Hey, you have MANY different problems here; that can be multiple issues and not just related to the cooling system.
1. brakes hissing: a common problem, is the plastic hose that connects to the brake booster will crack and cause idle issues a well. Check that and replace; if needed, that is a safety issue and could cause a accident, from poor performing brakes. Your brake booster; could also have a leak but most of the time, the hose is bad. Most likely Volkswagen part # 1J0612041AB : be sure to order with your VIN # to get the correct part.
1J0612041AB - Brake Vacuum Pipe With Check Valve - Hard vacuum pipe that goes to brake booster, comes with check valve
Hard vacuum pipe that goes to brake booster, comes with check valve
This vacuum pipe is located on the brake booster and connects to the F-hose on the left side of the intake manifold. A crack or break in this line can cause major vacuum problems and could possibly leave you stranded.
https://www.google.com/search?q=1J0...rome..69i57&sourceid=chrome&es_sm=91&ie=UTF-8
2. Check engine light; you won't know, what the reason for the light is coming on until you scan it for trouble codes. Once you get the codes; please, post them up and we will do our best to help. A generic obd II scanner; is ok but a VW specific scanner, like VCDS or a cheap volkswagen scan tool off of amazon.com is recommended (basic one like vs450 etc.).
3. cooling issues: it is NOT uncommon; for people to rig the heck out of these Volkswagens, as people do not understand how the system works or parts of the system have fail... THUS, the fans aren't coming on. There are a number of reasons; that the fan not be coming on.
a. low coolant (air pocket; thus coolant, isn't reaching the sensor)
b. bad fans
c. bad fan control module
e. bad temp sensor(s)
f. system is rigged or disconnected, wiring damaged, wiring modified to run all the time which kills the fans, etc.
g. bad waterpump and you system is overheating, low coolant, etc.
Here is a great thread; that can help you understand how the cooling system is set up and help you start to diagnose the problems: http://newbeetle.org/forums/questio...3260-summers-coming-here-check-your-fans.html
You might want to break down your problems; show some pics of the sensor you unplugged and describe things more clearly. Organize your issues; into each sub system: cooling, brakes, etc.
If you want to confirm; the waterpump is ok, you can pull off the cooling hose and see if a stream is going back into the cooling tank. If there isn't much of a stream; you can pull the thermostat and inspect the water pump impeller. Many of the water pumps; have plastic impellers, they break, crack or spin on the shaft, which causes cooling problems.
Here are some videos; showing how to check for coolant flow:
good flow:
https://www.youtube.com/watch?v=SJN3biTfdGE
bad flow:
https://www.youtube.com/watch?v=thc...d=SJN3biTfdGE&annotation_id=annotation_233830
before and after:
https://www.youtube.com/watch?v=ZcoT1oFr74g
example of typical waterpump failure:
https://www.youtube.com/watch?v=H_7De5aU4dI
If your water pump ends up being bad; I would recommend, a timing belt and waterpump kit, these guys have great quality kits, at excellent prices.
www.blauparts.com
DON"T get discouraged; you CAN fit this thing! We are here to help!
1. brakes hissing: a common problem, is the plastic hose that connects to the brake booster will crack and cause idle issues a well. Check that and replace; if needed, that is a safety issue and could cause a accident, from poor performing brakes. Your brake booster; could also have a leak but most of the time, the hose is bad. Most likely Volkswagen part # 1J0612041AB : be sure to order with your VIN # to get the correct part.
1J0612041AB - Brake Vacuum Pipe With Check Valve - Hard vacuum pipe that goes to brake booster, comes with check valve
Hard vacuum pipe that goes to brake booster, comes with check valve
This vacuum pipe is located on the brake booster and connects to the F-hose on the left side of the intake manifold. A crack or break in this line can cause major vacuum problems and could possibly leave you stranded.
https://www.google.com/search?q=1J0...rome..69i57&sourceid=chrome&es_sm=91&ie=UTF-8
2. Check engine light; you won't know, what the reason for the light is coming on until you scan it for trouble codes. Once you get the codes; please, post them up and we will do our best to help. A generic obd II scanner; is ok but a VW specific scanner, like VCDS or a cheap volkswagen scan tool off of amazon.com is recommended (basic one like vs450 etc.).
3. cooling issues: it is NOT uncommon; for people to rig the heck out of these Volkswagens, as people do not understand how the system works or parts of the system have fail... THUS, the fans aren't coming on. There are a number of reasons; that the fan not be coming on.
a. low coolant (air pocket; thus coolant, isn't reaching the sensor)
b. bad fans
c. bad fan control module
e. bad temp sensor(s)
f. system is rigged or disconnected, wiring damaged, wiring modified to run all the time which kills the fans, etc.
g. bad waterpump and you system is overheating, low coolant, etc.
Here is a great thread; that can help you understand how the cooling system is set up and help you start to diagnose the problems: http://newbeetle.org/forums/questio...3260-summers-coming-here-check-your-fans.html
You might want to break down your problems; show some pics of the sensor you unplugged and describe things more clearly. Organize your issues; into each sub system: cooling, brakes, etc.
If you want to confirm; the waterpump is ok, you can pull off the cooling hose and see if a stream is going back into the cooling tank. If there isn't much of a stream; you can pull the thermostat and inspect the water pump impeller. Many of the water pumps; have plastic impellers, they break, crack or spin on the shaft, which causes cooling problems.
Here are some videos; showing how to check for coolant flow:
good flow:
https://www.youtube.com/watch?v=SJN3biTfdGE
bad flow:
https://www.youtube.com/watch?v=thc...d=SJN3biTfdGE&annotation_id=annotation_233830
before and after:
https://www.youtube.com/watch?v=ZcoT1oFr74g
example of typical waterpump failure:
https://www.youtube.com/watch?v=H_7De5aU4dI
If your water pump ends up being bad; I would recommend, a timing belt and waterpump kit, these guys have great quality kits, at excellent prices.
www.blauparts.com
DON"T get discouraged; you CAN fit this thing! We are here to help!
