Check Engine Light?

[manitou_commando]

My 1998 318ti, w/64,000m had the check engine light come on a little over a year ago. So I took it to Advance a month ago 'casuse I had a little time on my hands, to have it checked out. They came back with two codes: catalytic converter and cam sensor. By the way, the car runs fine and gets 33mpg, so it seems like nothing is particularly troubling, just the light.
I had them reset the system and the light came back on a couple weeks later. Called Midas, who wants between $48 and $96 to diagnose the emissions.
Question to the group: is there a way to go about this methodically? Is one scenario more likely than another?

[cooljess76]

ummm, replace catalytic converter and cam sensor. Remanufactured cats run about 1400 bucks at the dealer. If money's tight, try to find a used catalytic converter on the forum. It's illegal for junkyards to sell them and aftermarket cats don't work. Might want to purchase new nuts and bolts before you remove the old cat as the old studs tend to snap. Cam sensor might be a one-time old code that was stored in your ECU, you should get the codes read again now that the light came back on.

[AquaCali]

If the code for the cam positon sensor comes back, replace it. The cam position sensor is $123 + o-ring at the dealer, BAV sells it for $96 + o-ring. I had to replace mine last week got the CEL for it twice and then it failed. When it fails the car will not run. So you might want to due a little prenventive maintaince beforehand. If you have small hands and know the layout for the connector it can be done with only removing the throttle body, otherwise the upper portion of the intake manifold has to come off.

[L84THSKY]

I have a 1998 318ti too. I've had to replace both those items, so they both are most likely legitimate concerns.

Originally Posted by manitou_commando

My 1998 318ti, w/64,000m had the check engine light come on a little over a year ago. So I took it to Advance a month ago 'casuse I had a little time on my hands, to have it checked out. They came back with two codes: catalytic converter and cam sensor. By the way, the car runs fine and gets 33mpg, so it seems like nothing is particularly troubling, just the light.
I had them reset the system and the light came back on a couple weeks later. Called Midas, who wants between $48 and $96 to diagnose the emissions.
Question to the group: is there a way to go about this methodically? Is one scenario more likely than another?

[manitou_commando]

Thanks for the input, fellow owners. This is how I'll proceed: go back to Advance and have codes read again. If the cam sensor comes up, that'sll be the first thing to get replaced. Then proceed to the cat.
I just find it bazaar that a car w/only 64K miles would have a cat that fails. Might it be O2 sensors and not the cat? Is there a way to diagnose?

[pnosker]

1998 cats were recalled and the recall lasted till 2008 for free from the dealership. You might be able to get them to still honor it.

[b.u.ti-ful]

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