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Hard to start when engine is warm

Business6

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#1
So here's a curious problem I've had for a while but this only happens with one step colder plugs. I've used NGK and currently have the Brisk plugs installed.

Cold start is normal regardless of the plugs but if I drive around for a bit, get some heat into the engine and leave it sitting for less than maybe 45 minutes to an hour it stumbles on ignition and sometimes, like yesterday, can take three or more tries to start.

Battery was replaced less than 18 months ago, fuel injector service 2000 miles ago, regular oil changes. It had happened stock, aside from the plugs, and with tunes.

Through my research I found the suggestion of pressing the gas when starting it up as, if that works, it should indicate an issue with a fuel injector or the fuel pump or something along those lines. But, given the only constant has been the spark plugs would that not point towards the coil packs?

The plugs certainly aren't worth the strain on the ignition system if I can't find a solution but I'd obviously love to keep them for the sake of the tunes. Anyone else have this problem?

Oh and there's no aroma of fuel or anything like that, in case that question comes up.
 


OP
Business6

Business6

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Thread Starter #4
Do a compression test.

Seriously.
It doesn't run rough and there's zero loss of power. If anything it's running the best it ever has. I don't see why I would run a compression test unless you have some further insight to your suggestion.

I stumbled into those suggestions. I'm curious about the FPR but I'd need a shop to run any of the tests as I don't have the means to do it even without the prying eyes of property management
 


Rocketst

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#5
Compression tests can point to a lot of things but it'll give you a general idea of the health of the motor. Whenever I have hard to diagnose problems thats my first go to. You have a frp sensor as well and can be accessed through the accessport. Check it and shoot us back some numbers.
 


TyphoonFiST

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#6
Put stock plugs back in.....if problem goes away it was the plugs. If it doesn't then you know you may have any injector leaking down. The FRP/Fuel Rail Pressure sensor hardly has issues....its usually the FLP/ Fuel Low Pressure sensor. Ask me how I know. I spoke with a parts guy and Tech @ ferd and they both said the FLP sensor is given out like candy at your Grandmas house.
 


MagnetiseST

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#7
It doesn't run rough and there's zero loss of power. If anything it's running the best it ever has. I don't see why I would run a compression test unless you have some further insight to your suggestion.
My first fiesta lost a cylinder this way, it would hard start when hot for months. I did a compression test and it was low in cylinder 2, ran perfect though.
 


Hypergram

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#8
I have the exact same issue. Take the swap the plugs out and the issue goes away. IDK what the cause of it is tho. Had this issue staring at 11k miles, soon after I got the plugs.
 


OP
Business6

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Thread Starter #9
My first fiesta lost a cylinder this way, it would hard start when hot for months. I did a compression test and it was low in cylinder 2, ran perfect though.
But was that exclusively with one step colder plugs? Not saying the problem wouldn't be there otherwise but I've outlined specific conditions that cause this.

I have the exact same issue. Take the swap the plugs out and the issue goes away. IDK what the cause of it is tho. Had this issue staring at 11k miles, soon after I got the plugs.
Very strange.
 


PunkST

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#10
Do a compression test.

Seriously.
Not even. Its the shit tastic brisk plugs. Ran a set on my svtf and had tons of issues. Whats happening is an incomplete burn during a hot start and it floods a cylinder. Go back to a normal style plug. And the issue will go away.

Currently running 1 year old ngk step colder plugs with .025 gap with no problems.
 


MagnetiseST

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#11
Wait theyโ€™re brisk plugs? Lol take that trash out. I know theyโ€™re โ€œracingโ€ but theyโ€™re just not as good as NGKs.

Also if youโ€™re gonna have them out, do a compression test anyway for peace of mind.

And to clarify yes I had 1step colder plugs when my engine failed.


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Dpro

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#13
some how I fear a plug named Brisk thats the fucking catch phrase for a frickin Ice Tea. I would never put plugs in my car named Brisk. lol
Ya NGK or Nippon Denso come to the top of the list followed by Bosch and a few other names but Brisk? :ROFLMAO: fuck no.
 


TyphoonFiST

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some how I fear a plug named Brisk thats the fucking catch phrase for a frickin Ice Tea. I would never put plugs in my car named Brisk. lol
Ya NGK or Nippon Denso come to the top of the list followed by Bosch and a few other names but Brisk? [emoji23] fuck no.
There is a Gentleman who runs a very High Hp Fiesta ST i think its 600whp. He is on facebook I think. Good guys racing..he Runs Brisks. FYI.

Here is his Vid

View: https://youtu.be/UZzbarVkh1I


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Dpro

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#15
There is a Gentleman who runs a very High Hp Fiesta ST i think its 600whp. He is on facebook I think. Good guys racing..he Runs Brisks. FYI.

Here is his Vid

View: https://youtu.be/UZzbarVkh1I


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Thats great not me. thank you very much. Oh I should also add he shoots for the moon on his car and if he blows its no big deal he will build another. Some of us are not doing that and would rather run plugs we know have consistent long term reliability.

Thing is you can cite race cars all you want in the real world its different. Why do you think no one warranties parts for race cars? Because the manufacturers know the product is exposed to extremes and stuff breaks.

Oh and if your smart ass cannot get over the joke part of the Brisk name then you have lost your edge and should be banished from making smart ass comments. :ROFLMAO:
 


TyphoonFiST

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Thats great not me. thank you very much. Oh I should also add he shoots for the moon on his car and if he blows its no big deal he will build another. Some of us are not doing that and would rather run plugs we know have consistent long term reliability.

Thing is you can cite race cars all you want in the real world its different. Why do you think no one warranties parts for race cars? Because the manufacturers know the product is exposed to extremes and stuff breaks.

Oh and if your smart ass cannot get over the joke part of the Brisk name then you have lost your edge and should be banished from making smart ass comments. [emoji23]
Last time I checked this America Jack...I am entitled to my opinion as are you. This is a clear statement that Brisk are not of poor quality at all. They ran stock block and trans also. This shows that our stout little FiSTs can handle quite a bit AND IF YOU CANT STAND FACTS I am sorry that you cant comprehend any of this and may have an extra Chromosome in your genealogy. In the end you should just shut your pie hole before someone or even you..... yourself puts a foot in it. Quit muddling up his thread also with your Smegma.



 


OP
Business6

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Thread Starter #17
As stated in the OP the problem has been the same with NGK or Brisk. I've never had the problem once with stock plugs
 


TyphoonFiST

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#18
As stated in the OP the problem has been the same with NGK or Brisk. I've never had the problem once with stock plugs
I didn't either....on the stock turbsky. But with either NGK or Brisk it has always took a split second longer to start. But I have never had a total failure of either plug...I just changed them out to try others for fun as its cheap enough.
 


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