6 port motor aggressive porting and no 5/6 sleeves /ported also... It idled great right after put in... adjusted timing to 10 past stock on leading1... tps is new and calibrated via meter and led's... adjusted idle... and it seems like its getting worse idle is staring to fluctuate more and more... turn my accesories on like fan defrosteer brakes **** wants to die... idle fluctuates turn all off and it can stay steady with minor fluctuation maybe 65 rpms.... other thing> i get it to idle.... hit gas and it won't come down stuck on fast idle..... ecu is throwing codes 12-13-18 thats tps low/hi and pressure sensor.... check pressure sensor at ecu and getting correct voltage... hell even put another one in and same... so i know there both good.......the only thing i can think of is that vacume is low at idle due to porting.....anyone have probs like this ...... codes but sensors chaeck out and no break in connections tested wires at ecu. so nothing can be cut between ecu and sensor.... I'm flabber gasted..... go to pull up to a light and it wants to die or idle fluctuates.. or its stuck on fast idle..... idea's please help.... the only thing i can think of is add Safc and add a little gass at idle..... whats got me scratching my head is it idled perfect at 100 miles. now 400 miles and ???

 

Has the vacuum at idle from 100 to 400 miles changed at the same rpm and ign timing?

 

not quite sure... going to check vac in a sec be right back...

 

idle no accessories no load... 15 in vac.... but I turn on lights defroster etc.and vac drops to 12/13 in vac.... not good... is the pressure sensor able to read that low or is that why its coding...... as far as change in vac between fresh and 400 miles not sure... but it idled great i'd say around 15 when fresh...

 

Bac not working? Raise your idle to 1k and reset tps then check problem still persist.

 

Bac is not adjustable.... my turbo one is adjustable.... should i use that one.....is it swapable S4TII>S5NA was wondering about that.... never needed it on my TII..

 

either way >> if its my BAC why am i not throwing a code???
You say reset the tps you mean readjust or put within spec or is there actually a way to reset the tps....

 

Who did the rebuild and porting?
Can you do a compression check?


-Ted

 

I did the rebuild/port...... all specs were new and right on....
either way >> if its my BAC why am i not throwing a code???
You say reset the tps you mean readjust or put within spec or is there actually a way to reset the tps.... tps has been set every which way, bymeter led's etc.and checks out on resistance... how about someone local... want to help...

 

15 inHG is fine at idle on a ported motor......

Have you checked your altenator voltage?, low voltage at idle dooes bad things to cars

 

no dimming what so ever s5 alt....