Revs go up and stay for seconds before dropping

[Bardia]

Hello members

Sorry if I'm asking a question that was asked before or smth but I couldn't really find a solution to it that tailored to my issue.

I bought a '14 FR-S back in January 2019, took it in for Throttle Body cleaning and Fuel Injection cleaning service in Late November. After the service, every time I come to a stop and press the clutch in, the revs go up and stay between 2K-3K for like 2 seconds before dropping, the car also tends to hold the gas for me when I drive as it keeps revving when I let go of the throttle. Legit makes my manual feel like an unpredictable auto. Car is completely stock too!!

Anyone have any solutions to this or can suggest some solutions ? I am about to call and grill Don Valley Toyota

UPDATE:
Disconnected the battery for 30 minutes, let the car relearn and the problem went away. A special Thank you to all those involved in this thread.

[j_ros94]

Mine also does this im here to see whats going on too.

Sent from my SM-G960W using Tapatalk

[Bardia]

Originally Posted by j_ros94

Mine also does this im here to see whats going on too.

Sent from my SM-G960W using Tapatalk

Did the dealer do the same service for yours too ?

[j_ros94]

Originally Posted by Bardia

Did the dealer do the same service for yours too ?

No mine happened on its own but mine is boosted.
Mine happens in first gear with the clutch in. If im behind someone on a stop sign i dont put it in neutral i just stay in first gear but the rpms stay at 1.5-2k before it drops.

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[Bardia]

Originally Posted by j_ros94

No mine happened on its own but mine is boosted.
Mine happens in first gear with the clutch in. If im behind someone on a stop sign i dont put it in neutral i just stay in first gear but the rpms stay at 1.5-2k before it drops.

Sent from my SM-G960W using Tapatalk

I am gonna go out on a limp and say maybe, just maybe, hypothetically my throttle body is like kinda not closing when I let off the gas, hopefully not the case.

[ActionMaxon]

My advice is to grab a scanner and do a code clear. You may not have codes but doing a clear will reset adaptive values. If you don't have one disconnect the battery and reconnect after 30 minutes.

My thought is that your engine computer is running on old adaptive values from before throttle body cleaning and is having trouble re learning.

With less carbon build-up there would be more airflow at any given percentage of throttle opening which would make sense given your symptoms. More air, more rpm.

The shop should have done this when they did the work but maybe didn't.

[humfrz]

I reckon the linkage to the carburetor is binding. Oil up the pivot points.

Oh wait, where am I -

Oh, OK, here I am. -

I'd suggest you go with ol @ActionMaxon 's suggestion.


humfrz

[Jordanwolf]

It's definitely an overflow blinker fluid reservoir. Disconnect the exhaust, open your trunk and drain blinker fluid.

[steve99]

Check for intake leaks ie check all intake hoses especially ones under intake manifold.


Remove intake hose, with ignition on but engine stopped have a mate press accelerator to floor then release check the throttle butrerfly moves freely full range



Disconnect battery for 30 minutes reconnect, start car let it idle with no throttle input for at least 2 minutes. Check again for fault

[humfrz]

Originally Posted by Jordanwolf

It's definitely an overflow blinker fluid reservoir. Disconnect the exhaust, open your trunk and drain blinker fluid.

This is a serious thread - behave yourself -
















humfrz

[Bardia]

Originally Posted by ActionMaxon

My advice is to grab a scanner and do a code clear. You may not have codes but doing a clear will reset adaptive values. If you don't have one disconnect the battery and reconnect after 30 minutes.

My thought is that your engine computer is running on old adaptive values from before throttle body cleaning and is having trouble re learning.

With less carbon build-up there would be more airflow at any given percentage of throttle opening which would make sense given your symptoms. More air, more rpm.

The shop should have done this when they did the work but maybe didn't.

Thank you for your solution; I will try it within this week and report back on the same thread.

[Bardia]

Originally Posted by Jordanwolf

It's definitely an overflow blinker fluid reservoir. Disconnect the exhaust, open your trunk and drain blinker fluid.

Do I need to change my muffler bearings while I am at it ? Also my 2nd transmission decoupled supreme is throwing check brakes codes 😂😂😂
It is actually funny though, feels like an auto

[Bardia]

[QUOTE=steve99;3281813]Check for intake leaks ie check all intake hoses especially ones under intake manifold.


Remove intake hose, with ignition on but engine stopped have a mate press accelerator to floor then release check the throttle butrerfly moves freely full range



Disconnect battery for 30 minutes reconnect, start car let it idle with no throttle input for at least 2 minutes. Check again for fault[/QUOTE

Hmm thank you, Imma follow yours and actionmaxtons solution, hopefully it all comes out fine. Good part is that it is in storage for the next two months.

[Jordanwolf]

[quote=Bardia;3281871]

Originally Posted by steve99

Check for intake leaks ie check all intake hoses especially ones under intake manifold.


Remove intake hose, with ignition on but engine stopped have a mate press accelerator to floor then release check the throttle butrerfly moves freely full range



Disconnect battery for 30 minutes reconnect, start car let it idle with no throttle input for at least 2 minutes. Check again for fault[/QUOTE

Hmm thank you, Imma follow yours and actionmaxtons solution, hopefully it all comes out fine. Good part is that it is in storage for the next two months.

Are you making it a track/race car, or just a hobby car?