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Mike V.
Mike V., Auto Service Technician
Category: Car
Satisfied Customers: 25677
Experience:  25 years of experience, Certified Subaru Technician and Nissan factory trained.
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XG350 - 2004 - check engine stayed on, car shook when in drive

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XG350 - 2004 - check engine stayed on, car shook when in drive or reverse; diagnostics - ignition coil arching; batter was replaced; car was tuned up, spark plugs replaced; 4 hrs later - engine light came back on - no shaking - was told I need a catalytic converter- left because warm up code was p0431; vehicle has a misfire and it's possible to damage convertor; if emission test were to be taken, I'd need to have this corrected; otherwise, it's not mandatory - should I get the dealer's opinion?
Greetings Sir or Madam and welcome to JA! I will do my very best to assist you with your problem.
This can cause running problems with the car, however I would first have the code cleared and see if it comes back. When you had the misfire it does dump raw gas in there and that will cause the converter damage.
The dealer can check and make sure the converter is in fact working wrong and not the rear O2 sensor, but honestly, I always clear the codes and see if they come back when it's a converter code.
That is where I would start. Now that the engine is running properly, it may have triggered the code.
I hope this helps!
If you need further assistance, please be sure and let me know, if not, then please be sure to rate my answer.
Thank you.
Customer: replied 4 years ago.

thanks, XXXXX XXXXX you suggesting that the ones who worked on it already clear that p0431 warm up convertor code before I go see the dealer?

or should i just go see the dealer with the info I've already shared with you? Also, are the prices i shared with you for the work done and that which they gave me for the work for the convertor, are those prices about right for this type of problem?

First, yes, I am telling you that they should just clear the code first. Ask them to clear it and then drive the car, if the same code pops back up, then you know that there is in fact a problem.
See, if there was any residual fuel in the converter from the misfire, it could throw that code and then clear up and never throw it again.
If the light comes back with the same code, then it's a safe assumption that the misfire did cause damage to the converter.
The price they are quoting for the converter is accurate.
I need a detailed list of parts that were replaced with the tune up to determine if that cost is relatively accurate, but based on the pricing for the converter you are being quoted, I think they are honest.
Customer: replied 4 years ago.

wireset - 68.80; spark plug - 161.88; ignition coil; 424.02; replace both spark plug banks; 252.45; felpro - intake plenum gasket - 29.78; interstate battery - 138.95; labor - 252.45


so should the transmission people be the ones to clear this code, or should I take it to the dealer, asking him to clear the code first, before doing anything else, as you suggest. thank you for your patience - i'm a senior, who needs someone like you to advise me. thank you so much.

Ok, checking the pricing, labor for the plugs alone is almost 3 hours, the wire set should not have any extra labor charge on it.
$168 for a set of spark plugs seems high unless there is some labor charged added to it.
Not happy with the price of the ignition coil. I am showing the dealer coil to be $89.00
See, I am a little confused with the pricing because the labor I understand at $252, but it looks like they charged you labor for replacing the plugs twice here.

replace both spark plug banks; 252.45; felpro - intake plenum gasket - 29.78; interstate battery - 138.95; labor - 252.45


Anyone can clear the code for you. Trans shop, dealer, that part doesn't matter.

I am thinking the battery price is about right, the intake is about right, and even the labor charge, but I do think you were over charged for the spark plugs and hit very hard for the coil.

Both are over charges to me.


Mike V. and 2 other Car Specialists are ready to help you
Customer: replied 4 years ago.

i'm sorry - the replacing of the spark sparks was 161.88

Customer: replied 4 years ago.

are you gone? if so, I'll rate you - thanks