86 cutlass supreme I was told the transmission was not bad but cannot go over 40 on the freeway what can it be
5 Answers
Is the transmission shifting out of low (1st) gear? I believe the 86 cutlass still had vacuum assist and electronic overdrive on the transmission. Make sure the vacuum line is intact going to the transmission. There may be a valve body issue not allowing it to shift out of 1st.
It switches gears but when on highway is like I have no power at all but thanks for the advice
Another issue you may be having is a blockage in the catalytic converter. If you have access to a vacuum gauge, check the vacuum on the manifold. Normal vacuum should be around 12-15. If you have a steady drop in vacuum when at idle, that would indicate a blockage in the exhaust system.
migration_ftac answered 9 years ago
That vehicle may have a vacuum advance on the distributor that may be faulty.Check all your vacuum lines on the engine.Starting with the distributor.There should be a vacuum line and emission diagram under the hood or on the cross member above the radiator(rad) . If you don't find the diagram there check online for it.If you have any cracked vacuum lines, replace them.Even the slightest leak can be a headache.
My daughter had the same problem of speed not exceding 49 mph. The problem was a clogged catylist convertor.
