Cant get LTFT right

[droptopgst]

I have a 98 spyder with 18g and supporting mods. The LTFT is almost always at 12 on the pocket logger. I have tried everything on the afc from -5 range across the board to -25(and a CEL comes on when I go to either extreme). No matter where the afc is set the STFT bounces from -15 up to 24. I cant find out where the correct settings have been. I recently adjusted the AFPR to make sure it was set to 43psi. (with vac. line off) I have even disconnected the battery to reset the ecu. The timing is nice at WOT with a curve from 14-21. Anyone have any tips or suggestions

 

[v8killerr1]

how big are your injectors?

 

[droptopgst]

sorry,
Here is my set up: 98 gst spyder 20 psi
TDO5 18g ported, clipped,
34 mm w/g,
afc,
660 injectors
intake,
3"exhaust,
Type S bov,
Custom 2.5" icp,
man. bc,
afpr,
255fp,
npr intercooler,
ngk plugs and wires
Pocket logger

 

[Staytuned]

From what I have read your LTFT can not be adjusted, they are an estimated value based on your STFT values. If you get your STFT values in check it should bring your LTFT back with it. So start from scratch again by reseting your ECU and start by adjusting your correction % to make your STFT as close to 0 at idle then work your way up to your 2000 rpm setting and so on. This should bring things back to normal.

 

[espinelli]

In addition, before you get stable LTFT readings you'll have to warm up the car...cruise for 10mins @ 70-80mph ......let the care idle for an additional 10mins. Then compare your LTFT values. Keep in mind that if your venting your PCV and or your breather it will jack with your LTFT values. Hope that helps.

 

[droptopgst]

In addition, before you get stable LTFT readings you'll have to warm up the car...cruise for 10mins @ 70-80mph ......let the care idle for an additional 10mins. Then compare your LTFT values. Keep in mind that if your venting your PCV and or your breather it will jack with your LTFT values. Hope that helps.

na nothing is venting

as far at the STFTs goes, they bounce all over so much I cant get them to even stay close to 0. one min. they are 24 the next they are -15. The LTFT stays at 12 for the most part.

 

[Staytuned]

Thats sounds odd that they jump all over the place mine only move 2-3 % at any time.

 

[droptopgst]

yeah mine used to move from 3-9 or so. Now its moving like 30-40. No clue whats going on here.

 

[espinelli]

How about your FPR and fuel pump. If you install a fuel pump and don't upgrade your stock FPR that can cause some issues with your LTFT values. If the stock FPR is over run that will increase your fuel pressure and make it much harder to dial in your injectors.

Also, you need to make sure you fully warm up your car, cruise @ 70 for 10 minutes and let the car idle for 10 minutes...and then compare your mid and low LTFT's. Otherwise they will be all over the board.

Another factor maybe that your injectors are hosed or not matched. Make sure they are all the same.

 

[44pirate]

Do a boostleak test to make sure you have no vacumn leaks.