TurboDieselPoint
Veteran Member
Hi all,
As some of you might have seen in my previous thread, my car's original heater core coolant passages blocked up (cold air out of passenger side) and my core was replaced per VW's TSB. Days after getting my car back with the new core, I noticed there was still a lot of contamination in the cooling system (orange coolant and sediment) so I had the service department flush the system again.
The coolant is pink and relatively clean now. However, what is strange is that only after this second flush (not after the heater core replacement and initial flush), suddenly my car is unable to maintain the rock solid 206*F (Scangauge II) coolant temperature it always closely stuck to for the first 3 years and 31,000 miles I owned it. Now, coolant temperature bounces between 207*F and 213*F. Particularly, it loves to be between 209*F and 211*F, even when I am just cruising in light traffic at speeds less than 50 mph. Mid-regen at a steady 70 mph on flat ground (ambient temperature near freezing) gave me a max of 216*F, a temperature I have NEVER witnessed before from this car, even under the exact same conditions.
--The coolant is fresh and is a spot-on 50/50 mix (verified with refractometer).
--I attempted to burp any air from the cooling system by removing the reservoir cap and idling the car until it reached full operating temperature. This changed nothing.
What gives?
Aside from air getting into the system, the only thing I could think of is that the oil cooler, EGR cooler, or thermostat got clogged or screwed up from crud stirred up from this last flush, restricting coolant flow.
Any ideas?
Thanks!
As some of you might have seen in my previous thread, my car's original heater core coolant passages blocked up (cold air out of passenger side) and my core was replaced per VW's TSB. Days after getting my car back with the new core, I noticed there was still a lot of contamination in the cooling system (orange coolant and sediment) so I had the service department flush the system again.
The coolant is pink and relatively clean now. However, what is strange is that only after this second flush (not after the heater core replacement and initial flush), suddenly my car is unable to maintain the rock solid 206*F (Scangauge II) coolant temperature it always closely stuck to for the first 3 years and 31,000 miles I owned it. Now, coolant temperature bounces between 207*F and 213*F. Particularly, it loves to be between 209*F and 211*F, even when I am just cruising in light traffic at speeds less than 50 mph. Mid-regen at a steady 70 mph on flat ground (ambient temperature near freezing) gave me a max of 216*F, a temperature I have NEVER witnessed before from this car, even under the exact same conditions.
--The coolant is fresh and is a spot-on 50/50 mix (verified with refractometer).
--I attempted to burp any air from the cooling system by removing the reservoir cap and idling the car until it reached full operating temperature. This changed nothing.
What gives?
Aside from air getting into the system, the only thing I could think of is that the oil cooler, EGR cooler, or thermostat got clogged or screwed up from crud stirred up from this last flush, restricting coolant flow. Any ideas?
Thanks!
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