Question about 1991 Toyota MR2

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91 MR2 with 107 orig. miles has no compression on

91 MR2 with 107K orig. miles has no compression on #1 cyl. I hope it's a stuck valve. Thinking of trying MMO or Seafoam gas and oil ptoducts. What do you think?

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I will do a 30W oil change and see does it free up the valve.

Crank it just enough to get a compression reading for cyc1.

I will not use MMO or Seafoam as a quick fix.


What is the compression numbers on cyc 2,3 and 4?

If they are 175 psi or above then it's worth saving.

When you drop the engine for repair,make sure to get

the water pump,
timing belt,
coolant hose and
head job done at the same time.

My friend has a valve dropped into the cyc!

It's NOT a good pretty picture.

Posted on Nov 12, 2009

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If you remove the spark plug in the effected cylinder and allpy air slowly at first to let piston move if you hear air out the exhaust it a exhaust vaulve or if out intake it a intake vaulve

Posted on Nov 12, 2009

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