So I know very little about how these things work. I'm questioning my local dealer service department. I have an 04 F150 with 138,000 miles on it. It burns about a quart of oil every 1000 miles. I've had the die test and it is just burning it.

I took it to the dealer because the check engine light came on. They said the O2 sensor threw it, but the direct cause was the spark plugs and the catalytic converter. That is why it is burning so much oil. The cost to repair was $3750.00. They said the cost of the converter $2800.00 for just the parts. I thought that sounded a bit high. They kept telling me this was a great time to trade the truck in a get a new one.

Any thoughts!!!!

 

Yeah, find another dealer. Your oil consumption has nothing to do with the spark plugs or the catalytic converters, but could be the reason for the MIL. I'd have a muffler shop weld new cats on. Aftermarket cats are waaayyyy cheaper than what they're quoting you. Changing the plugs might not be that easy based on everything I've read on these plugs, especially with that mileage.

 

I'd find another dealer for a second opinion if I was in your shoes. As for trading, only if you want to.

 

I would definitely be looking in to a new dealer. If the cats do turn out to be a problem, look into magnaflow high flow cats, quite a bit cheaper then OEM.

 

What needs to be done first is find out why it's burning so much oil and fix that problem. If you don't then it's going to keep killing O2 sensors and converters. When the oily residue builds up inside the converter it causes it to overheat and burn out. The converters need heat to operate but too much destroys them. The O2 sensors can be ruined by simply using the wrong throttle body cleaner.