Slow Coolant Leak

[3rd Expyowner123]

2018 Expedition with 97k miles, with ESP Premium Warranty, maintenance history includes can phasers done twice, thermostat, water pump and heater hoses replaced. Dealer has added dye, done pressure checks and cannot find leak coolant leak. Coolant reservoir goes from full to almost empty over six month period. Dealer is now offering to charge about $500 to perform compression check to see if there might be a head gasket leak. Engine does not overheat and runs well.
Seen post on turbo cooling lines leaking but seems mostly on gen 1 engines.
I have authorized dealer to do the compression test, and change spark plugs although work has not yet been performed. Anyone experience a head gasket failure? Any suggestions from the forum? Thanks!

 

[apex96]

2018 Expedition with 97k miles, with ESP Premium Warranty, maintenance history includes can phasers done twice, thermostat, water pump and heater hoses replaced. Dealer has added dye, done pressure checks and cannot find leak coolant leak. Coolant reservoir goes from full to almost empty over six month period. Dealer is now offering to charge about $500 to perform compression check to see if there might be a head gasket leak. Engine does not overheat and runs well.
Seen post on turbo cooling lines leaking but seems mostly on gen 1 engines.
I have authorized dealer to do the compression test, and change spark plugs although work has not yet been performed. Anyone experience a head gasket failure? Any suggestions from the forum? Thanks!

Mine has a similar issue. Honestly at this point I’m letting it ride. It’s healthy, makes great power and torque… it’s got. 85,000 on it and a custom tune that makes it feel phenomenal. Every few months I take a look at the coolant reservoir and note the level, top it up if it’s at the low mark when hot.

 

[SyndicateZ]

2018 Expedition with 97k miles, with ESP Premium Warranty, maintenance history includes can phasers done twice, thermostat, water pump and heater hoses replaced. Dealer has added dye, done pressure checks and cannot find leak coolant leak. Coolant reservoir goes from full to almost empty over six month period. Dealer is now offering to charge about $500 to perform compression check to see if there might be a head gasket leak. Engine does not overheat and runs well.
Seen post on turbo cooling lines leaking but seems mostly on gen 1 engines.
I have authorized dealer to do the compression test, and change spark plugs although work has not yet been performed. Anyone experience a head gasket failure? Any suggestions from the forum? Thanks!

Try bringing to a dealer that might hopefully have better experinced techs to look at? If they cant find anything either...Just keep adding coolant as needed (have the dealer do it so they have a recored of the amount of coolant refills u have had to do there to support your coolant leak and their incompetence in finding the leak) and keep extending your Ford Premiem ESP as it get close to expiring to ensure you are fully covered for when the expy decides to FINALLY tell you where she was leaking from. If she is driving normally, no power losss, no codes etc just keep on going and know that u have a fail safe in the esp.

 

[SyndicateZ]

2018 Expedition with 97k miles, with ESP Premium Warranty, maintenance history includes can phasers done twice, thermostat, water pump and heater hoses replaced. Dealer has added dye, done pressure checks and cannot find leak coolant leak. Coolant reservoir goes from full to almost empty over six month period. Dealer is now offering to charge about $500 to perform compression check to see if there might be a head gasket leak. Engine does not overheat and runs well.
Seen post on turbo cooling lines leaking but seems mostly on gen 1 engines.
I have authorized dealer to do the compression test, and change spark plugs although work has not yet been performed. Anyone experience a head gasket failure? Any suggestions from the forum? Thanks!

Id do the compression test on each cylinder tho. Could definitely be coolant intrusion in a cylinder. If all the cylinders pass then i guess that good! ...lol

 

[LegalBrief]

Why are they trying to charge you for a compression test, it’s part of normal diagnostics for a coolant leak.

 

[3rd Expyowner123]

Why are they trying to charge you for a compression test, it’s part of normal diagnostics for a coolant leak.

To protect their profits! If they find an issue, then they would submit to Ford ESP for coverage.

 

[SyndicateZ]

Why are they trying to charge you for a compression test, it’s part of normal diagnostics for a coolant leak.

My local Ford dealers want $200 just to do a Brake inspection

 

[Benztech]

Why are they trying to charge you for a compression test, it’s part of normal diagnostics for a coolant leak.

No, it's not part of normal diagnostics for a coolant leak. They should do a pressure test, but not a compression test. A compression test is significantly more labor, and not the best way to check for a failed cylinder to cooling system leak. A leak down test would be better for that.

 

[Fastcar]

Try bringing to a dealer that might hopefully have better experinced techs to look at? If they cant find anything either...Just keep adding coolant as needed (have the dealer do it so they have a recored of the amount of coolant refills u have had to do there to support your coolant leak and their incompetence in finding the leak) and keep extending your Ford Premiem ESP as it get close to expiring to ensure you are fully covered for when the expy decides to FINALLY tell you where she was leaking from. If she is driving normally, no power losss, no codes etc just keep on going and know that u have a fail safe in the esp.

Perhaps when it hand grenades they will be able to have on of the "tech's" diagnose the problem. This stuff drives me nuts!!

 

[Doug12345]

No, it's not part of normal diagnostics for a coolant leak. They should do a pressure test, but not a compression test. A compression test is significantly more labor, and not the best way to check for a failed cylinder to cooling system leak. A leak down test would be better for that.

Compression check is not that labor intensive. Just pull plugs and do it. Probably take 45 minutes max.

 

[Jerald Cook]

I had the exact same issue on my 2020. Very slow leak, no visible drips, etc. Turned out the driver's side turbo had a leak in the coolant tube.

 

[20EBXLT]

Besides what you already mentioned, check the heater core hoses. These apparently fail pretty often. I had a set fail at 60k on a 2020 expedition max xlt.
I did a video on this here on my 2020 that shows where you can usually see the leak and where its coming from. Seems the coolant tends to leak onto the top of the passenger side turbo and burn off thus never seeing it on the ground, but the coolant overflow tank slowly gets empty over time and you have to keep re-filling. Might be worth a check and possible cross off the list of possibilities. I included part numbers and such in the video description too.

That Puddle Under Your Expedition? Here's Exactly What's Wrong | DIY Fix Heater Hoses

Struggling with a coolant leak on your Ford Expedition with the 3.5 Ecoboost engine? In this video, we show how to diagnose and fix heater core hose leaks. F...

youtu.be

 

[Benztech]

Compression check is not that labor intensive. Just pull plugs and do it. Probably take 45 minutes max.

While I agree with your comment a dealer will certainly charge more than 3/4 of an hour for a compression check. It just isn't part of basic coolant diagnostics. Sure you can pay more to have it checked but I've never seen where it's sold up front as part of diagnostics. It's a hard sell to tell customers diagnostics will be several hours labor.

 

[3rd Expyowner123]

Well after three service visits, my dealer replaced jumper hose to thermostat HL3Z*8K576*A. Dealer said coolant was leaching through hose. The hose has been stressed a lot with 2 cam phaser replacements, thermostat replacement, and two water heater pump replacement over 6 years. Asked them to replace coolant reservoir cap too. Hopefully the leak is now history.