well the flange gasket on my drivers side has been leaking for a while, had a couple holes that blew out that were about 1/8th inch wide each. Been too lazy to fix it, but I noticed that my mileage has gone down about 5 mpg or so from when I got the car. I am trying to remember, but I think it dropped about the same time the exhaust started leaking.

Fast forward to three days ago.... driviing to work and POP! rattle rattle rattle. Car now sounds like a sick haarley... turns out I blew about a 2 inch chunk of the flange gasket out, now i have a MAJOR leak.

I bought the gasket and got set to put it in... Hmm, car is an 89, and the bolts are rusty as all get out. How to take them off... soaked them in PB Blaster over night. next morning I tried to unbolt them.... Hmm... I had more leaks than I knew... Turns out the header bolts were coming loose from the block. 3 of the six were finger tight! on the rear exhaust port half the gasket was missing, and on the other two ports there was marks from lots of blowby due to the loose bolts. so I ran back to the parts store and got the header gaskets. now that it is all buttoned up it runs like a champ.

Good things:

fixxed MANY leaks.
Tightned bolts that were WAY to loose.
discovered that the coolant hose running to the throttle body is starting to swell like it wants to pop. gotta fix that now, but Im glad I noticed it now, rather than when I am running down the road to work and it blows!

 

Just for your knowledge, originally the manifolds did not have gaskets. Or did you or someone else in the past put headers on this car?

 

factory cast iron manifolds to the 'Y' pipe. No gasket? the manifold was tapered in, and so is the 'Y' pipe. I needed a gasket that was roughly shaped like \_/ to fit. as far as I know this is all factory... Hmmm. I love buying used cars. fixing things when you dont know they are NOT origional is SO much friggin fun....

On a side note, just took it for a nice long drive... My power is back and then some, and the hesitation that I had off Idle is now gone. Just waiting for it to cool off so I can pull the TB cooolant hose and replace that. Might bypass the TB while Im at it, but thats or a different section.

 

Exhaust leaks suck outside air in, which causes the 02's to think you're running lean. Hence it dumps more fuel in to richen it up.

 

well just got home from work, and after 187 miles the gasket I just put in is blown out. Im gonna just try taking it out and seeing if that will seal. Im really getting to hate this stupid issue. we got about 7 inches of snow two days ago, and now I get to lift my car a but and lay in it to get under the car! ARGH!!!

 

Get some red sealant and put a light coating on both sides of the gaskets when you install them

Most people swear its for headers only but Ive found regular manifolds need heat cycling of the bolts as well. Yes they will blow out after even 187 miles if you never retighten the exhaust bolts

 

well I found a different gasket that is a bit thicker so Ill try that. it is already back together right now so I cant really put the sealant on it... if it blows agaiin Ill try that. yea, the bolts did loosen up a bit on me after running it. diddnt think about that untill I started tearing it apart. Oh well live and learn. only problem with re-tightening it is that the power steering pump has a bracket that covers the bottom bolt on the front of the manifold so in order to tighten it I have to pull the AC compressor and the power steering pumps off. Not difficult, but a definate pain.

 

well I have run the car to heat the engine and exhaust a few times and tightened the bolts again when Its cooled off, now they no longer are loose when I go to re-tighten them. so I guess thats good.

Now for the bad...

heard an exhaust leak on the passengers side... and tried to tightn some of the bolts there to maybe seal it up... yep, I stripped the threads for the top bolt in the front cylinder.... I tested with a wire to see how deep the bolt hole is and it seems to be about 1/2 inch longer than the actual bolt is, so I m going to try to get a longer bolt and see if I can salvage this. Hopefully there will be enough threads behind the stripped part to tighten it, as I am NOT pulling my head off for this.

 

well I seem to have gotten all the leaks taken care of now, and My mileage has come back up to 21MPG! WOO HOO!

 

I run dead soft aluminum gaskets on my headers, no blowouts. I used to replace gaskets about every time I changed the oil. Those dead soft aluminum header gaskets are worth every penny!!!!!