Microsquirt Cold Start Issues - 408w

[John-alphaEFI]

Hi everyone,

New too the forum and glad people still use this platform in 2021.

I am chasing down a cold start issue with my 408w.

The car has :

Microsquirt v3

80lb deka injectors

90mm throttle body

Stock ford IAC

walbro 450 pump (holds fuel pressure at the rail on prime fine)

Stock distributor and tfi module

What the car does:

It cranks forever , probably 15-20 seconds then finally lights off and runs good .

What I have tried:

I have tried pressing the gas pedal in and out too see if it was flood clear or not opening the iac enough too start - no change

I have tried differnt cranking settings ( no change )

I have tried pulse width ( no change)

I have been up and down the spectrum of cranking pulse (sometimes it lights off but by then its been cranking over and over and over)

I have got the car warmed up and tuned some VE and idle too a nice 14.0 and it is fairly smooth driving

I feel like i am missing something here on the cold start issue, it could be cranking pulse but i just dont know why it takes forever too start.

When I first started this car on stock injectors it fired right off on a base map the ecu came with

[John-alphaEFI]

I have my msq file and log but i don't see a way too link it here ?

[alphaefi]

Figured out how too upload

Tune File:

Attachment Deleted

Data Log of me cranking it cold

Attachment Deleted

[Stinger]

The .xml file isn't a tune file (should be .msq format). Upload the msq.

Have you tried key on/key off a few times before cranking in order to give it extra priming pulse? If that helps then double or triple the priming pulse setting (depending on how many times turning the key works best).

[wesk]

Why is trigger angle offset set to effectively 0? That means cranking advance will be the same thing.

It is spinning VERY slow. Battery voltage dropping to a point it shouldn't run. You have a power or ground issue. Where is the microsquirt harness grounded? Where does it get power? Same questions for the engine. Where is the battery?

[wesk]

Also, either air or coolant temp is messed up. I don't know which one (likely coolant unless it is really 2 degrees F).

[alphaefi]

Sorry about that, here is the MSQ file. Attachment Deleted<---- Correct File

Battery was low on that cranking, I put the charger on it and it spun over fast.

The Air Temp Sensor was unplugged, I plugged it back in but still no change on the start. Is Air temp even used for the start up sequence  ? I know for sure coolant is, I calibrated that sensor in tuner studio and it reflects correctly on tuner studio in the graph like cranking pulse width/coolant.

I am not sure why trigger offset is 0 ? Maybe the tune file above will give a hint too why ? I just uploaded the correct file. 

Thanks everyone.

[alphaefi]

Forgot too say, my grounds are correct, just a low battery which is reflected in the log.
Engine too chassis
Battery too chassis
Microsquirt too Battery

[alphaefi]

The procedure I followed to originally set timing on the car.

Tuner Studio - Set too Fixed Timing Mode
Started the car
Timing light on the damper I set the distributor as close as I could too 10 degrees
Tuner Studio - Using the timing wizard I set it too 0.5 which was just enough too bring the timing light on 10 degrees exactly
Tuner Studio - Set it back too use timing table
Verified 22 degrees shows on the damper while idling

Did I mess that up ^ I noticed a 302 base tune i had has 10 degrees offset set in the wizzard

[Stinger]

The wizard adjusts the trigger angle. Don't use the wizard with TFI. Just set it with the distributor and a timing light. Put offset where it should be and then just set to "fixed timing" and 20 degrees BTDC, and match it at 20 deg BTDC with the light on #1 while the engine is running. Put back to "use table" when done.

So it's 2 deg F where you are (or it was when you took the log above)?

[alphaefi]

It is actually 30s where I’m at now. I’m in southern Maine .
When I turn the key on the dot hovers over the 30 degree cell on the cranking duty map.

Not too sure why it shows up at 2 degrees in the log

[Stinger]

Adding MAT (manifold air temp) and CLT (Coolant Temp) gauges to your TunerStudio screen would be a much more accurate means of viewing the temp readings than seeing what dot it's nearest to in a map. If these readings are inaccurate it will never start correctly. What it's showing in the log is what it's reading and what it's sending to the ECU.

[alphaefi]

Attachment Deleted <-- Another log where it starts up

Going too fix the air temp sensor today - although i don't thing air temp is used for initial cranking

Coolant temp sensor is reading correctly, looks like its getting fuel with the PW1 and 2

At the beginning of the log, it looks like my battery V is only at 8-9volts..probably not enough too fire the coils correctly. I'll try another battery or charge that one more.

In my second log, it fires right up where you see i shut the car off after it finally started, battery was charged from the alt.. I am wondering if somethings constantly draining the battery.

[wesk]

Coolant temp shows 16 degrees in log. Are you sure that is correct. It will likely start better if you set the timing how we prescribed. It can only crank with 0 degrees that way you have done it.

FYI, engine and microsquirt having different ground potential may or may not cause issues with spark control during cranking.

[alphaefi]

I will address the air temp sensor and test the coolant temp sensor for accuracy . 19 degrees does sound accurate, its been very cold here at night 10 degrees or so and 20s-30s in the morning.
I will also reset timing like you guys said and report back with all of those things.

Once its fired up , it runs good but let me start with those action items.