86 cutlass supreme I was told the transmission was not bad but cannot go over 40 on the freeway what can it be

Brian Day

Asked by Dec 15, 2014 at 08:08 AM about the 1986 Oldsmobile Cutlass Supreme

Question type: Maintenance & Repair

5 Answers

Mark Grignon

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.

1 out of 1 people think this is helpful.
Best Answer
Brian Day

It switches gears but when on highway is like I have no power at all but thanks for the advice

Mark Grignon

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.

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.

Claude Masson

My daughter had the same problem of speed not exceding 49 mph. The problem was a clogged catylist convertor.

Your Answer

Add photo

Related Questions

Cutlass Supreme

Looking for a Used Cutlass Supreme in your area?

CarGurus has 141 nationwide Cutlass Supreme listings and the tools to find you a great deal.


Search Oldsmobile Cutlass Supreme Questions

Oldsmobile Cutlass Supreme Experts

#1 munron
Reputation 540
#2 tennisshoes
Reputation 350
#3 Tom Demyan
Tom Demyan
Reputation 310
View All

Related Models For Sale

Used Chevrolet Monte Carlo"
16 Great Deals out of 2,070 listings starting at $2,000
Used Buick Regal"
189 Great Deals out of 10,600 listings starting at $1,995
Used Chevrolet Impala"
946 Great Deals out of 35,750 listings starting at $700
Used Chevrolet Caprice"
201 listings starting at $10,900
Used Ford Mustang"
715 Great Deals out of 41,252 listings starting at $900
Used Pontiac Grand Prix"
28 Great Deals out of 4,397 listings starting at $1,972
Used Chevrolet Camaro"
811 Great Deals out of 38,791 listings starting at $2,650
Used Pontiac Firebird"
11 Great Deals out of 895 listings starting at $2,900