Sputtering Deville

When it drives, does the engine run mostly normal? It could be the firing meck itself getting a bit worn and maybe showing it's age a bit. Last Caddy I used was a 1984 so I am just guessing, that ones engine blew totaly on me.

Cal wrote: C>I've got a 1999 Deville with 135,000 miles. In the last couple of weeks it C>just started to misfire occasionally. It has new sparkplugs about 20,000 C>miles ago. Still has original plug wires which I'm suspecting... or maybe a C>fuel injector??? Gas mileage doesn't seem to be affected. C>

C>Any other ideas that I may be missing?

You are on the right track; after 100Kmi the plug wires should be routinely replaced. An easy check would be to have the engine running, and in total darkness, spray a mist of water over the wires. You might see some miniature lightning under the hood.

BTW, misfires generally set a DTC, and I believe you can pull them to view. Try pressing and holding the [Off] and [Passenger Warmer] buttons on the Climate Control panel simultaneously until all tell-tale lights in front of you illuminate; then watch the DIC as the DTCs are displayed, current or history. It will start with PCM. Exit by pushing in the big A/C Temp dial button, or by turning the ignition off.

You're due for wires anyway. After 8 years and 135K miles you got your moneys worth out of those originals. I'd start there. FWIW YMMV

Thanks for the info... actually the only code I got was PZM Bo533 which I think is referring to a short in the Fuel Sensor... is the sensor easy to get at and easily replaced?

I've got a 144k mile and at about the 135k mark the same thing happened to me. I bought the expensive platenium plugs and wires an the problem is gone!

Skip