Greetings,

I have been trying to solve this problem on my own through research and trial and error and I have gotten to the point to where I need assistance.

I have the MS3X which I assembled myself. I followed the instructions completely on trubokitty and have been having problems getting my 95M to crank. Sometimes the car cranks on the first attempt, sometimes on the 10th or 11th and sometimes it takes an hour or so to crank. I believe this correlates to engine temperature. I understand this is a very common topic but please bare with me, I have tried researching and reading other forums but seem to have gotten nowhere.

A little about the car:

• 1995 M Edition
• Jackson Racing Supercharger w/ charge pipe
• K&N "cold" air intake
• EGR Delete/block off (the pipe kept breaking, ive since replaced the motor mounts but kept the block off)
• Wideband O2 & Gauge
• Boost Line & Gauge

I installed the IAT sensor right before the air intake manifold, deleted MAF Sensor.
I verified timing using a timing light and fixed timing.

Some things to note:
When the car refuses to crank, sometimes the crank never happens and the starter just spins.
When the car tries to crank, it doesn't seem to try for very long. I believe this is related to the ECU losing RPM sync.
When the car does crank, it runs well except for when the car gets warm I get a bit of idle hunting. Not much of an idle hunt, but still an idle hunt. Would love to get help determining the cause of this, but that is a later issue for me.

The car crank/started fine on the stock ECU.

Ive read about some people needed to adjust pot values. I measured R56 today and its outputting 4.9V, which I assume to be correct (or at least close to the correct value of 5V).

I have attached my current tune as well as a composite log, both taken today.

Thanks for taking the time to read this post, I appreciate any and all help, especially productive criticism. I have made some adjustments to the base tune provided.

 

Gonna need further clarification on what you mean by "Refuses to crank" Do you mean it doesn't crank over at all? Or it just doesn't start?

 

hey! Thanks for replying! When i say it refuses to crank, the starter just spins and quits. No turnover, no crank, nothing.

 

Sounds like a starter problem, especially given how intermittent it is and the fact it eventually just works. If it was something tune related then it just wouldn't work at all. I know you said it worked on stock ecu, but it sounds like at sometime between you being stock and installing your ecu your starter has begun to go out. As for your rpm sync theory, the car could have NO crank angle sensor (i.e no rpm sync at all, ever) and it would still crank and crank and crank, just never actually start.

 

You have a lot of cranking advance, currently 18, your note says "originally 5". Try 0 or even -5, and see if it gets better. The only thing this fixes, is when the engine tries to fire before TDC, so it stops it's rotation, sort of like trying to close a door before you walk through it, you'll stop.

However, if the starter is in fact doing what you're describing, it's nothing to do with the ECU, as the starter is just a motor with a few relays and connections between the key, battery, and starter, nothing else.

As for the idle hunt, turn idle VE off until you've tuned the idle region of the VE table, and more than a 100rpm from target is a pretty big difference, and you've only got 1 degree +/- of timing control within 100rpm. I typically use 10.

 

thank you foe the response! My apologies for the delayed response. I have adjusted the cranking advance to -5 and still seem to be having problems.I did this when you first posted so i gave it about a week to try out before i replied. Ill have some time to mess around with the cranking advance a bit more today and tomorrow.

I have disabled idle VE but cant seem to find the 1 degree of timing control you mentioned. Would you mind pointing me in the right setting location?