Low Idle/DTC Code P0505 solved
06-18-06, 08:08 PM
#1
Pole Position
Thread Starter
Low Idle/DTC Code P0505 solved
Hi, Guys.
I have solved the problem i was having with the low idle (400 rpm) and the engine check, vsc and vsc off icons lit ,with DTC code P0505, on my 98 GS400. The first thing i did was to reset the ecu (via fuse), still had the lights. Following day while driving i noticed that the icons were no longer lit, but the low idle was still present. Next day i cleaned the throttle boby, on the advice of a lexus mechanic, these are the steps necessary to clean the throttle body. Key factor is that the ignition key must be in the acc position. Rotate the the spring spindle to open and keep open the butterfly, clean inside of the air shaft front and aft of the butterfly and the butterfly rim itself. You will hear the fuel pump going, this is not a problem. Put every thing back together and then removed the ecu fuse for atleast 20 minutes (ie reset ecu). Start the car, the engine will rev very high and maintain high revs 1100-1300 rpm. let it run for about 2 minutes, then drive the car aroung the block, revs will gradually return to normal factory settings, mine idles now at 700 rpm (spot on) No more engine check, vsc and vsc off lights. Total cost of my fix was $2.99 for the can of STP throttle body cleaner (not $1400 as suggested by the lexus dealer for throttle body replacement CKIM's previous posts convinced me that replaceing the throttle body would not solve the problem).I sincerly hope this solves your problems with this issue. BTW throttle body cleaning should be a regular part of vehicle maintanance. (I did not know this) This was my first cleaning in 121 thousand miles of using 93/94 octane gas.
Hopefully it will work for you too.
Clive.
I have solved the problem i was having with the low idle (400 rpm) and the engine check, vsc and vsc off icons lit ,with DTC code P0505, on my 98 GS400. The first thing i did was to reset the ecu (via fuse), still had the lights. Following day while driving i noticed that the icons were no longer lit, but the low idle was still present. Next day i cleaned the throttle boby, on the advice of a lexus mechanic, these are the steps necessary to clean the throttle body. Key factor is that the ignition key must be in the acc position. Rotate the the spring spindle to open and keep open the butterfly, clean inside of the air shaft front and aft of the butterfly and the butterfly rim itself. You will hear the fuel pump going, this is not a problem. Put every thing back together and then removed the ecu fuse for atleast 20 minutes (ie reset ecu). Start the car, the engine will rev very high and maintain high revs 1100-1300 rpm. let it run for about 2 minutes, then drive the car aroung the block, revs will gradually return to normal factory settings, mine idles now at 700 rpm (spot on) No more engine check, vsc and vsc off lights. Total cost of my fix was $2.99 for the can of STP throttle body cleaner (not $1400 as suggested by the lexus dealer for throttle body replacement CKIM's previous posts convinced me that replaceing the throttle body would not solve the problem).I sincerly hope this solves your problems with this issue. BTW throttle body cleaning should be a regular part of vehicle maintanance. (I did not know this) This was my first cleaning in 121 thousand miles of using 93/94 octane gas.
Hopefully it will work for you too.
Clive.
The following users liked this post:
Amish (08-21-18)
06-19-06, 05:45 AM
#2
Glad it all worked out for you Clive. 
The stealership charges $1100 for a new TB 
I just cleaned my TB yesterday, and to my suprise it was dirty, but not filthy I used some TB cleaner and a rag, and got the dirt out. I reset the ECU and the car actually idles higher than before. Previously, it idled at 650rpm in drive. Now, the car idles at 850rpm 
The car takes off like a banshee now and feels so much more quicker off the line.
The stealership charges $1100 for a new TB I just cleaned my TB yesterday, and to my suprise it was dirty, but not filthy I used some TB cleaner and a rag, and got the dirt out. I reset the ECU and the car actually idles higher than before. Previously, it idled at 650rpm in drive. Now, the car idles at 850rpm The car takes off like a banshee now and feels so much more quicker off the line.
06-19-06, 06:01 AM
#3
Lead Lap
Good job man. I just posted a thread about doing this last week, made a big difference on my car. With 90k it was really dirty. The $2.99 STP cleaner saves the day again.
Thread
Thread Starter
Forum
Replies
Last Post
