MSefi.com read only forum (Jan.15,2018)

Am tuning MS I with 2.25. Car starts OK, but needs slight throttle opening to fire. Once started, it will keep running, but roughly. It you touch the throttle at this point it dies. After 2 or 3 tries, it keeps running. Do you think I should make the after start enrichment more or less? Is it now too rich, or too lean.?Thanks.

Sam

Yup, it is either too rich or too lean.

If you hit the throttle, and it dies, USUALLY it is a touch lean.

when it is too rich, black smoke out the exhaust, gurgly motor.

So, try to richen it up. If it gets worse, lean it out.

Samuel Powell wrote:Am tuning MS I with 2.25. Car starts OK, but needs slight throttle opening to fire. Once started, it will keep running, but roughly. It you touch the throttle at this point it dies. After 2 or 3 tries, it keeps running. Do you think I should make the after start enrichment more or less? Is it now too rich, or too lean.?Thanks.

Sam

It's a bit of a minefield. ;-) Remember you get a priming pulse and that the cranking enrichment is separate to that when it starts and runs. Generally, if opening the throttle helps it to start, the mixture is too rich. Assuming the fast idle circuit is working. If it is stalling when you touch the throttle once running, it's likely to weak.

Thanks! That is a help. So priming pulse might be too rich, and the after-start enrichment might be too lean? Is that right.

By the way, if you haven't read my comments before, Mega Squirt ROCKS. I mean this is so straight forward, and easy to learn. The support here is worth $1000's.

Sam

Made prime pulse shorter, and after start enrichment number bigger, as well as cold acell number bigger.Wide band O2 gauge helped with accel enrichment. Gauge shows nothing but count down until in calibrates itself, which takes a minute. This was no help with prime pulse, or after start enrichment, but did show my cold acceleration number could be bigger. All was improved. Engine started without touching throttle, and stayed running, even with throttle kick After a bit it was too hot to tune more. Will check it tomorrow again. This will be an ongoing process as weather changes. I will likely need to modify warm up enrichment values as cold weather arrives. Those are only guesses so far.

One problem: When you have the screen open for enrichment coefficients, the "dashboard" gauges no longer read, so you cannot follow temperature as it warms up. Is there a screen I can open which will show coolant temp and constants screen at the same time? It is a bit of a trick to flip back and forth between the two, since it seems to warm up so fast. It goes through some cells too fast to test numbers for AF ratio.

Sam