Liquidog

Hey all. Current tune attached, and a short datalog of me cranking the car. Turns over but won't start, not a single sputter or catch. Just cranks.

• 1990
• 1.8L from a '94 with stock tan-top injectors
• DIYPNP
• MAF delete, GM IAT sensor
• MAF has IAT wires attached and wire jumper for fuel, pic attached.
• AEM UEGO wb02
• I believe sensors are calibrated correctly
• Removed SIG fuse prior to start
• Followed DIYautotune's documentation for setting up the fuel circuit in the DIYPNP

When I turn the key I get no fuel pump. I moved the jumper from the MAF connector to the diag box, F/P to ground. Then I did hear the fuel pump running, but the car still won't start. Cranks over and over, no start, no sputter, pressing the throttle does nothing.

Timing issue? I believe I had timing set at 14 degrees prior to MS install. During cranking though I noticed it was at 17 degrees but I figure that's just until it warms up.

any other ideas? I'm losing this garage space in a week so I'm up against it. Thanks in advance.

Liquidog

Ok, I think I figured out the fuel circuit issue.

"Jumper from “OUT” of the high side driver circuit to terminal 1C on the connector board." from the documentation. Looks like I skipped that step. I can fix that tomorrow, but since I bypassed that with the diag box jumper, shouldn't the car be starting anyways? What else did I screw up, gang?

hector

You have a lost sync reason of 38 so that is likely your issue. Do a composite log or tooth log. Maybe you just got the wiring wrong at the DIYPNP adapter board.

And not that this is your issue but raise your cranking RPM to at least 300 rpm.

Liquidog

That's interesting. Further research indicates lost sync reason 38 is often related to CAS issues. My base map
is for a 1990, but the engine itself is from a 1994. Is there a setting that needs to be changed in TunerStudio to account for
differences in CAS units between the model years?

Liquidog

This gets weirder and weirder. The ignition settings called for in the 90-93 documentation don't match the 90-93 base map ignition settings from diyautotune.

https://www.diyautotune.com/support/...3-mazda-miata/
Trigger Angle: 10
Cranking Dwell: 6
Spark duration: .7

Values in my tune:
Trigger Angle: 8
Cranking Dwell: 7.5
Spark Duration: 1.5

Seems like I should change my tune to match the documentation? Any thoughts?

hector

I really don't think the ignition settings are your problem. You are not getting a sync from the cam and crank signals. Your CAS provides both. Check your wiring. Check your pull-ups. Do a tooth log or composite log while cranking.

Liquidog

As a first step I changed cranking RPMs from 200 to 700. The car cranks and actually starts up for a second now, then immediately dies without achieving idle. The data log from this does not show a lost sync reason at all.

Braineack

iTrader: (62)

follow my writeup. that will solve all your issues. I love diyautotune.com, but their writeup and basemaps are way out of date.

Liquidog

I apologize for this request but I'm working off my phone in the garage. Could you please link to your write up? Thanks in advance.

hector

Does the datalog show it injecting fuel? And 700 is too high. Set it to 300-400. The engine could easily dip into the 700 rpm range for a number of reasons and cause it to go to crank mode again. I wouldn't discount this happening to you right now.
Brain's stuff is at trubokitty.com, check his sig.

Liquidog

It runs now. Thank you Hector and Brain for your help.

DIYautotune's docs on assembling the unit are pretty different to Brain's. But one thing I did see is I had the injector jumpers reversed compared to Brain's setup, so I switched mine. Also, I didn't have tach out set to anything, and I again used Brain's jumper for that. The car still didn't start. What got it going was Brain's base map for 90-93. I'm sensing a pattern here...

In any case, it starts up like a champ and idles, but runs like ****. Really rich and if you give it any gas, it comes back down to an idle of 400ish. I suspect my AEM UEGO isn't calibrating correctly and it's causing the DIYPNP to read wrong values... maybe? I also have a the 4-bar baro sensor upgrade and I'm not sure on what settings I need to make that play nice.

Current tune and data log attached. You guys are awesome, thanks again.

Liquidog

I did set the timing as best I could, the marks on my crank pulley are very faint, but I *believe* I followed Brain's instruction's correctly and it should be at 10 degrees. I'm confused why it doesn't show that value on the gauge on the laptop though.

hector

You have a lot of stuff going on right now so just take your time, read all you can, click on all the help buttons for each setting you want to make, etc. Everyone goes through a learning curve and the better you understand the basics the better you will understand the advanced.

Your o2 is reading 10.1 AFR solid. That is likely not right. Your baro is something like 86kpa. That doesn't sound right for Chicago. Your tune has sequential injection. Do you have sequential injection? If you don't believe the timing mark, check that the damper hasn't slipped by checking TDC through the sparkplug hole. Basics first and one thing at a time.

Braineack

iTrader: (62)

this is really only useful when upgrading to cops down the road.

you need to tell the MS you have a 4-bar map sensor and baro-sensor. IF you're not registering ~100kPa when the car is off, then it will never fuel correctly.

Braineack

iTrader: (62)

no, his tune has semi-sequential injection turned on -- while still batch, you can control the injecting timing, and use the injection timing table. But his current map has a fixed timing end-of-squirt of 10° before the intake valves open...

hector

Just trying to get my learn on. What is the difference between batch and semi sequential? IOW, batch sprays how many times and semi-seq sprays how many times per rev? It would seem semi sprays twice with one of those squirts just before TDC and the other just before BDC. Or is it once at TDC and again at TDC? I honestly don't know what "squirts per engine cycle" is referring to; 360* or 720*?

And the advantage would be longer PW's for better injector control for better idle and low speed drivability?

Braineack

iTrader: (62)

its exactly the same expect you can control where in the engine cycle you want the squirt to end, since we have a crank and cam signal.

it's just timed firing vs non-timed.

still firing one injector when the intake valve is about to open, and one when it's just closed.

Liquidog

*facepalm*
Of course. I forgot to set it back to this after I loaded your base map. That probably why the fuel and AFRs are so off. I'll change this first and see where that takes me.

And I do have a COP setup to install, I just figured I'd get the regular setup working first. Glad I have the right jumper for it though.

Thanks guys!

Liquidog

Ok - the timing is definitely correct.

Car still runs horribly. It idles about 800 when it starts up and will stay that way just fine, but with AFR of 10.0. Smells like it's running rich too. Give it any gas and it'll stumble a bit along the way, then try to idle at 400rpm. If you give it a lot of gas, it won't reach idle again at all, but just die when the RPMs come back down.

Maybe something is up with my WB02? It's an AEM UEGO. With diy's basemap, the gauge showed 14.7 and the on-screen gauge in TS showed about 10. Now with brain's basemap the gauge and TS both show 10. I got the full version of TS and attempted to use VEAL, but I don't think this is a fuel table problem, as that didn't seem to help. Seems like something is wrong with how AFRs are being measured and it's causing the car to run really rich.

Thoughts, gents?