[jcalpert]

Every time I step on the gas now my 02 SLS hesistates and bucks. The problem started about two weeks ago. I replaced the air filter and tried premium grade fuel. The car has 65K miles. Any thoughts on what the problem might be please? Thanks.

 

[mcowden]

Every time I step on the gas now my 02 SLS hesistates and bucks. The problem started about two weeks ago. I replaced the air filter and tried premium grade fuel. The car has 65K miles. Any thoughts on what the problem might be please? Thanks.

Is it hard to start, especially when hot?

 

[sjwoodruff]

Sounds like classic example of arcing spark plug wire(s). I'd be willing to bet you need new wires. If that's the case, you'll probably want to replace plugs too, as your'll have access to them at that point.

 

[jcalpert]

No problem starting, cold or hot.

 

[jcalpert]

Thanks for the advice on the wires and plugs. I'll give that a try. They are probably due to be done anyway.

 

[jcalpert]

No problem starting cold or hot.

 

[sjwoodruff]

Thanks for the advice on the wires and plugs. I'll give that a try. They are probably due to be done anyway.

It seems a little early, with the low miles and model year, but a possibility nonetheless. It's an easy do-it-yourselfer, but a shop will charge you a bunch. Stay OEM with the plugs and wires for best results. They aren't cheap - plugs are about $5.50 each and the wires will probably be around $100 or more...can't remember what I spent. Big difference though, and my fuel economy went up about 1.5 mpg on long highway trips.

I'd check your diagnostic codes to see if the car is trying to tell you something before doing anything. The plugs and wires should last to about 100K, but sometimes things fail early and in this case it only takes one bad wire to ruin the way the engine runs.

 

[mcowden]

Sounds like classic example of arcing spark plug wire(s). I'd be willing to bet you need new wires. If that's the case, you'll probably want to replace plugs too, as your'll have access to them at that point.

On 2000's and above, they use Coil-On-Plug (COP), so there are no high voltage wires because the coil is sitting right on top of the plug. If a coil was bad, I think you'd get a miss at all speeds. Same thing for a plug problem. If a plug was fouled, you'd have a more consistent miss. It doesn't sound like an ignition problem to me, unless it's an ignition problem caused by a failing sensor. Maybe a TPS or CKP? Fuel pressure regulator?

Does the car have any other problems? Have you checked for codes yet? Go here:

http://www.cadillacforums.com/forums/showthread.php?t=53635