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Mike V.
Mike V., Infiniti Mechanic
Category: Infiniti
Satisfied Customers: 25192
Experience:  Factory trained to repair Nissan and Subaru.
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2000 Infiniti I30...4 yrs ago I replace injector #1....the

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2000 Infiniti I30...4 yrs ago I replace injector #1....the next year I replaced the rest. Now #1 needs to be replaced again. Should I replace the rest too even though it will cost me $800 more?
Hello and thank you for your question today!
There is no reason to replace all the injectors if only one is failing. Also, they don't fail to often on these cars either.
You should be fine, if you are looking to save a little bit of labor for the future, then have 1,3 and 5 replaced since the upper intake has to come off to do it.
I would not replace all of them however.
Hope this helps!
Please be sure to let me know if you need further assistance. If not, please be sure to rate my answer. If you used the free trial, a rating is still required,you card will not be charged. Thank You!

Customer: replied 4 years ago.

Thank you for that answer. But does the 3 to 4 year period sound reasonable time period for injectors to top working?

Not at all, it's very unusual for this to happen. My 02 maxi has all the original injectors in it. If you have a misfire on that cylinder, make sure they checked the engine compression on that cylinder.I assume they have already swapped the ignition coil to make sure it's not a coil problem.But you should make sure they did. A decent shop would have already run the tests I assume to be 100% sure it's the problem.

Customer: replied 4 years ago.

Before spending almost $1300 I'm trying to cover all bases.


Check engine light came on. AutoZone ran test ... P0301......#1 cylinder misfire...probable cause..fuel sytem malfunction, ignition system fault, large vacuum leak, engine mechanical condition


Mechanic says #1 cylinder is bad and the sensors need replacing too.


Sound like the right diagnosis and solution?

Ummm, no.
First,I would like to know what he means by bad?
I would also like to know what sensors he is saying need to be replaced.
Typically you would have other codes for the sensors.
Customer: replied 4 years ago.

O2 sensor

I was told since the coil was misfiring and the sensor had to work harder. Gas not getting to the engine.

Ok, first, if the coil isn't working, then it needs a coil.
I see no reason at all to replace one of the 4 O2 sensors as it will not cause the problem. The sensor doesn't work harder, all it does is read the exhaust gas. There is no "work" involved for the O2 sensors. They read the exhaust and send a signal to the computer. The computer then creates the fuel mixture.
If the sensor was bad, there would be more then one cylinder misfiring if it were the cause.
If the coil is misfiring, there is no reason that I can see to replace the sensors or the injector. If it's the coil, they should just replace the coil to resolve the problem.

Customer: replied 4 years ago.

Just talked to mechanic ...told injector had internal short. Sensors not working.

ok, I am confused, what's the deal with the coil misfiring?

Customer: replied 4 years ago.

Don't know. I was told the injector has an internal short and that was casuing the misfiring. My car wa running like a truck.. I may be using the wrong terms.


I had the sensors replaced 7 yrs ago.

Ok, here is what I would do if it were my car.
Replace the fuel injector if it's shorted and then have them clear the codes and drive the car.
The O2 sensor would normally give you some type of code, so I would hold off on it and see if there are more issues with it. It may be messed up because of the raw fuel due to the misfire. So, you could start with the injector then take it from there.

Customer: replied 4 years ago.

Thank you for this info. Just talked to mechanic again. I was told the technician used some tool / machine that was checking the engine. In that checking the 02 sensors were not switching. They were not working.

Ok, so all 4 of these sensors aren't switching?
I understand that you can read the sensors with a scan tool.
Customer: replied 4 years ago.

I believe just 2 sensors.

If the sensors aren't switching, then it's possible they are bad. However, I would have them replace the injector that is misfiring and then take it from there. Since I am not sure which ones aren't switching then it's possible the misfire is causing the sensor issue. If the mix it constantly to lean or to rich, the sensors won't switch.

Customer: replied 4 years ago.

Got it!!!! Thank you for all of your help.

YOu are very welcome, if you haven't yet, please be sure to rate one of my answers!
Thanks so much
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