regorih

Guys I'm working 99'C5 with heads, cam, bolts ons, LS2 TB, and FAST 90 intake.

I was able to get the car to idle but once I put the car in drive or reverse it stalls out and dies. Anyone been down the road that can point me in the right direction?

tblu92

So many mods all at once--the greatest issue will be using a 99 ECM and a LS2 T-Body
What about your MAF ?? Is it a stock 99 ? or something newer----I have EFILIVE so I can't open your file---
However With your hds/cam set up These are some of the "must do's "
Knowing your can specs will help but you always need to ADD timing to the "base spark" in both P/N and in gear--Stock is usually about 18* Asssuming you have a mild cam I would set the base timing in the start up/idle areas to about 1000 RPM to at least 23-24*
Then you need to add some idle airflow again in both P/N and or in gear to the entire "desired airflow table" Start by adding 15%---If you go too far then you'll get the opposite affect--a hanging idle---then simply back out some % til OK
These are the 1st 2 things to do to correct dying surging---
Is your car a manual or auto ???
Another commom issue is having the engine try to die when coming to a stop--It that's happening let me know and I will tell you how to fix----
Finally once you sort out all these issues you at some point need to do a "crank sensor re-learn procedure" (because of your cam swap) HP should have a tutorial on how to do this---
PS: make sure once your engine has warmed up and switched
to "closed loop" that all your LTFT fuel trims are at "0" or slightly negative--
Correct this by making an adjustment using your MAF HZ table---HP should have a PID to data log this--

regorih

Thanks for the help.

I figured it out last night, sort of.

I logged my RAF and updated those cells form the information I logged from the histogram, and I increased my ETC area to 0.0395

I still need to go back and mess with timing and other parameters you talked about.

My car is an automatic so its very tricky

mowton

Not to be picky this late in the game, but that is not the correct scalar for a 90 mm TB. The value s/b .0192 and would require re-tuning your BRAF and idle trims.

The scalar tells the PCM the "effective area" of the TB so that it can calculate the correct TPS% based on its adaptive idle error correction calculations. By going to .0395 you are effectively telling the PCM you put on a smaller TB so it will employ larger steps to produce the same amount of air. If you went to the .0192 value, you would have to reduce your idle values in line with the larger area requiring smaller changes for the same amount of air.

Know it sounds 6 of one and 1/2 dozen of the other, but accurate characterization of the airflow path is required to attain the best idle control, decel/coast down operation etc.

JMHO

Ed M

regorih

Thanks I appreciate it. Whe I was scaling for the 90mm TB and tried a value of .0192 and logged RAF, I could not even get the car to stay on once fired up.

I'll have to go back and try again

mowton

Any updates?

Ed M

regorih

That could be a while since I dont have the car anymore. It's a buddies of mine and I wont see it till the next round of modifications. Last he said was that the car has been running fine.

Roger