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Discussion Starter · #1 ·
So I recently purchased a 17 Focus ST 100% stock at 32,000 miles about 6 months ago. Since I got the car the vehicle is now stage 2+ and have gone stratified tuned. Something I’ve realized since I’ve owned the car is on warm starts the vehicle sometimes drops low in rpms and shutters. The rpms spike back up and is around normal idle rpm range. What I did realize about this is every time I get a new oil change it stops doing it for a bit. Once the oil gets ran through the motor a few times it starts back up again... However once the car is running and driving it drives amazing and let me tell you stratified knows what they are doing! Still trying to figure this out and if a oil catch can, oil cooler or a pcv plate kit will help.
 

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2013 Ford Focus ST1
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So I recently purchased a 17 Focus ST 100% stock at 32,000 miles about 6 months ago. Since I got the car the vehicle is now stage 2+ and have gone stratified tuned. Something I’ve realized since I’ve owned the car is on warm starts the vehicle sometimes drops low in rpms and shutters. The rpms spike back up and is around normal idle rpm range. What I did realize about this is every time I get a new oil change it stops doing it for a bit. Once the oil gets ran through the motor a few times it starts back up again... However once the car is running and driving it drives amazing and let me tell you stratified knows what they are doing! Still trying to figure this out and if a oil catch can, oil cooler or a pcv plate kit will help.
Check that the car has had all recalls done - in particular those related to the fuel tank/vapour purge valve and also engine wiring harness TSB (although that one may not apply to a late vehicle like yours).
 

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17 st here also. I and so many others have/ have had this problem but I've never heard it be related to anything oil. These cars idle rough in general. Would say definitely check spark plug gap, if you are tuned most times its recommended to run step colder plugs gapped to your tuners specifications. Injectors can be an issue- may have to get them cleaned (least likely if you are experiencing no other symptoms during normal or wot driving) lastly would say it can be from carbon build up on valves

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Discussion Starter · #6 ·
I checked and all the recalls have been done. Also I do have the correct gap with the colder plugs from Ford performance. No codes are getting thrown. Just weird and so many other people have the same issue. Maybe it’s just the nature of the beaST
 

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I checked and all the recalls have been done. Also I do have the correct gap with the colder plugs from Ford performance. No codes are getting thrown. Just weird and so many other people have the same issue. Maybe it’s just the nature of the beaST
How long have the plugs been in there? You said gapped properly, just want to verify you have them at .026.

Ford Performance recommended. 028, but that's too large. Stratified recommends. 026. If the plugs look toasted, you should replace and gap the new ones.
 

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How long have the plugs been in there? You said gapped properly, just want to verify you have them at .026.

Ford Performance recommended. 028, but that's too large. Stratified recommends. 026. If the plugs look toasted, you should replace and gap the new ones.
^ this
If it has been over 5k miles on those new plugs, I wouldn't at all be surprised if they need checked again already. My ST was incredibly hard on plugs and plug gap.

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