2 Blown headgasksets in 1 year, STOCK DSM

[Arrow_Runner]

Wife was driving the TSi home from work yesterday and smoke started pouring from the car. She pulled over and when I got there there was a huge puddle of oil under the car. (Blown head gasket)

This is the second hg to blown within a year on the car and it is STOCK, the only thing done to it was a PnP to the head by a local guy last year after the first HG went (warranty then).

1. I didn't think stock dsms were prone to blowing headgaskets like this, any thoughts? The shop that replaced the first one said that the head bolts were loose on the side leaking oil. WTF causes that? Thermal expansion, sonic vibration and an alignment of the planets?

2. I found oil in the intake pipe, I suppose the blown hg could have let oil go into the combustion chamber/exhaust and the turbo pushed it back into the intake. Anyone agree w/ my theory?

BTW, I'm going to try to do the HG replacement this time around since the warranty ran out 3 weeks ago...

Also, would it be wise to have the head milled again for flatness?

I believe they milled it .005" last time. Would requesting more for higher compression be a bad idea on stock everything?

 

[Arrow_Runner]

I put a Mitsu HG and Arp studs on. I torqued them to 65lbs. Does anyone question that?

 

[dsm-onster]

I've been out of town...

is this 65 ft-lbs using the moly lube provided in the ehad stud kit? or using motor oil. I torque mine about 10 lbs over recommended using 10-30w motor oil. 110 ft-lbs is recommended for motor oil. 85 ft-lbs is recommended w/ the moly lube. Either lube, you need to torque it in "stages".

 

[Arrow_Runner]

Thanks for the reply. I should have searched before posting the question though, but this is where I'm at.

Torque at 80 ft/lbs.
HORRIBLE idle. Sounds much better at 1.5k+ RPMs
Coolant leak, probably from thermostat housing.
Feels like the power brakes aren't working. I have to push very hard and the car slowly slows and stops.
The timing belt is actually getting a little worn on the non-teeth side closest to the engine.

I think I may have the timing off and it's causing most of these problems. Hopefully the coolant doesn't mean the hg didn't seal, but the brakes thing has me baffled, but I haven't got to take a good look at it for a few days. Do they run off of a pump or vacuum line?

 

[zimfro]

The brake Booster runs off of vacuum. If you have the timing off, your engine may not have as much negative pressure (vacum) in the intake manifold, hence the crappy brake feeling.

 

[dsm-onster]

Thanks for the reply. I should have searched before posting the question though, but this is where I'm at.

Torque at 80 ft/lbs.
HORRIBLE idle. Sounds much better at 1.5k+ RPMs
Coolant leak, probably from thermostat housing.
Feels like the power brakes aren't working. I have to push very hard and the car slowly slows and stops.
The timing belt is actually getting a little worn on the non-teeth side closest to the engine.

I think I may have the timing off and it's causing most of these problems. Hopefully the coolant doesn't mean the hg didn't seal, but the brakes thing has me baffled, but I haven't got to take a good look at it for a few days. Do they run off of a pump or vacuum line?

The brakes are vacuum assist. There is a large vacuum hose going from the intake manifold plenum to the brake booster. If this is disconnected you have a HUGE boost leak that will kill idle and will screw with your brakes. It needs to be removed when the intake manifold/head assembly is removed from the bay. So if you've done a head gasket, then it's possible that hasn't been reinstalled.

Trace the coolant leak. Did you start the car w/ the studs torqued to 65 ft-lbs?

Double check timing. We can't say how worn your timing belt is because we don't have a pic. To err on the side of caution: if you feel it is worn, replace it.

 

[Arrow_Runner]

The brakes are vacuum assist. There is a large vacuum hose going from the intake manifold plenum to the brake booster. If this is disconnected you have a HUGE boost leak that will kill idle and will screw with your brakes. It needs to be removed when the intake manifold/head assembly is removed from the bay. So if you've done a head gasket, then it's possible that hasn't been reinstalled.

Got a pic of the line?

Trace the coolant leak. Did you start the car w/ the studs torqued to 65 ft-lbs?

Car was only started at 80, does this mean anything? I did use the moly-lube.

Double check timing. We can't say how worn your timing belt is because we don't have a pic. To err on the side of caution: if you feel it is worn, replace it.

Will do!

I forgot to mention, I did a compression test just to see if things were really bad or close to good, and this is pretty much what I got, I don't have the paper in front of me so I don't remember which number correlates to which cylinder.

187-187-183-183 - Not necessarily in that order.

Or something like that. I'm pretty sure that is actually a little too high. I know carbon build up causes this, but would the timing being off cause this as well? Just curious. It would seem to make sense that if the valves were closed completely with the piston up just a tad higher I would get higher compression.

 

[dsm-onster]

Got a pic of the line?



Car was only started at 80, does this mean anything? I did use the moly-lube.



Will do!

I forgot to mention, I did a compression test just to see if things were really bad or close to good, and this is pretty much what I got, I don't have the paper in front of me so I don't remember which number correlates to which cylinder.

187-187-183-183 - Not necessarily in that order.

Or something like that. I'm pretty sure that is actually a little too high. I know carbon build up causes this, but would the timing being off cause this as well? Just curious. It would seem to make sense that if the valves were closed completely with the piston up just a tad higher I would get higher compression.

Yea compression numbers can actually go UP if your cams are advanced a bit.

Good that you didn't start the car until you verified the torque. If there wasn't enough torque on the head studs and you started it up, clearly a new head gasket is in order. But, for now just double check your timing and find the source of that coolant leak.

You have a 1995. But I THINK both intake manifolds have this port in around the same spot. It's been a while since I've been uner the hood of a 2g. . .

Here are some pics of my 1G brake booster line:

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View from passenger side engine bay.

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View from driver side

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Where line feeds to brake booster (driverside view).

Hope this helps.

 

[Nors]

Did you make sure you blew all the material that could have gotten into the headstud bolts out?? If there is anything in those holes like oil, or water it will give you wrong readings on your torque wrench.

Also like they mentioned could be stretched studs, or warped block/head. If you didnt clean the head stud bolt holes out then I bet thats your problem.

Oil would not affect torque negatively, in fact they recommend using oil to lube the bolts.

 

[Arrow_Runner]

Update:

Found what was wearing on the t-belt. It was some metal shielded wiring. I bent it back, no more wearing now I'm sure.

Timing marks were all lined up. I redid it anyhow thinking that the tension was too low. That didn't help.

I believe that the brake booster is hooked up. On my 2G, it looks like it's located close to the throttle body.

There is a slight hissing noise while the car is running. Is that normal? What's the best way to trace it? Soapy water or a stethoscope?

I ran some Seafoam through the intake, didn't seem to help any.

It still idles like crap, but once it gets above 1300 rpms it sounds like it should. Haven't looked for the coolant leak yet.

 

[motomattxxx]

The hisssing in a 2g is normal.

 

[dsm-onster]

Oil would not affect torque negatively, in fact they recommend using oil to lube the bolts.

ARP head stud kit states that torquing 12 mm studs to the proper max torque w/ moly lube is 86 ft-lbs. When using 10 wt. oil a torque of 109 ft-lbs is needed to achieve the same fastener pounds preload.

There is a slight hissing noise while the car is running. Is that normal? What's the best way to trace it? Soapy water or a stethoscope

Really, I think the best way to trace it is w/ a boost leak test using soapy water. Have you done a boost leak test yet?

 

[Arrow_Runner]

I have never in my life done a boost leak test. I'll get on it tomorrow. I'm sure I can find a how-to fairly easily.

 

[dsm-onster]

How to build an Intercooler Pipe Pressure Leak Tester

5HP and 8FT-LBS for FREE(well almost)!!!! (newbies read this!)

Boost leak test how to with boostpro.net tester

Build a boost leak tester for your to4e

 

[Arrow_Runner]

I pretty much made this boost leak tester : http://www.dsmtuners.com/forums/showthread.php?t=209898&highlight=boost+leak+tester

It won't hold any pressure at all. I don't think there's a leak at the tester, and I know it's pushing air up through the intake pipe. I took it off and tried to seal it with my hand.

The people that first had my head tested it and said the valve seals were "marginal" I'm guessing that would affect this?

Also, do I need to be at TDC or something for this to work better?

The only possible leak I have found so far is a small one at my BISS.

Edit: Nevermind, Huge leak at the intake/head gasket.

 

[dsm-onster]

Edit: Nevermind, Huge leak at the intake/head gasket.

At least you tracked your problem yourself. Do some searches on pulling the intake manifold. It can be a PITA. But, I wouldn't pull the head just to get the intake manifold off like some have the custom to do. No sense in flushing $40+ for a head gasket down the drain. There is a support bracket, so don't forget that. There are two bolts on the intake manifold and one on the block for that bracket.

 

[Arrow_Runner]

So it turns out the wrong intake manifold gasket was in the head gasket set I got from autoboys. The holes in it were so big that they left the bottom 2 corners of each port wide open.

Let this be a lesson to me and others: Compare your old gaskets to your new ones!

Matt and everyone else, thanks for your help all the way. The car is running at about 87% right now. It holds pressure good now. I have to fix the coolant leak once the engine cools down and get the base idle speed back under control.

 

[dsm-onster]

So it turns out the wrong intake manifold gasket was in the head gasket set I got from autoboys. The holes in it were so big that they left the bottom 2 corners of each port wide open.

Let this be a lesson to me and others: Compare your old gaskets to your new ones!

Matt and everyone else, thanks for your help all the way. The car is running at about 87% right now. It holds pressure good now. I have to fix the coolant leak once the engine cools down and get the base idle speed back under control.

Na! you're running about 92.8% . Bloody 95% of the dsms out there have some sort of an idle issue.

Thanx for following throught w/ the solution to your problem. This thread is now a great reference.

 

[Arrow_Runner]

Update to the idle problem:

Found a leak at the BISS screw, fixed that. Found a ripped vac line, fixed that. Still had a bad idle.

When I started the car up, I swore I could hear a "zapping" sound coming from the intake manifold...

Turns out the Bosch wires I just got after literally ripping the old ones out were bad! I can see sparks all over the place! I'll be replacing them tomorrow and everything should be back to normal!

 

[jawar666]

Well I think this thread has been a very good example of why a boost leak test should be done to the car from time to time...

Thanks Arrow_Runner for keeping the thread updated about the issues and fixes you have gone through so far...