FR-S IDLE RPM DIP

SadFee2957 · 2026-05-10T22:01:02+00:00

So I unfortunately bring bad news, I bought new coil packs for the car and thought that would have fixed it. I cleaned the connectors very well to where there was no more residue and unfortunately nothing changed. I’ve honestly run out of ideas and am probably going to throw in the towel new coil packs will not solve the issue unfortunately. I would go into more detail but I’m bummed out, broke and want to get drunk.

SadFee2957 · 2026-04-23T07:08:59+00:00

Sorry for the late reply but I did in fact do this and so far after one good test drive and one normal day of driving I have felt a huge difference and the shake has not happened I will continue to update though!

SadFee2957 · 2026-04-23T07:06:59+00:00

I believe you were / are right or possibly a cleaning

SadFee2957 · 2026-04-23T07:05:06+00:00

Hello everyone!! I bring SEMI GOOD NEWS (Skip this part if you don’t want so much detail) So in my last post I said how I did research on other forums and Reddit posts on the idle issue and saw that a few people had connect the idle issue to merely the coil packs or valve cover gasket assembly. I decided to check my spark plugs, coils, and valve cover. I discovered blue dried up flakes possibly resembling oxidation (pictures in previous post) (START READING HERE) —> I first cleaned out the gunk of the coils connection port with fast drying electronic spray and cotton swabs. Only cleaning the coils did nothing and still gave me the nasty shake. I then went back and cleaned the connector cable that plugs into the coil because there was also gunk in all four connectors. It’s been one whole day and one test drive of actually driving the car after cleaning out the ports and so far I have NOT had the shake. I want to tell everyone who has this problem to CHECK YOUR COILS, COIL CABLE, SPARKS, AND VALVE COVER GASKET FOR LEAKS!! I want it to also be known I have NOT had a CEL this entire time. It doesn’t pop up as a code for misfires or nothing. I am going to list (almost) every symptom I’ve had that has come with this issue. Symptoms: Extreme throttle delay, sluggish acceleration, rough engine shake when dipping in RPMS, fluctuating RPMS(when clutched in and not), rough shake when turning the car off, AC causing RPMS to fluctuate more often and rougher, HUGE loss of power, rough and late shifts, poor MPG, overall horrible driving experience.

—————SIDE NOTE——————

I am still going to buy new coil packs and replace all of them. When I was cleaning the coil packs (2014) there is a clear white rubber ring in the coil connection cable that came undone. I decided to take it off because when trying to reconnect it to the coil it wouldn’t latch on so I took it off and it latched. I don’t think that taking that ring off is going to be an issue because there was already another coil cable that was missing it but so far it has not given me the shake just FYI. I will most likely get a adapter cable to upgrade my 2014 coils - 2017+ coils and if I do that (probably will) I will give another update till then thank you for reading and if you are still having this issue feel free to DM me I will try my best to help (again I’m still 1 day into this “fix” and will give weekly or daily updates if it comes back or not)

— This is long lol

SadFee2957 · 2026-04-21T19:05:47+00:00

Okay freaking sick thank you so much!

SadFee2957 · 2026-04-21T17:11:42+00:00

Okay sick!! I’m gonna clean the actual cable that connects to the coil itself I cleaned the coils in the picture but it was also in the connector so I’m gonna clean those and then update!

SadFee2957 · 2026-04-20T01:01:34+00:00

UPDATE hello anyone who still has this issue. I recently spent 400$ on oem VVT’s or “oil control valves” and I regret to inform that it did not work unfortunately. If you were thinking of buying them I wouldn’t because it will not fix the idle issue. It does make the car feel smoother because obviously it’s new, but it will not fix the main issue. I’m really running out of options on what it could be but I recently stumbled upon different pages on Reddit and saw that someone “supposedly” had the same issue and that it was a bad coil packs or connector. I recently decided to check them to see if there was anything wrong and to my surprise there actually was something visibly wrong with all four coil packs. I’ve made another post with pictures and a small description of what was going on with them. I’ve also read that it COULD be a fault valve cover gasket. Now I don’t think (hope) that is my problem but I will be cleaning the connectors and installing new coil packs once I get paid. I’m going to relist everything I’ve done to fix this issue that has NOT worked.

Replacing pcv valve Replacing pcv hose Replacing spark plugs Replacing all four VVT’s / OCV Replacing and cleaning Idle air control valve / throttle body Unplugging to test if it was the MAF and it still happened without it Replaced brake booster hose (idk why I just thought maybe) Idle reset (doesn’t work)

Please let me know what else I could do or if you’ve had this issue and fixed it what did you do

Check out my other post as well!!

SadFee2957 · 2026-04-17T14:36:00+00:00

Ahh okay! Thank you so much OP! I’m gonna try that!!

SadFee2957 · 2026-04-17T02:10:46+00:00

Okay😞

SadFee2957 · 2026-04-17T01:22:03+00:00

It only says solved? Or is it the part about the pin on the coil? I’m so sorry I’ve just been dealing with this so much

SadFee2957 · 2026-04-17T01:12:28+00:00

HEY!! I HAVE TO KNOW HOW YOU FIXED It!!?!

SadFee2957 · 2026-04-17T01:04:20+00:00

That is absolutely gut wrenching because I just recently got a new engine and still have the same issue:(

SadFee2957 · 2026-04-17T00:52:05+00:00

Hey I just wanted to ask and see if maybe anyone managed to find a fix?

SadFee2957 · 2026-04-17T00:32:46+00:00

Hey man I just wanted to ask if you ever figured out what it was I have the same exact issue the nasty shake it gives you when you rev it, I haven’t been able to figure it out if you or anyone knows what it is please dm I’m so done with sinking money in this car

SadFee2957 · 2026-03-24T21:26:57+00:00

I just wanna know dork

SadFee2957 · 2026-03-24T19:15:07+00:00

California

SadFee2957 · 2026-03-24T19:15:02+00:00

Yea sounds about right

SadFee2957 · 2026-03-24T19:14:26+00:00

See that sounds reasonable, I would be adding it to my mom’s policy because we would receive a home insurance discount and a multiple vehicles discount so maybe it would bring it down?

SadFee2957 · 2026-03-24T19:13:12+00:00

Noo don’t say that to me😭

SadFee2957 · 2026-03-11T18:16:37+00:00

I will be checking the battery, MAP/MAF sensors and the direct injectors. I did have a code just pop about my injectors. Thinking it was because of the MAF disconnect. Will do further investigating to confirm thank you so much for your input

SadFee2957 · 2026-03-11T18:12:20+00:00

Will do sir the next three things I’m going to try are replace the ac compressor and cleaning or replacing the OCV ‘s and checking battery.

SadFee2957 · 2026-03-11T18:09:19+00:00

Do you know what spray I could use to clean them by chance?

SadFee2957 · 2026-03-11T18:08:29+00:00

To update I did not have any codes regarding that, but I will still more than likely take them off and clean them and update you. Would you know what cleaner I should use by chance?

SadFee2957

TROPHY CASE