sik96ls400

I just got a tuneup: plugs, wires, fuel filter, air filter, caps, rotors, coolant temperature sensor, pcv valve. But I have a couple questions:

1. When I'm at a light, or just idling, car idles a lil under .5 RPMS. I think thats pretty low..Is that normal?

2. I still don't get 25 miles to the gallon on the highway, any suggestions??


This is not really in regards to the tuneup, but
1. when I have the temperature at 85, it doesnt blow real HOT!! (its about 28 degrees in ny)
2. My check engine light came on. I got a code for 1 bad cat. Where could I get them cheap??

ryanSC300lover

iTrader: (1)

95LS400--Did all the tune up as you did, my idle is a bit higher than that.

I get 25mpg and have hit 26.5 few times. Depends on how you drive. Depends on the gas, and many other factors.

Here it has been 10 and 15 below 0. I run the heater at 85 degree full fan speed or HOT at half fan speed. Both are INCREDIBLY hot.

PureDrifter

iTrader: (10)

1-flush the coolant, you have a bubble. if not, then the heat actuator is gone. easy fix either way.
2-clear the code, if it comes back quickly then you'll need a new Cat.

also adjust the idle speed to about 650ish at a "hot" idle when in park with the AC Off.

sik96ls400

1. the coolant was flushed when i did the timing belt and water pump about 2000 miles ago. so where could i buy that heat actuator??

2. after the code was read, i've driven about 60 miles. so should I still wait until it comes on again?

3. and how do you adjust the idle speed? i dont do any of the work on this car

91 LS400

clean throttle body
http://www.mobiloil.com/USA-English/...le_Bodies.aspx

if u had a misfire code P0300 to p0308 u might need a CAT
http://my.is/forums/f114/lexus-is300...-cycle-298769/

LiCelsior

iTrader: (32)

to adjust the idle speed, all u do is follow these instructions to adjust the TPS sensor. http://www.lexls.com/tutorials/EFI/tps.html it should be the same idea right PD?

91 LS400

U Know why u have 2 turn that screw? dirty TB or ISC
then u dont have to set TPS
U dont set idle with the tps....HAHA
U set the tps so it knows your @ closed throttle & it ohms

Now use your ohmmeter to check for continuity between terminals IDL and E2 with the 0.40mm thickness gauge still inserted between the throttle stop screw and lever. There should be continuity. U have the tps unpluged in for this!

91 LS400

I Just Checked nodata haha alldata
Idle speed is computer controlled and is not adjustable. If idle related problems exist, refer to COMPUTERS AND CONTROL SYSTEMS ok
PURPOSE
The idle speed control valve (ISC) maintains proper idle speed under various engine demand periods. The ECU directly controls operation of the ISC valve.

PURPOSE
The throttle position sensor detects throttle angle and idle position of the throttle plate. A sub-throttle position sensor is used for traction control. Both sensors will set a diagnostic trouble code (DTC) if a malfunction occurs.

LOCATION
The sensors are mounted on the throttle body.

CONSTRUCTION
Each sensor contains a potentiometer and an idle switch.

OPERATION
Whenever the throttle is opened, a varied resistance signal is reported to the ECU. When the throttle is returned to the idle position, the idle switch portion of the sensor is closed.

LOCATION
Mounted to the front of the air intake chamber.

CONSTRUCTION
The unit consists of a 4-winding stepper motor and a variable air passage.

OPERATION
By alternating signals to the individual coils the ECU is able to pull the valve open and closed. The shaft of the stepper motor allows for 125 individual positions of the valve.

PureDrifter

iTrader: (10)

pretty sure it's wrong, try the method from the 1st gen and adjust it.

also, i meant to say that you need to BLEED the coolant, not flush it, when you did the coolant flush you probably didnt do it properly.

91 LS400

Thanks PD
need to adj mine @ 400 - 450 (1200-1300 cold)
I will take pics this time
Should have a custumer coming in soon that not even dealer or others can fix for high idle sometimes and they had it for a week! and control arm bush
@ the shop just set and go. no time to fine tune it! just as long as computer see idle SW u can adj.

Vander

Yeah your idle varies whether or not the A/C is on. Also it is very likely you have an air bubble in your coolant system as people have said above. I would bleed it then go from there.