Car won't start on first try???
 

My car just recently started acting up on start-ups. It will NOT start on the first cranking try, no matter how long I let it go. When I let the key go and try it again it will start EVERY time on the first crank of the second try. I am pretty sure it has something to do with the cranking fuel but don't know where to start. I have HP Tuners so any advice on where to start looking would be greatly appreciated.
Thanks
Matt

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Same question here... TTT

I have the same problem

Almost sounds like no fuel pressure is in the rails at startup and the repetitive turning of the key is priming it enough to start. I would connect a fuel pressure gauge to the rail and check it. The GM manual calls for 55-60 psi with the IGN in the ON position (not the engine on). You also need to leave the IGN in the ON position for 8-10 minutes to make sure the fuel pressure does not drop down past 50-52 psi.

Key on engine not running: 48psi.
Key on engine running: 62psi.

Key off power still on: 48psi.
Key off power off: Slow bleed down of pressure.

Edit: This is not a stock fuel system...

Ok, did a little research. First check your IAC park position tables, should be stock setting or lower, and if you are cammed up check afterstart enrichment table, t could be dumping too much fuel on the initial hit of the key for a cold start. Also check your open loop FA table for enrichment rate may need a little adjustment. Last but not least is your base spark advance, you need a little more timing to get things kicked off from the door.

If you do a search on idle tuning red hard supra has a good write up to what to look for on startup.

Thanks..

May be bad Cam Position Sensor.

i have same problem too :( but only on cold days

but this would only be the case 50% of the time, and there would be a SES light.

Did this fix your problem?

Yes it did....

I have the same problem. It doesn't happen everyday though, just at certain time of the day, like in the evening... weird.

Mine was they same way. It only did it occassionally, but it seems to be cured now.

Also check cranking VE...

Ok, tried something a little diffrent last night. I took the cranking ve, iac park position, after start enrichment and the open loop f/a tables back to stock.
Then I changed the initial startup airflow table to from 1.0 to 1.8 in the middle three columns, and then increased the choke airflow time table from .5 to 1.0 and saved the file in hpt. I uploaded it to the ecu and started the car and worked like a charm.

Remember if you changed your open loop f/a tables for some reason other than startup then don't put those back to stock but rather put them back where they were prior to trying to correct the startup problem. The same applies for any other tables that were changed.

This seemed to work better for me rather then changing all those other tables. Give this a try and see how it works.