MS3 pro Cant figure out why it wont start!

[nastychevelle]

Setup is

325ci 5.3 LS engine
Cam
AFR 205 heads
Super
victor intake with elbow and a 102mm throttle body
Twin GT45 turbo's

Injectors are modified Precision turbo 225lb/hr (now flow 275lbs/hr at 43.5psi base, Base set at 65)
Mechanical Fuel Pump (aeromotive belt driven)
Electric fuel pump as primer pump (see 65psi when cranking)

Car runs on straight methanol

Using ms3 pro with DIYautotune's plug and play harness
ALso have a versafueler wired in so i can run low impedance injectors

Ive ran all the injector and coil output test modes and everything checks out. RPM while cranking is only around 100-120rpm

Ive tried everything and i cant seem to get it to fire. IVe played with cranking advance and cranking fueling, ive tried playing with rpm to start, also tried adjusting from COP to Wasted COP to see if it was a cam sensor issue. Everything is sync'd when cranking. NO immediate red flags.

Im at a loss.

Heres the current tune file ive been trying
https://www.dropbox.com/s/cw3bqcac4spae ... t.msq?dl=0

Hopefully im just having a brain fart and its something really simple.

[93supercoupe]

When you say it runs on methanol, what do you mean? Has it ever ran on Megasquirt?

[93supercoupe]

and upload your MSQ directly, i dont have a drop box account

[Six_Shooter]

Have you checked for injector and ignition pulses while cranking?

[nastychevelle]

When you say it runs on methanol, what do you mean? Has it ever ran on Megasquirt?

Methanol is the fuel i run. not gasoline or e85.


https://www.youtube.com/watch?v=Ra4CRn9REnc


ive ran through all the test modes on injectors and coil packs.

ive even pulled a plug and cranked the motor to make sure it was firing the plug during cranking. and i know the injectors are firing during cranking because i can smell fuel.

[billr]

Post the tune and run log here as native MSQ and MSL. Have you checked spark timing, and on all cylinders?

[nastychevelle]

Post the tune and run log here as native MSQ and MSL. Have you checked spark timing, and on all cylinders?

Tune is in the first post and i dont have a run log because it hasnt ran yet. Are you wanting me to log it while cranking?

[billr]

Yes, even a cranking log can be useful. Sorry, I only look at MSQ and MSL. That link to external files is useless for help from me.

[Barton]

please add a composite log, that one shows how are the ckp and cmp behavior

[nastychevelle]

here is a cranking log from the other night and the MSQ

[billr]

Have you tried disabling the injectors and then a start attempt with a quick blast of starting-fluid, or gasoline into the intake? It would be nice to verify this is *only* a fueling issue, that the ignition is good enough for it to at least run.

Have you measured flow and dead-time for the injectors (using methanol)? When req_fuel is that low (3.2 msec) getting the engine to run will be more difficult if those injector values aren't correct.

I did some experiments with "wet" ethanol, like 190-proof "moonshine". I found that it was very difficult to get a start unless the ethanol was heated to 250-300F. Even then, the cranking pulse had to be very rich, like 500% when the engine was cold (60F). Is methanol similarly difficult to vaporize?

[nastychevelle]

Have you tried disabling the injectors and then a start attempt with a quick blast of starting-fluid, or gasoline into the intake? It would be nice to verify this is *only* a fueling issue, that the ignition is good enough for it to at least run.

Have you measured flow and dead-time for the injectors (using methanol)? When req_fuel is that low (3.2 msec) getting the engine to run will be more difficult if those injector values aren't correct.

I did some experiments with "wet" ethanol, like 190-proof "moonshine". I found that it was very difficult to get a start unless the ethanol was heated to 250-300F. Even then, the cranking pulse had to be very rich, like 500% when the engine was cold (60F). Is methanol similarly difficult to vaporize?

I have tried to start it with gas in the intake and it still doesnt try to fire. thats what leads me to believe its an ignition setup.

[billr]

Hmm, I forgot to ask the basic questions: Do you have spark in "test mode"? Have you checked spark timing with a strobe light?

[nastychevelle]

Hmm, I forgot to ask the basic questions: Do you have spark in "test mode"? Have you checked spark timing with a strobe light?

yes i have spark in test mode, i have tried to verify timing while cranking but the light doesnt blink that fast at 120rpm so it was hard to do. i dont think the timing is that far off because it ran with the holley efi no problem.

[jsmcortina]

If you haven't already, try setting the spark output to "Wasted COP" temporarily.

Sometimes the COP spark can be 360 degrees off - the timing looks good on a strobe but it won't start.

James

[nastychevelle]

If you haven't already, try setting the spark output to "Wasted COP" temporarily.

Sometimes the COP spark can be 360 degrees off - the timing looks good on a strobe but it won't start.

James

yeah i tried wasted spark, still no luck unfortunately

[Rick Finsta]

Please grab a composite log when you can - that may be helpful.

I notice he has 5* cranking advance, but the log shows 18* being commanded? The table has 30* in the lowest bin, and I can't see what modifiers in the tune would be affecting the advance during cranking.

OP when you checked your timing with a light while cranking, did you set to fixed timing? Try that and see if you're way off or something.

[nastychevelle]

Please grab a composite log when you can - that may be helpful.

I notice he has 5* cranking advance, but the log shows 18* being commanded? The table has 30* in the lowest bin, and I can't see what modifiers in the tune would be affecting the advance during cranking.

OP when you checked your timing with a light while cranking, did you set to fixed timing? Try that and see if you're way off or something.

ive adjusted the tune since that particular log. ive tried timing all over. i tried checking with a timing light while cranking but it doesnt work to well. hard to see when the engine is cranking at 100rpm.

How do i do a composite log?

[Matt Cramer]

Composite logging is covered here.

http://www.msextra.com/doc/pdf/html/ms3 ... 1-303.html

With aftermarket cranks, you can't take it on faith that they pinned the reluctor wheel on correctly; you will want to make sure with a timing light. I've seen some aftermarket cranks from companies you'd think would know better getting these off by 20 degrees!

[vw_chuck]

Why is the car turning over so slow? 100 RPM aint much. Put the battery charger or jumper on it and get it turning faster. The VR signal is not very big at 100 RPM.