Under load/boost would there be enough vacuum to suck this closed??
Or is that a dumb thought??


http://www.youtube.com/watch?v=3YJMb...ature=youtu.be

Here is a vid of how easily it collapses.
I am using almost no pressure.

.25 seems awful close. I'd try .30 or at least .28 for a start.
My initial reaction leads to secondary ign. That's the least reliable part of the system. Usually.
Are you using 'normal' plugs? Or something 'exotic'?
Also, if your 'intake' was collapsing, wouldn't your O2 show this? (rich?)
A Loss of power could be a lean condition. Intake leak maybe?

BTW, This post is influenced by no slight amount of inebriation, So,take it with that in mind..
.

Its the pipe.

Dann

Can't see your vid. If the intake you're talking about is on the suction side of the compressor, then your theory is plausible. Can you swap it out and test?

It is on the suction side.
Straight off the compressor, 130' then straight pipe to filter.

I will try and figure out a way to lose the silicone.

Wish i had off thought of this a week or so ago..... UGHH!!

Will report back results..

Might take plug gap back to 0.030 also.

Yeah, run the biggest gap you can without engine miss.

Dwell dude

??????

hah I'm lost :noob:

You CAN put something in the pipe.... like a pvc section to stop it sucking closed, but it MUST NOT be able to fit into the compressor, ive seen a brand new GT35 killed this way.

Dann

Fae means ignition dwell. If it's not set correctly, you'll have a weak spark.

However, your approach is better. 9 times out of 10, it's messing up because you messed it up, not because something randomly failed. So, think back to when it was running right and try to remember what you did (wrong).

Wow that is super fails!!!


Dude just replace the flex fail section with hard pvc pipe. For the intake, it is legit.

update..

Lost the silicone joiner but still had stumbling and No power.
Whacked a 2.5" Exhaust with a new Cat on and issue was still there.
For shits and giggles we added some more fuel to the REQ FUEL, Issue got worse.
So we incrementally went down.
Was at 6.5 with my 450cc injectors.
Went 6.3, 6.0, was getting better and better, all the way to 5.6.
Now it pulls quite strong the whole way.
My LC1 Gauge reads alot leaner, still safe but am assuming the LC1 Sensor needs to be recalibrated.
Perhaps the calibration was lost and then when autotuning it just went to town FUEL wise and was over fuelling to death.

So will get the LC1 out and recalibrate and see how i go.

so finally got a chance to pull the LC1 out and recalibrate.

Issue is obvious once i looked in LOGWORKS.
I am getting the wrong readings at the analogue gauge and Tunerstudios.

https://www.miataturbo.net/attachmen...ine=1332990954

I am actually running at least 1.4 leaner than what TS and the gauge thinks.
Explains why it idles so well at 15.. oops.

So am now trying to get Tunerstudios and my G5 gauge to read what LOGWORKS does.

Picture says you are richer...

BUT - why do you trust one reading over 2 other readings? Just a thought...

I have very similar problem with my 1.8 turbo miata NA, so i don't create new topic.

The problem began when my car don't start at all one day, starter was spinning flywheel but engine don't evan cough, after one hour engine start whitout any problems, i don't do practicly anything, it was running at idle very well, but when i start moving it run very bad, idle goes teribbly low, when i put trottle down there was exhaust shooting.

After night engine run perflectly well and i drove around 40 miles without any issues.

Suddenly during driving engine stop and the same story, engine wont start for one hour. In this time i checked gauges in Tuner Studio and all was fine and i swaped a CAS from my friend car, it didn't start with the swaped CAS and my CAS works in friend's car.

After one hour engine started and stay in this condition to this day. Huge lack of power when boost is rasing above 0, acceleration is worst than standard N/A. it is running quite normal when i'm adding trottle gently in low range of RPMs (max 3000 RPM).

I changed also MapSensor from dual 400kPa, to singel 250kPa, couse i saw in log that boost is incredibly high in low RPM (120kPA in 2500RPM). After Map Sensor change log looks better, engine runs better at idle, at full trottle still have the same lack of power, but it don't shoot from ehaust so much.

Here is link for MS logs
http://www.pagadesign.net/logs.zip

I checked also fuel pump, i swaped it, but nothing changed. I checked also wiring for CAS and stuff like that, all good.

Have you any adviced?

Dweezle how you story with your problem end?

Patryk, I looked at your logs. Something is definitely wrong. Is it actually going into boost or is your MAP reading off? It is going WAY rich under acceleration.

What part of the world are you from?

I'm from Poland.

Please download again zip package.

I uploaded wrong file 'new map sensor driving.msl' yesterday, now it's correct.

Boost in this file seams real in my opinion.

At 1826.422 it goes super rich under acceleration, just like I saw on the other logs. That is not good at all.

Then it looks like it hits the overboost protection at 1826.562, which makes it the computer cut the fuel off. Do you have the overboost protection set for around 200kpa or 14-15psi?

yes i have overboost protection at 200kPa.

What could be a cause of this super rich moments?

Here is my msq file, from time when car was working properly. Now it has changed ASE and idle section in fuel and spark, but it doesn't matter in this case.

http://www.pagadesign.net/msq.zip