Likelihood of egr cooler and heater core failing at same time

Just before egr cooler noticibly failed I heard a change in behind dash water sounds. (Position and intensity increase) Made me think of heater core. Then got white smoke and antifreeze loss. Changed egr cooler and no more antifreeze loss or smoke. However, still have sloshing and no heat. What is likelihood of cooler and core failing at same time? Thinking air in system from cooler failing. Tried bleeding at heater core hose. Not much change. Both heater core hoses are hot. Any suggestions? Thanks in advance.

Sounds like you have air trapped. Passats are known for clogged cores but seems a good place to start since you drained and re-filled after your other repair. Try sliding the hoses back off the core exposing the bleed holes and run it

Thank you for your response. I will bleed it more. Get out as much air as possible. Thanks.

looking at the original post. Did you have heat loss before you started having issues with the egr cooler or was the heat working fine?
These cars do not like anything but G12 so if you added coolant was that what was originally used? When the cores get restricted people have had luck with flushing them as well with a calcium/lyme type cleaner. I've used CLR on older Ford Taurus's for people with good results

I am wondering if the frequency of coolant changes come to play. I've read that folks claim to only used g12 and still get clogged cores, but never mention how frequent the coolant was changed out.

My car has seen coolant changes about every 40,000 miles. G12, G12 ++, and the last two with G13. On the last change at 204k miles, I replaced the rear flange and could see it looks brand new inside cylinder head water jacket.
I am hoping my original EGR cooler and Heater core looks the same inside also.

I have no real science as to why, but I have seen a lot of B5 heater cores clog. Never any that I normally maintain, and know 100% for certain they ALWAYS had the proper coolant in them. So I feel like it is contamination.

BUT, I have had pretty good success flushing them out with a hose and a vinegar soaking procedure.

Straight store bought vinegar oilhammer or do you dilute it any?

Straight cheap stuff.... this isn't Rachael Ray

Just remove the hoses from the core, stick two ~foot long chunks on each port, angled UP, hold them that way with a bungee cord/coat hanger/clamp/wife/whatever, fill up one side until it levels off on the other side, so you know it is full. Then let it sit for 30 minutes or so.

Then take the garden hose, and flush it out both directions. If you get a bunch of brown muck out, you know you are clearing it out. May have to do this a couple times. But I have had success this way. Worth a shot, cheaper than taking the dash out and replacing the core.

Thanks to all for comments. I had a lengthy response ready to go and it got lost in the ether. Ugh! Anyway to answer questions. Did not notice loss of heat before the egr cooler started to go. I believe now as cooler was failing air was entering the system. Heard change in gurgling sounds and started thinking heater core. Then a couple of days later after a short trip, stopped and parked and had a plume of white smoke and consequent coolant loss. Read forums and narrowed to egr cooler or head gasket failure. Remembering gurus say head gasket is not a common failure item on these cars and no water in oil and no immediate reservoir pressurization (before getting hot), I ordered and replaced cooler. After trapped coolant burned off I had no smoke or coolant loss. Only vw g12 or higher (pink) coolant ever used in last five years since I have owned car. Has been drained and filled at least every two years. Bled system from core hose hole and at first did not think it did any good. Then next day started getting some heat. Now I will focus on bleeding air further. I also think heater core soak and flush would be in order. Engine is running great after its internal steam clean and all parameters are good on vcds scanning with coolant temps 93-96 degrees depending depending on load. Thanks again to everyone. Hope that covers everything. Any further questions please ask, I will be happy to respond.

just to follow up. bled system some more and now I have heat. obviously air entered with failure of egr cooler. thanks again.

highmileage said:

just to follow up. bled system some more and now I have heat. obviously air entered with failure of egr cooler. thanks again.

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The thing that makes me happiest about this response is you actually took the time to thank people that took the time to try and help out. Makes me still want to chime in every now and then

Thank you for your kind words.