[Bmontgomery94]

I have been having an issue where my engine rpm at idle will drop down to 400-500rpm sounding like it is about to stall before it recovers back to normal idle rpm. The dealer is telling me it is due to coolant intrusion in cylinders 2 and 3 causing them to misfire. They also said the only fix is a new engine. From my research, the STs, unlike some of the other fords, are not known for this issue. Has anyone else had experience with this?

 

[MrBen522]

I have been having an issue where my engine rpm at idle will drop down to 400-500rpm sounding like it is about to stall before it recovers back to normal idle rpm. The dealer is telling me it is due to coolant intrusion in cylinders 2 and 3 causing them to misfire. They also said the only fix is a new engine. From my research, the STs, unlike some of the other fords, are not known for this issue. Has anyone else had experience with this?

Get codes read. autozone will do it for free if you don't have access to a code reader. That could be a purge valve issue (see this post) If not, these engines can crack ringlands. (research LSPI) Once we can see the codes we can tell you more.

 

[Machspeed]

Yes, possible purge valve issue. Get yourself another opinion.

 

[sttwoton]

The ecoboost used in the ST are closed deck block, unlike the later ones used on other models, which were open deck, they were the ones that have the coolant intrusion problem, the closed deck blocks are really tough, it’s what the high end, big power engine builders use as a basis for the RS over here, because of their superior strength.

 

[noskyman]

First off are you losing or using coolant ? If no then that is not your problem. Tell us about your car and any mods you have.

 

[Bmontgomery94]

Thanks for the input, I didn’t think what they were telling me sounded right. I will ask some more questions. I’ve had no issues with losing coolant in the past. My ST if fully stock, no mods.

 

[Bmontgomery94]

Also I found this recall which sounds like it could be the issue. Bought the car used and all recalls say they have been completed. I’m also having some battery issues so I wonder if this could be related to the wiring? Or the KAM not being set properly after battery replacement?

https://static.nhtsa.gov/odi/rcl/2014/RCMN-14V495-5503.pdf

 

[ddfred]

The tech that did the splice repair; if your car was on the list and it was performed, may have done a crap job. Here is a PDF that outlines how to do it yourself, properly.

file:///C:/Users/13162/Downloads/TSBsplices122015%20(4).pdf

 

[Bmontgomery94]

So they gave me this picture to confirm that there is coolant in the cylinders. They said that they were getting misfire codes for cylinders 2 and 3. This still doesn’t sit right with me as I’ve never had this come up before and I’ve never been low on coolant. Is it normal to have a small amount of coolant get into the engine? Could the idle issues and misfire codes be related to the possible electrical ground issues? Should I get a second opinion on the engine?

 

[TurboGT]

While this is very uncommon, proof is in the pudding.

This would create misfires typically in the first minute of run time until the coolant is run out of the cylinders.

I don't think a second opinion is necessary

 

[Mzdrati]

If that is coolant- wouldn't it be true that significant amounts of water vapor would be visible coming out of the exhaust? Is that what is happening? If so- could this be a head gasket failure and not necessarily require a full engine replacement?

 

[STallion18]

Check the oil, if it is milkshake solution, then bearings could had been compromised. Full rebuild in order. If no sight of coolant in oil, head gasket compromised, must be replaced as soon as posible if just started. Head has to be resurfaced, a good used engine could be cheaper.

 

[beretta96]

If you have visual proof there is coolant in the cylinders but aren’t seeing any noticeable loss in the reservoir nor are you getting white, sweet smelling exhaust like @Mzdrati described then you’re fortunate to have caught it early and probably don’t need an engine rebuild.

That said, folks say it costs more to do a head gasket job than an engine swap. I said head GASKET job!!

I don’t know the cost difference between a head gasket swap and buying a new/used engine then paying for the labor to swap it.

Nevertheless, if you kept the oil clean and haven’t treated it like a prostitute, it may be worth it to you to pay for the head gasket swap?? Just giving you ideas brah! 👍

 

[Bmontgomery94]

So the dealer and another shop I talked to are telling me that there are problems with the way the engine block was manufactured so a head gasket job wouldn’t fix the issue. I believe they are referring to the open deck cooling system on other eco boost engines. My ST has 77.5k miles on it and I haven’t seen signs of coolant in the oil. Seems like it could be a good candidate for a head gasket job vs an engine swap. Is there a document I can reference to point them to the fact that the st does not have this open deck coolant system?

 

[junits15]

If they are saying there is a defect in the block they are more than likely correct. The open deck issue with RS's was solved by switching the head gasket, not by swapping the motor. So even if they were confused about what kind of motor it was they still wouldn't push towards a new motor as the fix for the open deck issue was just to R&R the gasket.

Ask for details on the failure, without info its not safe to assume anything about what's going on.

 

[Skykri]

Here ya go

Focus ST 2.0 freshly stripped
Vs

2.0 that likes to puke coolant

Sounds like a case of a stealership being actively ignorant or TRYING to screw you out of money.
In any case. You need more info from them.

 

[TurboGT]

If they are saying there is a defect in the block they are more than likely correct. The open deck issue with RS's was solved by switching the head gasket, not by swapping the motor. So even if they were confused about what kind of motor it was they still wouldn't push towards a new motor as the fix for the open deck issue was just to R&R the gasket.

Ask for details on the failure, without info its not safe to assume anything about what's going on.

The fix for the 1.6 and twinscroll 2.0 open deck block was a full engine replacement. Either way they're confused on what they're working on.

I don't have a document describing this for proof.

O.p, You need to stop trying to force their hand, though. The one and done repair for your car is an engine replacement, period. If you force them to do the head gasket, what happens when the cylinder head bolts pull the threads out? Because this is what happens to all aluminum engines if they've gotten hot (don't tell me it hasn't. Neither you nor I know that).

You also run into the risk of deck and head warpage. HG failure isn't common on these engines. So why did it happen in the first place? Did the gasket lose squeeze due to a warp scenario?

My point is, you're going to have a ton of money and extra time in tearing it down, finding bigger issues. Paying labor for teardown and the inevitable engine replacement, over just slapping an engine in and moving on.

If you chose to tackle this by yourself, then sure. Do a HG. The only thing you're gambling is your own time at that point.

 

[junits15]

The fix for the 1.6 and twinscroll 2.0 open deck block was a full engine replacement. Either way they're confused on what they're working on.

I don't have a document describing this for proof.

O.p, You need to stop trying to force their hand, though. The one and done repair for your car is an engine replacement, period. If you force them to do the head gasket, what happens when the cylinder head bolts pull the threads out? Because this is what happens to all aluminum engines if they've gotten hot (don't tell me it hasn't. Neither you nor I know that).

You also run into the risk of deck and head warpage. HG failure isn't common on these engines. So why did it happen in the first place? Did the gasket lose squeeze due to a warp scenario?

My point is, you're going to have a ton of money and extra time in tearing it down, finding bigger issues. Paying labor for teardown and the inevitable engine replacement, over just slapping an engine in and moving on.

If you chose to tackle this by yourself, then sure. Do a HG. The only thing you're gambling is your own time at that point.

Good catch, I forgot about the twinscroll motor that makes more sense.