91 Thunderbird SC dogs out at about 3000 RPM going down the road, idles fine

LAWMANFIVE

MEMBER
1991 FORD THUNDERBIRD
130,000 MILES

91 T-Bird SC 3.8 liter
idles fine, loses power and starts hesitating at about 3000 rpm going down the road. "Dogs out."
Exhaust not complete. From manifold, has the 2 catalytic converters then join into what I believe is the muffler(or another catalytic converter?Please answer that 2 please) and thats it for exhaust system at the moment. Everything else ok as far as I know.

also been told it has had the "computer chip" installed for extra horsepower, that may be of importance. Also, entire engine has been replaced. Bought the car from others who replaced it and am trying to get it back on the road. Hasn't been on road since engine replacement.

I will donate based on results. I will book mark your website and donate regularly if you are an excellent source for such car repair questions. I have more questions about other vehicles and probably more questions on my sons T-Bird SC.

1 Reply

HMAC300

MECHANIC
48,601 POSTS

You probably have three converters, two pups an done regularone. Check the fuel pressure first and scan for codes before anything as there may be a problem with one of those. Also check your vacuum at idle if it's 15" or below suspect a clogged converter. If there are any sensors that aren't plugged inor any vacuum lines disconnected check that. Also no holes in the air ducts leading to the throttle body. Lastly if you have a K&N or similar air filter clean the maf as they tend ot get overoiled and cause problems.