I finally got the mustang started on a good start-up tune. I haven't driven any where yet as there is still some to do. The car starts on the first try without giving it gas every time. But it always idles around 1500-1550 rpm. According to my cam card idle should be around 850. I don't see any obvious vacuum leaks. TPS in the BS3 says 6 %. What would you guys suggest checking next? It certainly smells rich in the garage. Thanks a bunch.

Sean

 

Sean,

Log it and send me the log and the .big file. I'll fix it in 2 seconds.


DCB

 

Thank you for the kind offer, Don. I would prefer to work through it myself with tips from everyone. That way I actually understand what is going on with my car and I can continue to utilize the stand alone. Plus, I would have to pester less.
I backed the throttle screw out until it idled at about 1000 rpm and then it started to surge between 900 and 1700 rpm. Should I just bring the idle back up until it is stable? Or should I also shoot for a proper afr and vacuum? Oh, it also does not like to start once the car is warm. Too much fuel on warm start?

Sean

 

make sure in your operating configuration that the "max tps for idle" is set correctly.
when you move the throttle blade screw, the value on the tps sensor will change. so... you need to set your idle screw to where it will idle pretty well--(which it sounds like you did) then, see what the idle tps is reading in the bs3 and compare it to what value you have in the operating parameters configuration screen. you should set the "max tps for idle to about 5% and then move adjust the tps sensor position so that it reads BELOW 5% when you are off the throttle and idling. that should help.

 

Ah, the good doctor. Thank you Lee. I know you have BS3 experience and was hoping you might chime in. Anything else I should be immediately aware off with the base start up tune? Thank you.

Sean

 

i run closed loop above 4500 rpm. it makes dialing in the idle and part throttle a bit easier. do you run an IAC motor??

 

I do have an IAC. The only reason I am not adjusting the TPS is the warm start issue. I might need to add a second ground at the engine.

 

0 out the map vs fuel table in the warm up menu above 125 degrees and see what it does on hot start

 

you still need to get the tps set 1st. if the bs3 is looking up a part throttle cell while at idle you are going to have surge and starting problems.

 

Roger that. Thank you for the help.

 

Was already done. I can't get the car to start now. Hopefully I can soon and then get the tps set correctly.

 

Car did start and I think I got the tps set correctly. Still no hot start. I did notice the cranking rpm is only 50. Bad battery or crappy starter? Both are new.

 

make sure your crank trigger is properly adjusted to the right air gap, had my car running for months and one day it just wouldnt start i hooked up the lap top only to see i wasnt seeing much rpm while cranking over. dont know why it ran before and then just stopped that day but closed the gap for the sensor it fired right up.


sammy

 

Thank you, Sammy. I will measure the air gap and see whats up.

Sean

 

Well, the crank trigger gap was .06. Should be fine. More detective work required.

 

what does it read at cold idle?

 

The tps? Under the AFR table it reads 5.5 and under the idle throttle table? it is between 0 and 8, so about 4. I need to open the holes up in the tps sensor to get more play.

 

im not too familar with the bigstuff3. usually in software for ecu's they have a tps recalibration feature to set idle and WOT and at idle closed throttle its supposed to read 0%. i see the "max tps% for idle" in the operating parameter configuration. is the tps recalibration feature just not needed for the bigstuff3? also whats the throttle follower values for for 0-56% tps?



EDIT: nevermind i read the manual..doh


whats the tps read at the bottom of the dash?

 

Well, after reading through the manual again and tinkering, the car idles pretty well at about 850 rpm and starts repeatedly when hot. It was just a combination of a few things being off. No idle spark adjustment turned on, tps set incorrectly, etc.. I will try and fine to it with battery voltage and injector phase angle soon. Thanks for all of the help.

 

2 Very important items for good idle.