2002 Nissan Altima

Hi I need help again. Flash foward 6 months and I had the motor replaced 3600. I got my car back 4 weeks ago. The motor as 84,000 miles on it. It ran great…I mean better than I ever remember. Well I checked the oil every 3 days. Im obsessive about it. Two weeks ago it was 2 qts low, I filled it up. 3 days later it was 2 qts low again, and the oil was black, After the 3rd time I called the shop I said it’s not leaking or burning oil What is going on, and I think the car is hot, no the gage isn’t moving I just think it’s hot. Took it up Friday and he said it’s the cadilac converter??? Thats where all the oil is going and it’s going to cost 1500 dollars, I like to fell down, I spent all my money on the motor. I know I know I have learned to never love a machine…He said it will blow the motor if I don’t fix it. Sunday driving on the hwy it just died…died,no power, now the battery light came on about 30 min before it died. I had it towed to the shop,but I fear thats the issue if I didn’t blow the motor again It wouldn’t start and I had limited power. So my question is. Shouldn’t have they looked at the cadilac converter? Is the problem with the new motor? Is the responsiblity his? Thanks

You mean ‘catalytic’ converter? That’s part of the exhaust system. That’s not where the oil is going. You may very well have on oil leak or perhaps oil is burning. Did they use a used engine or a certified rebuilt engine? Do you have a warranty on that work done?
The catalytic converter is an emission device. It makes sure you don’t pollute too much. It may run rich (use more gas) or run lean (opposite) but unless that thing is blocked, it usually does not affect the way the car drives. Your mechanic may just be looking to fund his screwup by telling you it is the CAT.
A blocked catalytic converter can do real damage to your car. It if is indeed the CAT, your mechanic should have checked for that when the first engine blew.

If the battery light came on and the car eventually died, it likely is the alternator or maybe the alternator belt. It could also be a bad connection. That’s not why your oil is disappearing, though.

I hate to say this but this model and year is not without its problems. I think the engine is particular for that one year and it has known issues with head gaskets. My sister in law had the very same car with very similar issues.

So it’s not possible for that to clog up in 2 weeks and do that kind of damage? They put a used engine in. I have a 90 day warrenty. There also was a belt screaming. Ok he just called and said it’s the alternator, another 400 buck, he also said the converter is going to have to be fixed if anything the cone has to come out.

A cat does not cause oil loss. @RemcoW is correct that the cat is a emissions device. A clogged cat will cause the car to run like crap and not accelerate. Make him find the oil leak. If it is bypassing the piston rings it could kill the cat, but that is still his problem. As far as the alternator squeal, that could be the belt. This guy sounds shady to me.

You mean “core”, I take it - not cone.
That means he’ll tear whatever is in there out. You likely won’t be able to pass emissions with it. In some states, it is highly illegal to drive without a catalytic converter. What state are you in?

No, that sort of clogging up happens over time - not two weeks. It is often the cause for the engine blowing up in the first place: An engine breathes out through its exhaust. If it is blocked, the built up pressure often finds another way to relieve itself: through the gaskets. Nissan Altimas of your vintage are actually known to have this issue. They are the first of a new series so had some problems.

FWIW, that ‘belt screaming’ could have been your alternator belt. If that thing finally broke, it would cause what you are describing with the car dying, nor charging. A bad alternator also would do this but a bad belt would definitely do this. This is after the fact, but the alternator could be perfectly fine and all it may need is a new belt.

I don’t want to put you up to anything but are you sure that mechanic is treating you alright? Has he always treated you well? With him de-coring the cat, not checking for a blocked cat, the car burning/using oil now and this alternator business, I’m not sure…

Im in KY I know it’s just doesn’t make sense. I questioned him twice about it. He said thats something they wouldn’t have checked when they put the motor in, so maybe that blew the first motor, but why did this one run great for two weeks. He said its part of the exhaust and he would check that. he did say that it’s 1200 degrees and should be 500 I don’t know he come highly recommended, has done some awesome work for people I know. The altimas do have issues to begin with. So whats the down side to having the core beaten out. Hes not doing it, I have to get someone on the side to do it. lol

Okay, just beware that you may be breaking the law by driving without a CAT. You may need to get it fixed at some point, if you need to pass emission.

The oil use is a bit much. I’d get him to fix that.

Okay, just beware that you may be breaking the law by driving without a CAT. -

Change that to you WILL be breaking the law driving without a CAT…and the fines are very hefty.

Sounds good - thanks for being the voice of reason, Mike. :slight_smile:


IMO . . . it sounds like your mechanic is either incompetent, or he’s taking advantage of you

$3600 seems very high for a 84K 11 year old Altima 4-banger motor

Is it possible the mechanic did only very simple repairs for your friends, but he can’t handle the big stuff?

Hi Im back,Again…I have figured out that you can’t love a car…So here I am Oct 9, I have replace the alternator, 400+, I also have no heat unless I push on the gas, he tells me the air conditioner is leaking,humm wasn’t before,and my power stering is whinning,the hoses are leaking he says,(the man that replaced my motor) that wasn’t leaking before either…So anyway yesterday I took it 135 mile trip and it was bogging down, and making a terrible noise, wouldn’t excellerate, had it checked by a mechanic in Indiana, he says it the converter, theres actually 3 of them at 400 each oh my god, I explained to him everything and he said the oil thats disappering out of the motor is whats clogging the converter…what do you all think,…I am so disgustied with this whole thing…I have no more money to put into this car…We had tp rent a car, came back and picked my car up later, it drove fine…We brought it back home. Going to see the man that replaced the motor Saturday…Ideas please!!!

I hate to weigh in on this one except to say that you should not use the word “new” when referring to a used engine with 84k miles on it. It’s well used.

Based on the heavy oil consumption, it’s pointless to consider converter and O2 repairs, alternators, and so on.

I don’t know the original motor exchange transaction was handled but a shop should warn anyone wanting a used engine about the pitfalls that may exist with doing so and use emphasis that when the car leaves the shop any warranty on the engine itself is non-existent.
With used engines/transmissions/etc warranty is generally limited to the labor involved; not the actual part and that’s the way it should be.

? U left car at shop and they said cats were/are bad? They did nothing, and car runs fine now? You drove it home?

Yes it sat there for about 4 hours I couldn’t afford the repair bill and I would rather take it to the home guy who put the motor in

Why was motor changed? Pretty drastic repair.

I have all thats been done to the car if you read my other posts, it’s a long story

You are getting so many opinions about your car and what is wrong with it that I wouldn’t know who to believe or trust. If indeed you have all these problems happening, my advice: junk the car, trade it in, or sell it, if possible. Cut your losses now. Money I’m sure is tight, but it sounds like you’re throwing good money (whatever little you have) after bad. Good luck.

With an oil consumption issue like this it’s pointless to fret over converters, O2 sensors, power steering leaks, or much of anything else.

My suggestion is to check the oil in a 100 miles (maybe even less) and if the oil level is dropping fast then you’re faced with an engine problem.

For what it’s worth, an engine can appear to run fine and still be an oil burner. It’s a used engine (NOT a new one) and any warranty about who does what may be subject to interpretation.

Most mechanics guarantee the installation labor; not the engine/transmission/whatever. The parts themselves are often a coin flip as to whether they’re any good or not.