I'm having issues idling with the car after the engine was built. On the initial startup, we had a major vacuum leak so the car sounded like it had nasty lope to it and would stay alive. Even in closed loop it would run.. We since plugged that leak and now once the car gets out of open loop, it will not stay alive unless the pedal is pressed to about 5%.

The vacuum leak was the fuel system evap to the intake on driver side.

It's a 5.3L with a TSP 224R cam. Do I need to drill out the hole in the throttle body blade to allow more air in? I've had a local tuner out to adjust the tune as well.

Any input is helpful.

Thanks,
Jordan

 

Your tuner should be able to fix with a tune. It sounds like you need more idle airflow in the tune.

 

I'll double check with him this weekend. I really just need to break down and buy HP Tuners. :/

 

I wouldn't drill the TB, not with a 224 cam.

Tune needs to be adjusted if there are no more vacuum leaks.

Make sure the tuner logs the car from a dead cold startup. You only get to do once every 6-10 hours or so. Your tuner needs to set the running airflow or RAF and begin tuning the VE table. If you didn't swap injectors, your fueling info is correct and your tuner just needs to get airflow and A/F right. Spark needs to be upped at idle as well by probably 2-4 degrees. Possibly more.

Make sure the tuner tunes the cranking VE table as well and is inline with the Primary VE table.

There's a whole bunch of other things that could be tweaked as well with the follower/cracker, adaptive idle airflow, adaptive spark, etc. But most of that isn't needed for a small camshaft. Just get the tuner to get the air, fuel, and spark correct and it'll idle. You may need to open your throttle body blade up a little to give it some more airflow at idle. But the IAC counts will let you know if you need to open it some more.