[Caseymacan]

View attachment 230246

1 - Remove Bolts from Engine Wiring Harness, 2X, (Note. there is one on the Passenger side and one behind the Harness, towards the firewall). this will allow to lift the plastic wiring harness piece.
2 - Proceed to remove the Coolant Line from the Engine Cylinder Head and from the hose locate behind the wiring Harness.

Questions: 1.) How long did this coolant hose take to remove?
2.) Can I use all the existing bolts that are removed and don’t bother w new bolts correct?
3.) When you disconnect the rail fuel line is there any gas leakage?
Excellent detail write up and changing mine this weekend. Thanks

 

[SilverFlash]

Started this today. Any advice on getting the back end of the pipe off? I've reached the end of the steps, but the harness box dosent lift up very far and I can't really get to the spring clamp holding the end.

 

[Caseymacan]

Started this today. Any advice on getting the back end of the pipe off? I've reached the end of the steps, but the harness box dosent lift up very far and I can't really get to the spring clamp holding the end.

Did you get the back end of pipe off and if so how?
How long should I expect to replace?
Thanks, doing it this weekend.

 

[SilverFlash]

Did you get the back end of pipe off and if so how?
How long should I expect to replace?
Thanks, doing it this weekend.

After the harness is loose, grab both ends of the hose and pull up hard to get it out of the clamp, then push the hose further back to get better access behind the harness box. You can also disconnect the other end of the rubber hose it connects to since it has better access and squeeze the rubber hose under the harness box as you pull forward, but it's tight.

I am no mechanic, and it took about 3 hours to disassemble. I am still waiting on my dealer to get the new hose in, hopefully today so I still need to reassemble. Some steps in part 2 could be expanded as well since the goal of PT 2 is to remove the black box the air pump is sitting in.

 

[Caseymacan]

After the harness is loose, grab both ends of the hose and pull up hard to get it out of the clamp, then push the hose further back to get better access behind the harness box. You can also disconnect the other end of the rubber hose it connects to since it has better access and squeeze the rubber hose under the harness box as you pull forward, but it's tight.

I am no mechanic, and it took about 3 hours to disassemble. I am still waiting on my dealer to get the new hose in, hopefully today so I still need to reassemble. Some steps in part 2 could be expanded as well since the goal of PT 2 is to remove the black box the air pump is sitting in.

Thanks and good luck 🍀.

 

[SilverFlash]

Done, this was the hardest DIY car project I've done. Probably 6 hours to just replace the tube. But I had to pick at my valves and loosen up some Carbon, which involved pulling the plugs and scoping the engine so i put probably 10 hours into it, 150 for the part and coolant, and a week of stress. If you paid less than 1k for this, you won.
Don't forget to pop your coolant bleeder valve open when you fill it up at the end and leave it open for your first runs. The metal clip/switch falls down when pressure equalizes.
Also if you try to carbon clean, roll the car out of the garage before restart like my wife recommended. Ive spent my morning mopping the garage from the soot.

 

[RADHAUS]

Done, this was the hardest DIY car project I've done. Probably 6 hours to just replace the tube. But I had to pick at my valves and loosen up some Carbon, which involved pulling the plugs and scoping the engine so i put probably 10 hours into it, 150 for the part and coolant, and a week of stress. If you paid less than 1k for this, you won.
Don't forget to pop your coolant bleeder valve open when you fill it up at the end and leave it open for your first runs. The metal clip/switch falls down when pressure equalizes.
Also if you try to carbon clean, roll the car out of the garage before restart like my wife recommended. Ive spent my morning mopping the garage from the soot.

So, over the past two weeks, coolant has been mysteriously disappearing from my coolant tank until the point the other day where it became more than just adding a splash of coolant every couple days.

I took it into my Indy, and mentioned this specific issue. Sure enough, that’s my problem.

I just got the call from my Indy - they want $1023 (tax included) to replace the hose, a cracked “cross pipe”, and new gaskets. I debated sound this repair myself. Reading this exact post is what made me commit to having the Indy do the job.

I’m definitely a DIYer and always happy to save a couple bucks when available, but after reading this, I think this one is best left to the pros. Especially considering I need it done for a 600mi road trip in the next 48 hours.

 

[Gatorman]

The fuel rails are a one time use, did you replace those as well?

 

[SilverFlash]

The fuel rails are a one time use, did you replace those as well?

I did not, and I am not worried about them, all solid metal and its pretty easy to tell if they fit back together well. Not even sure about the one time use claim since Porsche recommends replacing the low pressure line from the tank, not the high pressure rail lines when they replace the high pressure pumps.

 

[Gatorman]

I did not, and I am not worried about them, all solid metal and its pretty easy to tell if they fit back together well. Not even sure about the one time use claim since Porsche recommends replacing the low pressure line from the tank, not the high pressure rail lines when they replace the high pressure pumps.

I apologize I meant the fuel supply lines are a one time use.

 

[120mph]

View attachment 230246

1 - Remove Bolts from Engine Wiring Harness, 2X, (Note. there is one on the Passenger side and one behind the Harness, towards the firewall). this will allow to lift the plastic wiring harness piece.
2 - Proceed to remove the Coolant Line from the Engine Cylinder Head and from the hose locate behind the wiring Harness.

quick question tho! what are the torque specs for bolts/screws needed to assemble everything back?? thanks a bunch

 

[ELerner61]

Reading these posts it sounds like the failure of this hose is not an IF...it's a WHEN, and it will eventually happen to everyone anywhere beyond 40K miles/4 years. Do folks think I'm right?

 

[Santirx]

Reading these posts it sounds like the failure of this hose is not an IF...it's a WHEN, and it will eventually happen to everyone anywhere beyond 40K miles/4 years. Do folks think I'm right?

I tend to agree with your thoughts.

But there are conditions that will accelerate / decelerate this failure mode. I don’t know what these conditions are, but we could speculate.

Failure mode is normally that tubing becomes brittle and fractures… what can cause that? Is it the water/antifreeze? Or is it exposure to a non-compatible substance, that combined with high temperature cause this condition? Is Porsche (or the supplier) using different sources of material build this tubing?

The variability in failure timing is just too high, and is not a one off (a few folks experiencing this at a very broad mileage range), which tells me that there may be something related to the material of construction itself, but maybe related to specific production batches. This is all speculation, lacking scientific / engineering data on this.

In my case, my Macan has 115K miles and north of 7 years with no failure on this specific component (although I already had a failure on thermostat)…

 

[ELerner61]

I tend to agree with your thoughts.

But there are conditions that will accelerate / decelerate this failure mode. I don’t know what these conditions are, but we could speculate.

Failure mode is normally that tubing becomes brittle and fractures… what can cause that? Is it the water/antifreeze? Or is it exposure to a non-compatible substance, that combined with high temperature cause this condition? Is Porsche (or the supplier) using different sources of material build this tubing?

The variability in failure timing is just too high, and is not a one off (a few folks experiencing this at a very broad mileage range), which tells me that there may be something related to the material of construction itself, but maybe related to specific production batches. This is all speculation, lacking scientific / engineering data on this.

In my case, my Macan has 115K miles and north of 7 years with no failure on this specific component (although I already had a failure on thermostat)…

Good mail. Looking at that hose in pieces kind of makes me cringe. For something so critical to get that brittle makes me think I'd love to take that potential failure off the table. The replacement hose is so cheap, I might just put it on the "preventative maintenance diy project" list.

 

[torresfe]

Does anyone happened to have Porsche instruction for this hose replacement. I'm interested on the torque specs for the intake manifold bolts and any others that may be needed.

 

[Caseymacan]

View attachment 230244

2nd Picture

1 - With the intake plenum removed, proceed to remove the Secondary Air Pump. 3X Torx Screws must be removed and Disconnect the plug.
2 - Disconnect Solenoid Valve #1
3 - Disconnect Solenoid Valve #2
4 - Remove Fuel line (bridge between both fuel rails)
5 - Remove Connector (Fuel Rail Sensor)
NOTE: Red arrow is the Coolant Line that is broken

How long will this take to perform?
Any helpful hints?
Excellent post to give the confidence I can do it.

 

[AnotherMacanOwner]

Add me to the list, I'm just so glad it's not a head gasket. So a few questions to those that have done it. Is there anything else I should do while I'm in there? 2015 Macan Turbo, about 75,000 miles. Plugs were changed according to carfax (Previous owner) at the 60k mile service in 2019 by a Porsche dealer. Apparently the 70k mile service was also performed by a Porsche dealer in October of 2020. I'm guessing the intake valves should be cleaned, are y'all just spraying them with berrymans or equivalent and then allowing it to evaporate? Or walnut blast, or something else?

I don't see any record of the trans fluid change. Should it be changed? I'm changing the oil and sending it to blackstone for analysis. I don't drive a lot (Obviously) so I know she doesn't get to burn off residual fuel all that much, so I want to see what kind of fuel dilution I'm getting at 6 months of use.

Lastly, this might sound a bit improper on a Porsche forum, but I'll throw it out there anyway. Has anyone considered replacing the plastic tube with a regular old rubber hose and brass tee fitting? I had another non Porsche where the plastic wye cracked, so I replaced with regular rubber hoses and a brass tee fitting, and I'm sure it will outlast the rest of the plastic lines.

Thanks everyone!

 

[pangosaurus]

Looks like this just hit me yesterday. 2015 Macan S, 40k miles. I'm not exactly sure it's the same issue but I did find a crack on the passenger side so highly suspect it is.



I am no mechanic and sit in front of a computer all day. Considering if I should DIY this or ask a mechanic for help. Any suggestions for other brittle parts to replace while it's apart?

 

[ELerner61]

Looks like this just hit me yesterday. 2015 Macan S, 40k miles. I'm not exactly sure it's the same issue but I did find a crack on the passenger side so highly suspect it is.



I am no mechanic and sit in front of a computer all day. Considering if I should DIY this or ask a mechanic for help. Any suggestions for other brittle parts to replace while it's apart?

For those that have had this problem, is that where it usually initially cracks (at the front connection)?

 

[pangosaurus]

Started this on the weekend. Got the manifold removed in an hour going slowly. Part 2 seems tricky.

One thing I noticed is that fuel squirts out when you open any doors. Wrap those lines with some rags.

Is it recommended to get new gaskets for the intake? How about o-rings on the crankcase vent valves?