So a bad tune will pop even a stock motor. Help me learn so I can boost. K thx... - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MEGAsquirt A place to collectively sort out this megasquirt gizmo

Reply
 
 
 
LinkBack Thread Tools
Old 05-30-2013, 11:33 AM   #21
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

From: MS2/Extra Tuning guide

Quote:
Before tuning decel [or accel], make sure you have your VE table close to correct first! One way to do this is to get the VE table set up by setting the TPSdot threshold setting very high (250 kpa/sec or 250 %/s, something like that) so that TPS enrich/enlean never kicks in. Then, (in steady state) set up VE table.
I am going to try this on the ride home. I am wondering what the drivability changes will be though.

EDIT:

From: http://www.diyautotune.com/tech_arti...ent_tuning.htm
Quote:
If either Accel or Bit 7 are active, that's a Accel event and AE is adding fuel. If Decel or Bit 8 are active, that's a Decel event and AE is pulling fuel if configured to do so. (Accel and Decel are used for TPS Driven AE, and Bit7/Bit8 are for MAP Driven AE).
This leads me to believe that the change in MAP was causing me to go into AE when the throttle was still. I changed the values in the accel enrichments page to be 100% TPS, which should completely remove the Bit7, Bit8 nonsense.

Last edited by Chiburbian; 05-30-2013 at 11:49 AM.
Chiburbian is offline   Reply With Quote
Old 05-30-2013, 12:33 PM   #22
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Yes, if you have a VTPS, use 100% TPS accel enrichment. MAP signals can have a bit of noise and it can be enough to trigger an accel event.

In general, to tune accel enrichment, start with litttle to none and add just enough to get over any lean stumbles you detect. I think you'll be surprised how little you need once the VE table is in good shape.
hornetball is offline   Reply With Quote
Old 05-30-2013, 02:40 PM   #23
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

By the way, I feel like I have some dead spots in my most recently posted tune. Dead as in so far rich or lean that VEAL can't properly compensate. Can you guys take a look at the overall shape and let me know if it is reasonably close?

Also, why are my fuel loads higher numerically (richer) than most maps I have seen? DIYautotune's base map is lower (starts in the 30s I think), Y8s tune which is what I used as base for my VE map starts in the same area. The VE map wizard wants to start me off with a much more lean map. What is going on here?
Chiburbian is offline   Reply With Quote
Old 05-30-2013, 03:29 PM   #24
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Can't read your msq. Is it relatively smooth, or does it have big dips and peaks?

Don't worry about the VE values. They are non-dimensional and work in conjunction with your "Req. Fuel" (multiplied together). There is a maximum value (255 (8-bit) for MS1, not sure about MS3), but as long as you are comfortably below that, you're OK. Having larger numbers is actually better because your resolution becomes finer.
hornetball is offline   Reply With Quote
Old 05-30-2013, 03:52 PM   #25
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

Quote:
Originally Posted by hornetball View Post
Can't read your msq. Is it relatively smooth, or does it have big dips and peaks?
Well, some of them looked out of place compared to the nearby "terrain."

I freehanded the map to lower the peaks and raise the dips. I will just be gentle with it when I drive and see what happens. I can't imagine it would be too far off, if the value is bigger than the one on the left, and lower than the one on the right, I imagine it has to be in the right ballpark right?
Chiburbian is offline   Reply With Quote
Old 05-30-2013, 07:26 PM   #26
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

VE tuning is an iterative process. I usually just keep doing it until the changes being made by VEA are kind of in the noise range. There will be some areas of the map where VE will decrease with RPM. This has to do with intake runner length and getting to RPM's where flow is starting to choke. But there shouldn't be any really big dips or peaks -- just smooth those out a bit.
hornetball is offline   Reply With Quote
Old 05-30-2013, 10:13 PM   #27
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

New log. Same crap. (actually, after looking at the log it doesn't look too bad, but it felt worse than it looks on the log, in my opinion)

I am going to work on my grounds tomorrow, but this is starting to tick me off.

AE is off (correction, was set to 250, I was getting some AE - I changed settings to 2500). EGR unplugged. Air intake temperature sensor located to just prior to butterfly.

I wish I didn't have to work tomorrow because I really want to lick this.

While grounds will be fixed for EGR and maybe even ECU, I can't see how bad grounds on the wideband can cause it to be this bad.

However, it definitely DOES seem to get worse when any of the fans are on, if I roll up or down the window, or when I turn my headlights on.

Any ideas?
Attached Files
File Type: msl 2013-05-30_18.54.51.msl (1.92 MB, 52 views)
Chiburbian is offline   Reply With Quote
Old 05-31-2013, 09:39 AM   #28
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

With ALL correction off - No AE, no EGO, no nothing - car ran as good as it has in a long time.

Once indicated intake air temperatures got about 10 degrees above ambient I started using VEAL. I tickled each cell and let it do its thing. Whole map smoothed out, and it I was pretty happy with it. I stopped off at a gas station on the way in and burned my tune, saved the file and went inside.

Now that I had a map that I was pretty happy with, I decided to mess with stuff that I know had been giving me fits.

I did a short log attached below that shows what happens when I do stuff like turn my headlights on, turn my a/c on, etc. As you can see, it really screws with stuff.

I am half wondering if the ground from the "engine ground" tie-point (I heard one exists correct?) on the fender to the engine itself is corroded and failing. I have seen that on stock cars before where stuff gets all goofy and it turns out to be the braided ground cable.

I turned on VEAL after the gas station and by now the engine was getting pretty hot. VEAL started fattening up my map significantly with the fans on, which made it bog sputter and nearly stop. I turned off VEAL and reverted to the map I was running when I stopped at the gas station and drove the rest of the way to work on that map. Everything was great. I have a log of the entire drive but it is too big to attach here and nothing is all that interesting.

So, either it has something to do with the alternator load being so high that it throws everything off, or a ground issue on the wideband, ECU, or both.
Attached Files
File Type: msl 6.13.02idle_ac_etc.msl (476.6 KB, 53 views)
Chiburbian is offline   Reply With Quote
Old 05-31-2013, 11:28 AM   #29
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

The ground strap between the engine and chassis bolts to underneath the brake booster. That area is corrosion-prone. Easy to check and clean.

Nonetheless, you want your ECU and WBO2 grounds tied to the engine block.

You might need to mess around with coolant-related air density, although I would definitely do the grounds first.
hornetball is offline   Reply With Quote
Old 06-01-2013, 07:59 AM   #30
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

Yesterday stuff took a bit longer than I expected. I hope I will finish this weekend, especially considering that I have to work today and tomorrow. (overtime though!)

So this is what I found. I had paper notes on my build that I couldn't find, so I pulled my jumper harness and reverse engineered the DB25 that I had installed to handle stuff like boost solenoid, wideband in, etc. I created a spreadsheet specifically for that connector to keep it straight.

Turns out I had run all five "good engine ground" lines to the DB25 from the 3x, but only two on the main connector. From there, NONE of the "Engine Ground" wires made it to the engine. The only "engine ground" connections I was using (through the stock harness) were ECM ground, PCM ground(?), and fuel injector ground (aha!?)

Since I was sharing grounds with the stock computer and I don't know how good the connections are, this seems like a good candidate for being the cause of my problems. If nothing else, it is the way it should have been done from the start I imagine.

While I am at it, I plan on running the wires for sequential ignition and pigtailing them and also bringing the wires through for the boost solenoid, the boost sensor, and oil temperature sensor. I will also be wrapping them and placing them in convoluted tubing to make it pretty.
Chiburbian is offline   Reply With Quote
Old 06-02-2013, 10:09 PM   #31
Elite Member
Thread Starter
 
Chiburbian's Avatar
 
Join Date: Feb 2008
Location: Gilberts, IL
Posts: 2,159
Total Cats: 131
Default

Finished up my project today. Ran four leads to the back ground point, and two leads to the front ground point. Basically it was three from the MS3 and three from the 3x board. I also moved my O2 sensor to it's own engine ground with a quick disconnect so I can easily add additional gauges just by using a new connector. I will try and take pics tomorrow, but I also spent the time to wrap the bundle in convoluted piping so it looks all nice, and I also added a quick disconnect for both the air intake sensor and the EBC solenoid which isn't installed yet. Easier to set up the wiring in advance and it looks pretty slick. I would have ran pigtails for the coils (COP or LS2, haven't decided yet) but Radioshack was out of suitable wire and I was on my last spool. Matter of fact I burned my last spool finishing this project.

I then went out for a drive and... I have my reliable and fun car back! Ran very well, no hiccups at all. I have EGO and accell enrichment off for the time being. I even turned on the A/C just to force a load on the engine and aside from the physical load on the engine, no issues at all.

I do unfortunately have a couple pending issues but I will move that to my build thread.

Thanks for the help!
Chiburbian is offline   Reply With Quote
Old 06-02-2013, 10:56 PM   #32
Junior Member
iTrader: (1)
 
Join Date: Apr 2011
Posts: 119
Total Cats: 1
Default

Quote:
Originally Posted by Chiburbian View Post
Finished up my project today. Ran four leads to the back ground point, and two leads to the front ground point. Basically it was three from the MS3 and three from the 3x board. I also moved my O2 sensor to it's own engine ground with a quick disconnect so I can easily add additional gauges just by using a new connector. I will try and take pics tomorrow, but I also spent the time to wrap the bundle in convoluted piping so it looks all nice, and I also added a quick disconnect for both the air intake sensor and the EBC solenoid which isn't installed yet. Easier to set up the wiring in advance and it looks pretty slick. I would have ran pigtails for the coils (COP or LS2, haven't decided yet) but Radioshack was out of suitable wire and I was on my last spool. Matter of fact I burned my last spool finishing this project.

I then went out for a drive and... I have my reliable and fun car back! Ran very well, no hiccups at all. I have EGO and accell enrichment off for the time being. I even turned on the A/C just to force a load on the engine and aside from the physical load on the engine, no issues at all.

I do unfortunately have a couple pending issues but I will move that to my build thread.

Thanks for the help!
I hate grounds... They can introduce so many gremlins...glad you got it worked out though? Sounds like you're doing the wiring right! My diy wiring skills need work...
event is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
WTB MP62 (Hotside) (NB2) Rick02R WTB 3 01-03-2016 08:18 PM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM
Are my coils failing? viriiguy General Miata Chat 5 09-28-2015 08:39 PM
Missing/knock at idle, can someone point me in the right direction? Mikel MEGAsquirt 4 09-28-2015 05:46 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 03:48 PM.