LS240_sx

i swapped a ls1 into my Nissan 240sx and the idle is high. The tps is at the right adjustment and to my knowledge I have no vacuum leaks. It has not been tuned yet and the motor has a lunatic 232/238 can in it. Would tuning it fix my idle problem? Or is this something that has to be addressed before. It idles fine however it won't drop below around 1200-1500 rpm

LS240_sx

Anyone? Please

G Atsma

You might post the tune here. There are many here who can read it and see if there is something that can be done to it if necessary.

LS240_sx

how do you even go about doing that?

wannafbody

iTrader: (2)

I'd think a lunatic cam might be a bit unstable.

LS240_sx

these are the specs

• 288
• Duration @ .050 (Int/Exh): 232/238
• Gross Valve Lift (Int/Exh): .599"/.601"
• LSA/ICL: 113/109
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 2400-7000

VandykeT/A

What intake and throttle body? Does idle hold steady at 1200? To find a vacuum leak let idle stabilize with the car in closed loop and run a scan tool under the hood and watch stfts while spraying starting fluid around the intake. If you find a leak the idle may not change much but fuel trims will shoot deep in the negatives. Sounds like a vacuum leak or the throttle blade is drilled or open to far and the tps is just reset for its new position. You have to be getting extra air from some where if the tps is at zero idling. The ecm is shooting for whatever idle is set at in the tune and it can't close the IAC enough to compensate.

LS240_sx

ok. The intake is a fast lsxr102 and the TB is a Holley 95mm

2xLS1

iTrader: (25)

It takes air to increase rpms. Find where the extra air is getting in.

VandykeT/A

it is a cable throttle body right? I would bet If you looked at IAC counts they're pegged. I had a professional products (I believe) on my stock intake once. The throttle screw was way off. If you don't have any vacuum leaks try adjusting it closed and do a tps reset. That throttle body may be adjusted out to far out of the box.

qweedqwag

Get it tuned GEEz.

Bspeck82

Try adjusting iac.

big hammer

Make sure the throttle is indeed closing 100%. Even if the cable is just tight it can cause a high idle