2003 VW Jetta VR6 Coolant Pipe and thermostat replacement

In this video I will show you how to change your leaking Coolant pipe, thermostat housing, thermostat and coolant temp sensor. If you have any questions put them in comments below. If you found this video helpful please like and subscribe.
Parts list from amazon:
Coolant pipe - amzn.to/2iPIkXT
Thermostat housing- amzn.to/2iQeodY
Thermostat - amzn.to/2kkVZqa
Thermostat housing to cylinder head gasket-amzn.to/2AJzfrC
Coolant temp sensor - amzn.to/2iQLivh
Coolant plug - amzn.to/2nM0NJY

[@bpure3338]

Dang!!! Brother, you made that look way too easy!!! I'll likely be doing this job once spring gets here. I have seen several really good 'how to videos', and they were very thorough and informative, but they all seemed so much more difficult. Great video!!!

[@jrkaz6070]

you are not a natural flat rate mechanic.!.!.! you must be involved with dark magic!.!.! was that a real time shoot???RESPECT

[@ThePracticalMechanic]

Lol thanks for the comment Jr Kaz. Is there a dark flat rate spell out there? If so the caster could get rich. Some of the clips are doubled in speed and all the times I stopped to help others and time grabbing tools is cut out as well. Our shop doesn’t currently do flat rate but we may switch in the future.

[@ducman748996]

Not on mine, but my friend needs to change his. I put a billet pipe in, I think it was from ECS. This was the hardest job I ever tackled, oh and replacing the fuel injectors lol, granted I’m just a home mechanic, but we’re looking for an easier way, gonna try your method, thanks for response and vid!!

[@ThePracticalMechanic]

ducman748996 No problem. Hope this video helps make it easier. The only part I struggled with was a spring metal clip that holds a wire harness half way down the pipe. I think I used a long screw driver or pry bar to pop it loose. Good luck.

[@spectrum1com]

10,000 of us absolutely love you thank you lol

[@dunc_nasty9940]

this was so incredibly helpful coz mine is leaking coolant and it’s such a bitch to access that side of the motor so i wanted to be sure before i started a tear down. thank you so much. also is it possible to only change the gaskets and leave the existing housing? thanks man!

[@ThePracticalMechanic]

dunc_nasty typically the housing is crumbling apart so it not worth doing just the gasket. I would do it all while your in there so you don’t have to tear it down again. Good luck with the repair. 👍🏻

[@jwagner1993]

Great video! Makes me wish a Jetta V6 now!

[@nfshelper8317]

My VR6 is a bitch it's not this making it overheat tho it needed it

[@yermo130]

you are superb! thanks for this great video!

[@mot611]

What's your best guess? Pump or thermostat? My 2000 VR is overheating on the highway. It idles NP. Overheats at speed. It's winter. It makes plenty of heat. I had to top off the coolant 2x in the last 6 months. I noted a small puddle of coolant on the floor under the pump side. The oil cap is totally clean inside.

[@80KlassiK]

If its like my 2001 vr6 then good luck with that pump. mine just went out last week and was a real job replacing it. have to jack the engine up on one side to get it out. good luck

[@ducman748996]

I did this at home a couple years ago, how on earth did you remove and put back on the small hose connected to the crack pipe!! I had to take the whole damn front of the car off. Took me three days! LOL

[@ThePracticalMechanic]

ducman748996 lol just had to watch it again to find out. At 6:00 it looks like I struggle a little bit I couldn’t fit a camera and my hands in there at the same but it looks like I preload the hose clamp on my plier and then while keeping pressure on the pliers I slide the clamp onto the small hose and then wiggle the hose onto the pipe. There is a cut in the scene where I probably slipped with the pliers and had to restart. The first one I did I loosened the front clip and intake. Thanks for checking out the video. Do you have to change it out again?

[@RedondoBeach2]

@ducman748996, I was thinking the same thing. I was looking for that specific step in the video @ThePracticalMechanic, thanks for making the video. I need to do this same job on my 2004 GTI. I intend to take ducman's approach by taking off the front end.

[@bridgecard7929]

literally a perfect video

[@christophermcallaster5007]

The plug on mine (next to the coolant temp sensor) is leaking, would it be possible for me to change it without removing the whole t-stat housing from the block?? Thanks for the great video!

[@ThePracticalMechanic]

It’s kinda tight in there but I have replaced the temp sensor and plug without pulling housing several times before. I would get a new sensor, plug, 2 orings and 2 clips just so you prepared. Good luck👍🏻

[@christophermcallaster5007]

Thanks man! I had the same issue about 6 months ago and bought a whole new housing and everything only to realize when I got it apart that it was only leaking from the plug (still replaced the whole housing anyways since it was apart). I didn't anticipate this being the issue however and hadn't bought a new plug and assumed it was just the gasket. @@ThePracticalMechanic

[@christophermcallaster5007]

Will I need to drain the coolant first still? @@ThePracticalMechanic

[@ThePracticalMechanic]

I normally don’t drain it if I’m doing just the sensor and plug. Still need a drain pan underneath because some will spill but it is probably less than 0.5 gallons. I release the pressure from the cooling system and then reinstall the cap this will form a slight vacuum and slow down the coolant flow from the removed plug.

[@christophermcallaster5007]

Awesome, thanks again! Subscribed!@@ThePracticalMechanic

[@rodrigoalvarez8662]

it was real good tips to do it , thank you.

[@NelsonSeattle]

What camera are you using? I've tried a few head mounted camera and they all seem to get in my way.

[@zoejm5262]

Muy buen video me ayudo mucho gracias

[@tylerbeard4092]

Is this 12v or 24v motor? I have a 12v VR6 in my 2000 GTI, can I access the water pipe without taking down the front end?

[@ThePracticalMechanic]

tyler beard Your GTI should be very similar to this Jetta. I don’t recall if this was a 12 valve or 24 valve motor but since it’s coil on plug I’m thinking it was a 24 valve. I have pulled the front end off of these cars to replace this pipe in the past and although it’s easier to get to the pipe it does require additional labor to remove the front end off the car. I think the worst part about this is if the pipe get stuck like mine was and getting to that small hose that is just underneath the intake attached to the pipe. I would attempt it without pulling off the front end first because most of the hoses and wiring harness stuff that you have to unhook will have to be unhooked no matter what so it won’t really be a waste of time to unhook that stuff first. Also it’s very easy to change this pipe if you have the intake manifold off the vehicle but that also requires additional labor

[@tylerbeard4092]

ThePracticalMechanic thanks I’m going to the parts store now. I’ll try it without dropping the front and then if the pipe is stuck inside the block then I guess I’ll drop the carrier/bumper

[@mot611]

OK. It was the thermostat. Checked the pump and it was smooth and tight. Pulled the T and it does not operate. Bought the kit and am 1/2 way through. HOW do I know when the crack pipe is seated in the block? Does the T housing bolts hold it all together?

[@ThePracticalMechanic]

The thermostat housing as well holds the crack pipe in place. But you shouldn’t be required to use bolts to pull everything together. Everything should slide together and then you install the bolts.

[@patricklear5736]

I have question I am doing same thing to my Jetta only problem is I can't find the yellow sensor anywhere and what is it actually for I found the blue one and brown what are they actually for

[@Scouty208]

Would it be a good idea to clean the surface that the coolant pipe mounts on like you do for the thermostat housing?

[@ThePracticalMechanic]

If you can get down to it you can clean it up but it’s very hard to reach and when you pull out the old pipe a lot of the debris comes out with it. I normally just line up the oring and install the new pipe.

[@Scouty208]

@@ThePracticalMechanic Cool. Was just thinking if I'm not able to get it out this way and have to take the front of the car off I would have more room so I just wanted to see if I should do that to be thorough.

[@Scouty208]

Can I just replace the thermostat housing if that's the part that's leaking? Or is it a good idea to replace the coolant pipe at the same time while I'm there.

[@ThePracticalMechanic]

Sometimes the water pipe breaks when you disassemble it and other times the pipe is just fine. You always try changing the thermostat housing only and keep an eye on the pipe.

[@piroosehajizadeh-amini6219]

so i had my housing replaced however i think they used the same thermostat, which i believe is starting to go. Can i do this and just replace the thermostat, the housing was replaced last year?

[@ThePracticalMechanic]

As long as the housing isn’t leaking you should be able to replace just the thermostat.

[@Silas_cv1]

Im guessing this is the same as the 12v vr6 (AFP) since they both use the same 2.8L block?

[@ThePracticalMechanic]

Silas_ Mk4 it will be quite similar but there may be some slight difference and you might need to remove the ignition coil from the back of the head also.

[@sinz2010]

Are there any torque specs for the thermostat housing bolts?

[@dbjb_]

Ten nm I think

[@rapmatthew]

I’m currently doing this now. I am stuck with the coolant sensor not being able to unplug. How exactly does it come off???

[@ThePracticalMechanic]

You may have got the sensor unplugged already but if you haven’t try this. There is a little black tab on the connector as long as it isn’t broken, it works best if you push down on the connector and then pull up on the release tab, then pull up on the whole connector. If the tab is broken you can just leave the sensor attached to the connector and reuse it or use a small screw drive or pick to release the latch from the bottom of the connector.

[@coltrain7495]

When you put the new coolant pipe back into the block, did it snap into place, or does it just slide in there? I have mine put into the block, but it still comes out pretty easily

[@ThePracticalMechanic]

They just kinda slide in with a lubed up oring. They don’t have any retention except for the thermostat housing on the other end.

[@antlyons32]

Were there any wiring harnesses on the far side of the crack pipe?

[@antlyons32]

The videos I've seen before have a harness that connect to a tab on the crack pipe. I just kind of yanked mine out and I don't see any harness. I have an 01 MK4 GTI to VR6

[@coltrain7495]

@@antlyons32 I have an 01 Jetta with the 12 valve vr6, no harness here

[@spectrum1com]

PLEASE HELP!!! so I replaced the crack pipe and therm housing will all new gaskets. But now I have a slow drip leak where the pipe meets therm housing! I didnt put grease on seal but i mean would that really cause a leak this bad? Am I missing another gasket where it actually meets the plastic of therm housing. Or is the o-ring on the crack pipe enough? I did get the ALUMINUM crack pipe as well.

[@ThePracticalMechanic]

Austin Schmidt I put lubricant on the o-ring to ease installation and prevent the o-rings from getting damaged. It’s possible that the print just isn’t quite the right size or the o-ring folding over upon installation.

[@bernardaflores1720]

Is their a replacement cycle, like every 10 years or mileage for this crack pipe???

[@ThePracticalMechanic]

I don’t think there is a real interval but I see most fail between 120-150k. Different climates and coolant service intervals may change the frequency.

[@Scouty208]

You didn't have to remove the ignition coil to access the thermostat housing?

[@EXOVCDS]

This engine has 6 ignition coils, one on top of each spark plug. The ignition coil that you are wondering about is mounted / used on the earlier 12 valve vr6 engine. This one is a 24 valve.

[@ThePracticalMechanic]

Thanks Thomas for the detailed answer.

[@Scouty208]

@@ThePracticalMechanic I can see that now. Thanks for the explanation Thomas.

[@ManJunk269]

So. I'm buying a 2001 Jetta vr6. I've never worked on one. Guy told me the plastic pipe going into the radiator is cracked and needs to be replaced. Is this what I'm looking at here?

[@ThePracticalMechanic]

James Fisher III this plastic pipe goes between the water pump and the thermostat housing on the engine. There are many plastic components on this engine that can crack and fail the radiator being one of them.

[@perosity]

This is a 24v correct?

[@ThePracticalMechanic]

perosity Yes. As far as I know most of the 2002.5 and newer are 24 valve engines.

[@perosity]

ThePracticalMechanic does that have the SAI?

[@ThePracticalMechanic]

It been a while but I’m pretty sure I unhook the black corrugated SAI hose in the video.

[@stuartbachus]

You’ve probably been asked this a bunch...What camera did you use for this

[@ThePracticalMechanic]

Stuart Bachus This was done with a GoPro Hero 5 black and the GoPro head strap. I am think about replacing both of my hero 5’s with a hero 7. The 5 has reliability issues(sometimes grainy video and most of the time very poor audio). I would have upgraded them already if they weren’t so dang pricy.

[@tomthompson7400]

does this pipe give a lot of trouble , does it leak , or break

[@ThePracticalMechanic]

The orings are the most common failure but they do split sometimes. Many performance company offer an aluminum replacement to prevent splitting. The pipe and thermostat housing are probably the most common leak source on the VR6

[@tomthompson7400]

many thanks ,,, just bought a vr6 , with a low to normal to low to normal tickover ,,, hence the interest

[@jordydinong5347]

So how does the Pipe come out? You just pull it out?

[@ThePracticalMechanic]

Jordy Dinong Yes the pipe should just slide right out. There is an O-ring on both ends of the pipe the o-ring gets stuck to the metal surface of the block sometimes. In the video you can see I use a pair of pliers to grab the pipe and wiggle it until it popped out of the block. If you’ve gotten to that point and you still can’t get the pipe out on some of them there is a metal clip halfway down the pipe that gets caught on the wiring harness. So you may need to stick a long screwdriver down next to the pipe to release that clip off of the pipe. Hope that helps.

[@nivasylstrongman4352]

i have an mk4 2000 jetta 2.8L and the check engine light code come one with a error code. P1516 intake manifold changeover valve-n156 open & P0411, secondary air injection system; incorrect flow detected. please help

[@ThePracticalMechanic]

The N156 valve and the secondary air injection pump are both located under the intake manifold. Since the P1516 code is an open circuit I would check the connector first and make sure that is fully seated on the N156 valve/solenoid, if that is good then the solenoid could be bad, wiring to it could be damaged or no power from the fuse (number 34 on the side of the dash I think). The P0411 code is normally a broken vacuum line on the SIA combination valve near the rear of the engine otherwise the air pump under the intake could be bad, could be unplugged or the plastic line from the pump to the combination valve could be damaged. -TPM