How to Replace YOUR 1.8T headgasket

 Have you just found out that your head gasket is leaking/blown? Welcome to the club. One of the things I have had to do FOUR times to my 2003 a4 1.8T! The B6 A4 is riddled with coolant issues and subsequently can cause lots of head gaskets to be required. Since I’ve don’t it so many times I thought it would be helpful to have a Step-by-Step of how to do a head gasket as quick as possible.

Well, there are a few options. But first, there are some options if you really don’t want to do this job yourself

-1. Lose a few hundred on a tow truck, then take out a new mortgage for the repair to be done at a dealer.

-2. Take it to an indy shop and still pay $$$ and hope they don't mess anything up (or cut too many corners to make $$)

-3. Get some of that head gasket fixer stuff that you put in your coolant from AutoZone and see how that works out. (Please don’t do this)

-4. Do it yourself. Show all your friends and everyone at the office how amazing your wrenchin' skills are, and brag about how much you saved by doing it yourself.



First off, you're going to need all the basic tools, and some specialty tools since its an Audi.

These tools include but are not limited to the following:

Metric stuff:

8mm,10mm,13mm,15mm,16mm,17mm, and 19mm

Allen:

5mm, 6mm, 7mm, and 8mm

Torx:

T-25, T-30, T-45, T-50

Special Tools:

Factory head bolt tool (On amazon for $14)

 

Once you’ve gathered all these tools. It’s time to open the hood and tear into it.

 

The first step to doing nearly anything on an Audi is to put the vehicle in service position. I will drive my car up onto ramps before starting to get easy access to underneath, but this step is not mandatory.

The first step to service positions is to remove the headlights. The headlights are held on with 3-4 T-30 bolts. I say 3-4 because I only utilize one of the lower mounting bolts to make removal easier. Once the bolts are removed pull the headlight out and unplug and set inside the back seat. Next its time to rip the front bumper off. If this is the first time it is coming off. It won’t be pretty. There are 2 very annoying bolts facing upwards that are only accessible through the fog light grills. They are a pain to remove to say the least, once they are out through them in the trash. After these two bolts are removed there are 6 10mm nuts on the inside of the bumper located under where the headlight was. A flex head ratcheting wrench will be best but a small ratchet and a 10mm socket also work. Remove all the nuts and YANK! The front bumper will come flying off, but don’t pull too hard there are 2 electrical connectors and the headlight washer line to remove still. Have something handy to catch all your washer fluid because it will all leak out once the headlight washer line is removed. Now you are just 12 bolts away from service position yay almost to the fun part!!

 The next step is to pull the front clip forward. To do this first remove the large T-50 bolts holding the front crash struts on. After removing these bolts move to either side where the headlight mounted. With the bumper removed there are an addition 2 bolts to be removed. 1 one each side use a T-30 to take them out. Next are the last 4 bolts holding the front crash support on. They are located by the fender above where the headlight mounted. Remove them slowly. The whole core support will want to fall forward. Once they are removed and you are supporting it, pull one side at a time forward so the read bolt holds of the core support line up with the front holes of the chassis mount. Replace one bolt into this new position.

 

Congratulations your car is in service position!

 

Now the fun really begins… Before touching ANYTHING on the motor it is imperative that we set the timing. If you rip the head off and the timing somehow gets changed on either the motor or the head you are in for a world of hurt.

 

To do this take a 19mm 12-point socket and ratchet and place it on the crank pulley. Rotate the engine until the crank pulley notched and the cam shaft marks line up to their respective marks. The cam shaft has a not on the pulley and the valve cover. The crank has a not on the crank pully and the metal shield behind it.

 

Next you will begin disassembling the head/accessories. The “by-the-book” way of doing this is to remove everything off the cylinder head before removal. But that isn’t necessary. Once the Intake is off and the turbo lines are removed nothing is stopping you from pulling the cylinder head.

 

Remove the accessory drive belt. A 17mm wrench is required. Pull the tensioner back and remove the belt. There is a square notch facing upwards to pry with the 17mm wrench.

Next drain the coolant. The easiest way to do this is to find a bucket and remove the coolant temp sensor held in with a clip on the lower radiator hose located on the driver side of the vehicle.

 

After the coolant is drained start removing the coolant crossover pipe that runs on top of the intake manifold. 4 hose claps will be removed. 2 on the front, 1 in between to intake runners, and one at the rear. Once these are removed and the hoses are freed take a 5mm Allen and removed the 2 bolts holding the pipe to the intake.

 

Next disconnect the intake pipe from the throttle body. 1 hose clap and a firm pull, and it will pop off. Now disconnect the IAT sensor and the throttle body connector near the intake pipe. Next, we will remove the 10 5mm allens holding the intake onto the car. There is no need to remove the injectors will simply set the intake on the engine bay cowl. Remove the 10 5mm allens by starting at the center and working out then set the intake manifold on the cowl. This side of the engine is ready to go.

The next hardest part is the rear of the cylinder head. The easier method is to remove the entire coolant flange by removing the 2 10mm bolts holding it to the head. Once you have successfully broken your knuckles on the back be careful to not drop the O-ring that seals the flange to the head.

 

We are almost ready to pull the head just a few more things!

 

Next disconnect all the lines running to the turbo. You will need a 17mm and 19mm wrench for the coolant and oil feed lines. Simply loosen them and pull to the side. For the oil feed line, you will also have to remove the 2 7mm allens hold the hard line to the cylinder head. Simply follow the hardline from the top of the turbo back and you will find them. After these two lines have been removed remove the coolant return line from the block. This is far easier to get at than the one on the turbo. Climb under the car and reach up with an 8mm Allen and remove it. Coolant will spill out so be careful to not get it in your mouth.

While you are down there remove the 2 5mm allens holding the turbo oil drain to the turbo.

While on the turbo side remove the 3 exhaust bolts holding the downpipe to the turbo. The 3 17mm bolts can be a pain to get at, mainly the bottom one. But it is doable from the topside. Once removed pry the downpipe back and off the studs.

Now we will remove the valve cover. Simply disconnect the ignition coils. And start removing 10mm’s. There are 10 you will need to remove. 1 for a wiring harness and 9 for the valve cover. Start yanking them out as you see fit. Pull the valve cover off and you are greeted with the inside of your engine. Only a few more things and it will be time to show your strength!

With the valve cover off you can remove the timing belt. Take your 7mm allen and stick it in the tensioner and give it a good snug down to hold it in place. Then remove the timing belt.

Now its time to remove the head bolts and rip the head off. Take your special head bolt tool and start at the middle on the intake side. Then the same middle on the exhaust. Then move towards you one row on the intake side. Then move to the back side on the next from on the exhaust side. Then the one next to it and back to the front side. Follow this pattern for all 10 head bolts.

 

Now LIFT! And the head will come off. Although its made of aluminum it is HEAVY so a team lift is recommended. Be careful to make sure you didn’t snag anything on the way out and be gentle setting it down.

 

For the last step, simply remove the head gasket, inspect for damage, and put the new one on. Then reinstall as you took everything off. It’s just that simple!