Tachometer RPM Dipping up/down ! IS350 Fsport
03-20-17, 04:51 PM
#1
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Tachometer RPM Dipping up/down ! IS350 Fsport
iHi guys, my IS350 F-sport RPM meter is go up and down while in Idle Park or D, i just noticed this morning, it doesn't do much, for example if the idle is at 1500 RPM the meter will go down to 1400 and back to 1500 to 1400 and back to 1500.
When the car is fully warmed up like just now got out from work, idle at 1000 it will go 1100 and back to 1000 and to 1100 and back to 1000.
I've never seen this before, what i can think of right now is = Dirty Throttle body, MAF Sensor, Air filter ? or leak exhaust ? heater on or off doesn't matter it still doing it.
RedLine and sasnuke where are you now i need you lol Justin Beiber .
When the car is fully warmed up like just now got out from work, idle at 1000 it will go 1100 and back to 1000 and to 1100 and back to 1000.
I've never seen this before, what i can think of right now is = Dirty Throttle body, MAF Sensor, Air filter ? or leak exhaust ? heater on or off doesn't matter it still doing it.
RedLine and sasnuke where are you now i need you lol Justin Beiber .
03-20-17, 08:01 PM
#3
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Any accessories on when it's happening?
Either front or rear defroster on?
If no to both questions above, does the battery look new or new-ish?
If yes, then clean the throttle body.
Either front or rear defroster on?
If no to both questions above, does the battery look new or new-ish?
If yes, then clean the throttle body.
03-21-17, 03:45 PM
#5
Instructor
Thread Starter
Yes 1 month old battery from Lexus Dealership, by the way 2-3 years old car need throttle body clean ? i noticed there is aftermarket air filter in the box . Does Gen2 air filter fit gen3 air filter box ? i still have the new gen2 air filter box from Lexus.
03-21-17, 03:46 PM
#6
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03-21-17, 05:54 PM
#7
When cold, in Park, I've noticed this behavior before but can't consistently reproduce. Does not fluctuate in Drive when idling though.
Best bet is to have your dealer look at it. It's still under warranty after all.
Best bet is to have your dealer look at it. It's still under warranty after all.
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03-21-17, 06:15 PM
#8
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Nothing on, doesn't matter on or off its still dip but little bit not too bad.
Yes 1 month old battery from Lexus Dealership, by the way 2-3 years old car need throttle body clean ? i noticed there is aftermarket air filter in the box . Does Gen2 air filter fit gen3 air filter box ? i still have the new gen2 air filter box from Lexus.
Yes 1 month old battery from Lexus Dealership, by the way 2-3 years old car need throttle body clean ? i noticed there is aftermarket air filter in the box . Does Gen2 air filter fit gen3 air filter box ? i still have the new gen2 air filter box from Lexus.
Keep in mind this is preventative maintenance to keep the vehicle running at optimum performance.
You could wait for the throttle body to get all nasty, then clean it...but why?!
Also, disconnecting the battery resets the ECU's learned value of the throttle body position, which adjusts over the years to the carbon buildup.
The ECU resets to the factory position of a clean throttle body...hence the erratic idle, as the carbon that is present now was not on the factory throttle body.
It can be so bad the vehicle won't even stay running...it will just stall.
With the proper cleaner, this is certainly a DIY item.
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Solara350 (03-21-17)
03-21-17, 06:55 PM
#9
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Thread Starter
As preventative maintenance it is recommended to clean the throttle body every 2 years or 48,000kms.
Keep in mind this is preventative maintenance to keep the vehicle running at optimum performance.
You could wait for the throttle body to get all nasty, then clean it...but why?!
Also, disconnecting the battery resets the ECU's learned value of the throttle body position, which adjusts over the years to the carbon buildup.
The ECU resets to the factory position of a clean throttle body...hence the erratic idle, as the carbon that is present now was not on the factory throttle body.
It can be so bad the vehicle won't even stay running...it will just stall.
With the proper cleaner, this is certainly a DIY item.
Keep in mind this is preventative maintenance to keep the vehicle running at optimum performance.
You could wait for the throttle body to get all nasty, then clean it...but why?!
Also, disconnecting the battery resets the ECU's learned value of the throttle body position, which adjusts over the years to the carbon buildup.
The ECU resets to the factory position of a clean throttle body...hence the erratic idle, as the carbon that is present now was not on the factory throttle body.
It can be so bad the vehicle won't even stay running...it will just stall.
With the proper cleaner, this is certainly a DIY item.
03-21-17, 08:24 PM
#10
Mine did this during warm weather. When it was cold out it would go up and down to the point of shaking at the light in D mode. It took almost 3 years for the fuel injectors to die. After they replaced the fuel injectors and exhaust manifold it stopped. I haven't seen the wild idling since!
03-22-17, 06:10 AM
#12
Instructor
Thread Starter
that what I'm talking about , the guy on YouTube with his new is350 Fsport doing review his rpm was dipping too, I don't know if this normal or not I guess I'll visit Mr Lexus dealer once. According to my experience the car drives fine and nothing suspicious .
03-22-17, 03:19 PM
#13
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Thread Starter
Mine did this during warm weather. When it was cold out it would go up and down to the point of shaking at the light in D mode. It took almost 3 years for the fuel injectors to die. After they replaced the fuel injectors and exhaust manifold it stopped. I haven't seen the wild idling since!
03-22-17, 04:45 PM
#14
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@cFoo...by any chance do you, or did you, buy gas in the States? Just curious. THe only times I've heard of injectors going on a Toyota/Lexus in the last decade was due to high ethanol fuel...from the USA.
03-22-17, 05:53 PM
#15
Instructor
Thread Starter
i was gonna ask you bro, i filled up gas at Esso station in Highway 7 lately because of free car wash with points, i remembered so well when i was test driving the car and checked everything and it was fine, when i went pickup the car we did swap out battery from my old car to the new car and i did not notice until i put gas at Esso station last week, i just checked my PCV valve this afternoon and i see oil around the pcv, gonna install an oil catch can clean up the throttle body and reset ECU again and see.