New head gasket?
Thread Starter
Instructor
Joined: Mar 2004
Posts: 141
Likes: 0
From: Burbank IL
New head gasket?
I think I need a new head gasket but before I go ahead and do it I wanted to see what you guy think. The car runs fine no white smoke but after it heats up and the thermostat opens the idle starts to get erratic between 500 - 1000 rpm and it starts to smoke a lot out of the exhaust. Could it be anything else?
Drifting
Joined: May 2007
Posts: 1,440
Likes: 19
From: SW Chicago Burbs IL
You need a leak down tester and an air compressor:
http://www.harborfreight.com/cpi/cta...emnumber=94190
These are basic instructions I found on a random page online:
http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm
Good luck,
Matthew
http://www.harborfreight.com/cpi/cta...emnumber=94190
These are basic instructions I found on a random page online:
http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm
Good luck,
Matthew
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Have you noticed any loss of coolant? Oil?
If not, you may be having a similar problem to what I was experiencing. I thought my head gaskets were bad, the smoke looked white to me.
I followed some of the advice of the forum members and checked my fuel pressure, bingo! My injectors had failed, and since you have a 90, you have multecs. I'm not saying thats your problem, but its definitely a good possibility.
If not, you may be having a similar problem to what I was experiencing. I thought my head gaskets were bad, the smoke looked white to me.
I followed some of the advice of the forum members and checked my fuel pressure, bingo! My injectors had failed, and since you have a 90, you have multecs. I'm not saying thats your problem, but its definitely a good possibility.
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Melting Slicks
Joined: Jul 2004
Posts: 2,018
Likes: 1
From: OR
Does it go through a lot of coolant?
Remove the radiator cap and start it. If there's a head gasket leak from a cylinder to the water jacket there'll be a steady stream of bubbles. That's the poor mans method to do a leak down test. Warm or cold should make no difference.
Whatever you do get a good diagnosis. A head gasket is a big repair to do yourself, expensive to pay someone else to. It'd be the ****z to go to all that trouble and have the same problem, or even create some additional ones while not solving the original one.
Remove the radiator cap and start it. If there's a head gasket leak from a cylinder to the water jacket there'll be a steady stream of bubbles. That's the poor mans method to do a leak down test. Warm or cold should make no difference.
Whatever you do get a good diagnosis. A head gasket is a big repair to do yourself, expensive to pay someone else to. It'd be the ****z to go to all that trouble and have the same problem, or even create some additional ones while not solving the original one.
Thread Starter
Instructor
Joined: Mar 2004
Posts: 141
Likes: 0
From: Burbank IL
I finally got a chance to do the leak down test and after doing 2 cylinders I stopped neither one ever lost less than 20%. it sounded like the air was coming out of the valve covers so does that mean the piston rings have gone bad? I haven't started the car for at least a week could that cause the piston rings not to seal well enough?
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
I finally got a chance to do the leak down test and after doing 2 cylinders I stopped neither one ever lost less than 20%. it sounded like the air was coming out of the valve covers so does that mean the piston rings have gone bad? I haven't started the car for at least a week could that cause the piston rings not to seal well enough?
Have you checked your PCV valve is OK?
White smoke would indicate water and an erratic idle could be another indication of a bad head gasket.
Any signs of water in the oil,or conversely,any signs of oil in the water?
I don't understand the bit about-"once the t-stat opens".
Bad rings will give you blue smoke,not white.
And no,not starting it wouldn't cause that problem.Mine sat for six months out of the year for twelve years and no problems.
Check out ALL the cylinders and re-post.