1990 Park Avenue backfire when downshifting

1990 BUICK PARK AVENUE
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DAWGME85
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1990 Park Avenue, 109000 miles, 3.8l (non-Ultra). I have been experiencing a mis-fire (backfire) when downshifting under light load, usually when going up a slight incline. I have replaced plugs and wires, and, after noticing a more pronounced miss at idle (when the engine is warm), checked compression, which turned out to be ok (115-125 psi).
The check engine light has not come on, yet, but I was wondering if there is a way to interrogate the OBD1 diagnostic codes through the Climate Control Console? The code scanners that I've seen for sale all seem to indicate that they do not work with Climate Control systems, which this car has.
If it is possible to access the DTC's through the CCC, what are the "keystrokes" I need to use to do so?
Thanks in advance...

LeRoy
Aug 14, 2007 at 2:17 PM
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2CARPRO JACK
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Doesnt look like your car is capable of on-board diagnostic. If it runs rough, then the reason must be found before trying to eliminate any kind of other issues.Check spark at every plug to be sure it is strong (blue). If all is ok, I would lean toward an injector, the 3.8's had a little bit of an issue with them.
Aug 15, 2007 at 4:08 PM
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DAWGME85
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Thanks for the info, 2CarProJack. It seems to be missing worse, and the SES light finally came on last night while I was driving it around. I decided to drop it off at my mechanics for repair.
Aug 16, 2007 at 8:16 AM
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