I think it might be in the tune but i'm really not sure
#1
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I just rebuilt my motor I have 8.5:1 compression ratio and a lightweight flywheel. well basically now that I have the engine back in its very difficult to start it backfires on the exhaust side and sometimes it seems like it fires and tries to turn the motor backwards..i've checked my timing belt and checks spark timing and everything seems to be good. once it starts in runs perfectly but it seems the easiest way to start is by push starting it...any ideas on what might be causing this problem? I have about 10 miles on the motor.
#8
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Looking through the tune; Your cranking PW @ 105*F is funky, there is a dramatic drop at that point. It could be causing the MS to interpolate around that wrong, leading to a hard start.
Did you scale the Req Fuel?
Also your AFR table looks weird along with the IGN table; though those will not cause the issue you're having. The tune looks like it could use some work.
Other than the tune being the issue, can you check to see if you are infact getting spark on turn over, ever time?
Do you smell gas when you try to turn it on and it fails?
What is the ambient temp?
Is everything grounded properly and/or plugged in completely?
Can you check your plugs for fouling or any other issues?
Did you scale the Req Fuel?
Also your AFR table looks weird along with the IGN table; though those will not cause the issue you're having. The tune looks like it could use some work.
Other than the tune being the issue, can you check to see if you are infact getting spark on turn over, ever time?
Do you smell gas when you try to turn it on and it fails?
What is the ambient temp?
Is everything grounded properly and/or plugged in completely?
Can you check your plugs for fouling or any other issues?
Last edited by HexRX; 11-19-2015 at 07:47 PM.
#9
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Looking through the tune; Your cranking PW @ 105*F is funky, there is a dramatic drop at that point. It could be causing the MS to interpolate around that wrong, leading to a hard start.
Did you scale the Req Fuel?
Also your AFR table looks weird along with the IGN table; though those will not cause the issue you're having. The tune looks like it could use some work.
Other than the tune being the issue, can you check to see if you are infact getting spark on turn over, ever time?
Do you smell gas when you try to turn it on and it fails?
What is the ambient temp?
Is everything grounded properly and/or plugged in completely?
Can you check your plugs for fouling or any other issues?
Did you scale the Req Fuel?
Also your AFR table looks weird along with the IGN table; though those will not cause the issue you're having. The tune looks like it could use some work.
Other than the tune being the issue, can you check to see if you are infact getting spark on turn over, ever time?
Do you smell gas when you try to turn it on and it fails?
What is the ambient temp?
Is everything grounded properly and/or plugged in completely?
Can you check your plugs for fouling or any other issues?
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