Mine did that for the first week or so.....it slowly kept getting better as the PFC learned the car more and more. But when I first started it, I let it idle for about 30 minutes with the AC off.....then 30 minutes with the AC on.....that helped it learn the load of the fans coming on and off better. Then I just drove it.....and it just kept getting better. You will pull up to a stoplight and it would surge up and down like that for about 10-15 seconds, then calm down and be good to go.....then the next time you came to a stop, it would do it again....over and over and over....till one day, it didn't do it any more. Congrats on getting the car running. Can't wait to see it and hear it.



Good Luck.

LOL https://www.nopistons.com/forums/pub...#>/BURNOUT.gif



I'm guessing it was either the injectors I replaced or the extra battery ground I added.. Who knows.. WHO CARES!!! It runs! https://www.nopistons.com/forums/pub...IR#>/bigok.gif

Thanks for the info! I'll just give it a while to smooth out.. No AC, so I guess I don't have to do that one.. https://www.nopistons.com/forums/pub...#>/biggrin.png

I'll call you today sometime.. Gonna let it get to operating temperature and see how it acts.. https://www.nopistons.com/forums/pub...#>/biggrin.png

Ok.. So I let it idle for like 15-20 minutes. The surging didn't stop. The car is undriveable like this... If I try to push the gas it kills the car.. https://www.nopistons.com/forums/pub...1047683561.gif

that happened to me at first with my PFC



i know there are a few main settings u gotta change when u go single. are u just installing the pfc now or did u already have it with twins?



side note my car stalled from idle a lot the first day with the new ecu but by the 4th or 5th startup it was idling fine

HUZZA

I thought it would start to smooth out but still hasnt..



I was told that I can start the car and let it lear idle without changing anything..



I have not adjusted the idle screws yet, but will.. The car is so goddamn loud I had to quit for the day with a headache.. https://www.nopistons.com/forums/pub...1047683358.gif

Member Boostn7 can help you with this. The reason your PFC is doing this is when you have a ported motor, the fuel cells fall under a different spot on the map at idle(remember ported motors make less vaccum at idle, also at the same time fuel atomization lesses with a bigger port due to less airflow velocity at low rpms with a ported motor) that will cause the PFC to hunt because the fuel cells in that range need to be adjusted, the only way to correct this is by tuning the idle properly with a Datalogit.

Also DO NOT ADJUST YOUR IDLE AIR SCREW THIS IS NOT THE PROPER WAY TO FIX YOUR PROBLEM!!!!