73 Cadillac deville, runs good at low rpm but when you step on it, it runs rough and has no power. I have done a tune up with plugs, points and replaced fuel pump. What next?

15

Asked by May 20, 2012 at 09:49 AM about the 1973 Cadillac DeVille

Question type: Maintenance & Repair

9 Answers

12,285

Check the catalytic converter. If it's plugged you will have similar symptoms.

1 out of 1 people think this is helpful.
1,865

Your fuel line from the tank to the fuel pump may have a small hole in it. Then your fuel pump would be pulling some air into the fuel line, giving poor performance under load.

1 out of 1 people think this is helpful.
15

I checked fuel line for small holes, it is OK. How do you check to see if catalytic convertor is plugged? Do you have to take it off to check it?

1 out of 1 people think this is helpful.
12,285

Usually when cat is plugged the exhaust has a hissing noise instead of a rumble.

1,865

I would try to run a temporary rubber fuel line to the fuel pump, and see how it runs. I suppose you have a new fuel filter. If it is carburetor-ed, the carburetors' jets could be plugged. If the cat is possibly plugged you would have to remove it, to see.

15

There is no cat on this car. Thanks for the ideas tonythe woodsman and aztec626bf. What next? I'm guessing it must be in the carb, which is a quadrejet. I am reluctant to tear into it as they are a complicated carb.

12,285

If you go to the Carburetor Exchange you can get a kit and they supply a very helpful schematic with the kits.

15

i have the carb kit ordered, will try that next.

15

i finally found the problem! It had a double walled exhaust pipe from the y-pipe to the muffler, the interior wall had collapsed. Installing a new exhaust pipe did the trick. It now runs great.

Your Answer

Add photo

Related Questions

DeVille

Looking for a Used DeVille in your area?

CarGurus has 1,991 nationwide DeVille listings starting at $1,600.

ZIP:

Search Cadillac DeVille Questions

UK Questions

Are you a UK consumer? CarGurus now has a discussion forum in the UK.

Cadillac DeVille Experts

#1 kikero
kikero
Reputation 1,970
#2 Js08016
Js08016
Reputation 1,490
#3 Cynthiasmith
Cynthiasmith
Reputation 1,430
View All

Related Models For Sale

Used Cadillac Eldorado
397 listings starting at $2,600
Used Chevrolet Impala
937 Great Deals out of 35,462 listings starting at $1,995
Used Dodge Charger
469 Great Deals out of 29,730 listings starting at $2,275
Used Ford Mustang
582 Great Deals out of 41,215 listings starting at $1,699

Used Cars For Sale

2005 Cadillac DeVille For Sale
287 listings starting at $2,950
2004 Cadillac DeVille For Sale
265 listings starting at $1,777
2003 Cadillac DeVille For Sale
247 listings starting at $1,600