Rough cold idle

[Chickensandwich]

My PIU has gone from horrible “vibration” at idle, even worse with AC on. A plug and coil were replaced and now when I start the car,’it idles rough, but gets better when it warms up. The dealership advised me to dump 2 containers of chevron with Techron in it to help with the over all bad idle. As I said, the idle overall is better, but I’m the morning it’s pretty bad. The dealer said if it doesn’t smooth out, it could need an injector. That doesn’t sound right since it idles ok after it’s warm. I get an occasional check engine light with cylinder 2 misfiring (the same as where the coil and plug were replaced). Does this sound like an injector? I’m about 3/4 of the way thru the Techron tank full.

 

[lifer013]

I just picked mine (2015 w 101K miles) up from the auction today. I noticed the same thing. Rough idle and initial rev when cold but then when it warms up or gets up to 2K RPM it smoothes out. I was thinking it could be an injector but then I read some more about the water pump issue these tend to have. Have you read anything about that? I will be staying vigilant. If I hear anything helpful I will post here. Hope this gets solved for the both of us.

 

[Chickensandwich]

I just picked mine (2015 w 101K miles) up from the auction today. I noticed the same thing. Rough idle and initial rev when cold but then when it warms up or gets up to 2K RPM it smoothes out. I was thinking it could be an injector but then I read some more about the water pump issue these tend to have. Have you read anything about that? I will be staying vigilant. If I hear anything helpful I will post here. Hope this gets solved for the both of us.

The dealership said that if the two containers I’d Techron doesn’t clear it up, then the injector needs replacing. I asked about perhaps a thermostat issue but he said no, it’s injector based. I’m hoping the Techron cleans it up because I can’t afford a new injector

 

[peterk9]

I just picked mine (2015 w 101K miles) up from the auction today. I noticed the same thing. Rough idle and initial rev when cold but then when it warms up or gets up to 2K RPM it smoothes out. I was thinking it could be an injector but then I read some more about the water pump issue these tend to have. Have you read anything about that? I will be staying vigilant. If I hear anything helpful I will post here. Hope this gets solved for the both of us.

Welcome to the Forum.
I doubt it would be a water pump issue. You can check the oil on the dipstick to see if is a 'milky' colour and check your coolant tank level. It might be that the throttle body needs a good cleaning. Have you checked the spark plugs or know when they were replaced?

Peter

 

[Chickensandwich]

Welcome to the Forum.
I doubt it would be a water pump issue. You can check the oil on the dipstick to see if is a 'milky' colour and check your coolant tank level. It might be that the throttle body needs a good cleaning. Have you checked the spark plugs or know when they were replaced?

Peter

For me, fresh oil change and new plugs

 

[gapcomputer]

a new injector (Motorcraft) will cost you about $45, don't know how much you paid for the Techron, also if you have a noticeable ticking noise in the engine and goes away when it warm up, probably it is the injector.

Amazon.com: Fuel Injector : Automotive

Buy Fuel Injector: Fuel Injectors - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[Chickensandwich]

a new injector (Motorcraft) will cost you about $45, don't know how much you paid for the Techron, also if you have a noticeable ticking noise in the engine and goes away when it warm up, probably it is the injector.

Amazon.com: Fuel Injector : Automotive

Buy Fuel Injector: Fuel Injectors - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

I can’t install that crap, so $45 sounds great, but labor will be considerably higher. The car shimmys or “vibrates” at idle most of them, especially with the air on.

 

[VCFP153]

I can’t install that crap, so $45 sounds great, but labor will be considerably higher. The car shimmys or “vibrates” at idle most of them, especially with the air on.

If it's one of the three "front" injectors, it's fairly easy to replace. In fact, I would even swap all three at the same time.

 

[Chickensandwich]

If it's one of the three "front" injectors, it's fairly easy to replace. In fact, I would even swap all three at the same time.

It’s cylinder 2 I’m having the misfires on.