My 2001 Passat’s heater went out recently. I had the coolant and thermostat changed in May 2007 and the blower and a/c work fine. When I turned the temperature **** to heat luke-warm air blows out. Does anyone have any ideas on what is causing no heat or has anyone experienced this with their VW?

 

Yeah, I have the same crap now for the second winter. Some stuff you can think about: coolant level, a kinked hose from other service/repair, blocked heater core (1 in 100 chance). I have posts out to see if there are any air or electrical valves or dampers that I'm unaware of. (No replies yet) I have had the system back flushed and that helped intermittently. VW wants to replace the core to the tune of $1300. I think I'm gonna drain down the coolant, and run the engine to temp; while SLOWLY refilling the system, to see if maybe there is an air lock in the core. Also, I'll be probing around with my inferred thermometer to see if both inlet and outlet side core hoses are different or about equal temps. I'll let you know if I find something. Keep your feelers out about the valves dampers stuff and maybe we'll both not have frozen feet the remainder of the winter.

 

Same problem here, VW said that my heat is normal....I guess they didn't mean for this car to end up in a state that has cold winters. Any help on a fix would be appreciated.

 

I have a 04 Jetta TDI. I have a circulating block heater that came from the dealer. I have a real hard time getting engine temp up to operating temp while driving in the city. When out on the highway at 100kph the temp comes up to operating levels. I think these engines need tobe worked to make heat. I used a infared temp gun on some hoses to see if the thermostat is releasing coolant before hitting 170f. It appears that it is so I am changing the thermostat shortly. I still am not optomistic that the engine will warm up quickly without makeing it "work for it" though. I have read on other forums of the same issue.
It appears to be nature of the design.

 

Today I worked on this issuemore. I have got heat! Here's what I did. I took the heater hoses off the core. Since the engine was up to temp, I was expecting lots of fluid to escape under good pressure. There was little pressure and little volume. I took unregulated air pressure (175 lbs) off the compressor and blew the snot out of the core. VERY little junk came out. I did both tubes. Nothing.Took it apart again. On the drivers side there is a fitting at the rear of the engine, it goes from rubber hose to a plastic 90 ell to the metal tubing that goes into the bulkhead at the oil filter. Blew the snot out of that. Nothing. Ran the car with both heater hoses disconnected. Now, I should have been pumping coolant like crazy. Nothing. Blew thru the hoses until coolant gushed out. Put it all back together and it works. The blockage was somewhere in the block, NOT in the core. After that I could blow thru the system by mouth. Topped off the system and it works great. As I test drove, I noted at speed, the air temp at the vents was @150 deg. F. When I stopped I noted the temp rolled off to @120 deg. F. (Used an IR thermometer). Now I wonder if the expansion tank cap is not operating at the proper pressure. I don't have the spec. for it and I may just replace it as a matter of course. I opened the cap at full operating temp. and got very little hiss, making me think the closed system pressure might be too low.

 

I have same problem , the hot water not coming from engine , does the 2002 Passat have a control valve ? to open and close the hot water?
thanks