S13 redtop sr has idle issues once it hits 65 degree

SON240sx Automotive
1

Just swapped s13 sr red top into s14 and i’m having idle issues. Once the cars temp hits 65*c the car will idle from 1100 to 300. I’ve fixed major boost leak, sprayed some carb cleaner into iacv and set the tps to .33volts(meters probes aren’t good). I tried to adjust iacv but doesn’t effect the idle at all. Just keeps going up and down.When i first start it the AFR is 14.6, while driving its bit rich but once i change gears it goes full lean until i get back on the gas. If i get off the gas the idle will go really low or completely die.

Anymore things i can do to resolve this issue before i go in for tune?

sr20 parts list
S13sr into s14
hks stage 1
Powerfc +MAP+AIT( tuned with s13 not s14)
gt28 71 .64
new harness
walbro
spiltfire coils
stock FPR got now

2

how do you plan on tuning? You dont’ have injectors or fpr.

Try dropping in a stock ecu and see how it runs without powerfc, maybe its just because its not tuned.

3

if its not the power fc check your coolant temp sensor

4

Forgot to mention . It’s already tuned powerfc running with 555hks inj. So far I took out s13 temp señor since my gauge was reading wrong.

Do I have to change both temp sensor?

5

No, keep the s13 temp sensor for the ecu. But replace the sender with an s14 one. What bov are you using?

6

Running hks ssqv. Is the sending one the one with clip that holds sensor or is it the one that you plug in a slot

7

2 pin sensor is for ecu
1 pin is the sendor

8

i have this same problem but mine a complete stock sr…and doesn’t seem to matter of the temperature…sometimes will hold an idle …sometimes will not just going up and down until eventually stalling out…i have checked for boost leaks…so i have no idea…

9

^ you try cleaning your iacv? I’m gonna give that shot next weekend and see how that turns out.

10

Little update- Still have the problem but now when it hits 75. So i replaced the s13 temps sensor with my old s14 temp sensor. Cleaned the IACV(was mint inside) Fixed all the boost leaks. I can drive it around for good 5-10mins and come out of gear with out the idle dropping. But once i get the 75 mark. Car wants to die when i pull it out of gear. Anyone got any ideas?

11

It sounds like the tune to me. The ecu is adding fuel at cold start once it is up to temp its leaning out on you on the base map. Is the tune made for your exact set up?

12

Yea it was tuned when I bought it. Only thing was motor was in s13 when it was tuned now it’s in a s14. Btw I’m not running o2 since previous owner told me I don’t need one for this setup.

13

Tune related

14

No 02? No narrow band makes sense but you need a wide band to make corrections to the base map. Its the tune and no 02 isn’t helping at all. It runs close loop on cold start, 02 not making adjustments. Then your ecu has no idea what to do once its up to temp and looking for an 02 signal. I could always be wrong but thats my throughts.

15

I’m using wideband to right now. My afr is close to 14.7 and sometimes bit rich/lean. I’ll start with a new o2 and go from there .

Thanks guys

16

Did the wideband come with the set up and is it wired into the ecu? Dont bother with a narrow band the wideband is what you want the ecu to read.

17

No it’s not wired to ecu . It’s aem wideband

18

Seems to me like your lack of 02 sensor is your problem.

19

Thats the problem for sure. Wire it in and see what happenes before you go get a tune. If it was running off a narrow band before you will need to change the setting on the ecu to read a wideband singal but once thats done you should be good to go.

20

Was it not stated above from a well respected tuner that this problem is tune related?