95 4.3 TBI spark table info

[ironwill11]

are you positive the idle problem is in the tune? have you checked for vacuum leaks? a spray bottle of soapy water can save a lot of headaches. a bad diaphram in the brake booster can drive a man crazy chasing idle problems...... still seems the ms should run with the bypass disconnected, maybe have the ignition module tested, check voltage at the module........ they do some funny things if ya get one that is a little flaky or the voltage is off...... i have seen factory modules with 20-30 degrees difference to one identical to it............

i don't believe the timing light will tell you much during cranking, too much variation due to compression,starter and other stuff......

skandolis,

I am not sure if the idle problem is in the tune. The idle used to hunt prior to megasquirt. The folks at diyautotune told me it megasquirt would help me out. The MS does try to run with the bypass disconnected. It cranks and stumbles once or twice, but can't stay running.

As far as vacuum leaks, I spent a year looking for them. I found a number of people online that had the same idle hunting as I had and replaced many parts looking for vacuum leaks to no resolve. The most damning evidence that suggests there is no vacuum leak is that when hooked up to my laptop my MAP is very constant.

I am at the very beginning of the tuning process. All my tables were generic tables created by tunerstudioMS (Very difficult software to used since all the material in the manual references a tunerstudioMS version that does not exist anymore. I have no idea how to set it to fixed advance. I know that if I increase the trigger offset the idle will come down a little (up to around 28).

I do know that as it warms up it tends to gradually increase the idle. Only once did it act like it should and start around 1200 rpms and come down to 800 rpms. Then the next day it would not start at all unless I increased the advance.

I have played around with the timing so much that I wanted to make sure I had my timing marks aligned properly but I could only do it by hand.

Will

[ironwill11]

Hello everyone,

Did not get a lot of work done due to a nasty sinus infection, but it gave me time to think.
Since there is very little information on getting started with megasquirt, I have decided to hook up the GM wiring harness.

First question: I have the two 7477 ecus. Any recommendation on another ecu that I should use for a relatively stock 95 4.3l TBI from an s-10 blazer?

Follow up question: Can anyone point me in the right direction to getting started with tuning whatever the recommended ECU might be?

All help is appreciated.

Will