# Fuel injectors replacement



## kiev95 (Jul 28, 2004)

Hello,

My car is messed up. First I got misfire on cylender 5. Took it to the dealer, who told me that i need to replace fuel injector on cylinder 5. Does anyone know where i can find information on how to replace fuel injectors?


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## seximagtr (Feb 22, 2003)

kiev95 said:


> Hello,
> 
> My car is messed up. First I got misfire on cylender 5. Took it to the dealer, who told me that i need to replace fuel injector on cylinder 5. Does anyone know where i can find information on how to replace fuel injectors?


1) Purge fuel lines of any fuel by removing fuse/ cranking
2) remove upper intake plenum
3) unplug electrical connectors/ remove screws
4) Pull REALLY hard and pop the injector off - maybe use a thing flathead to help pry... done... tada!


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## alexnds (Oct 1, 2005)

*pulling out fuel injectors*



seximagtr said:


> 1) Purge fuel lines of any fuel by removing fuse/ cranking
> 2) remove upper intake plenum
> 3) unplug electrical connectors/ remove screws
> 4) Pull REALLY hard and pop the injector off - maybe use a thing flathead to help pry... done... tada!


I have the exact same problem! Is this something that a handy Do IT yourself can do? If I simply pull out the fuse to the fuel pump, doesn't that stop the fuel from moving ? (I know how to remove the air intake plenum). Can you recommend a source of good rebuilt injectors. The Nissan OEM's are $125 a pop, plus $2 for the O-rings, so all together, it's over $800 in parts for all 6 injectors. 

Also, what do you think of this site:

Sonic Cleaning of Fuel Injectors
http://www.accurateis.com/

That is, cleaning them rather than replacing them, if they are not totally fouled up? 

Also, what is a test of a injector being bad? Different number of ohms for that injector vs other injectors? Any help highly, highly appreciated.


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## WitchHunter (Jan 25, 2005)

The injectors are usually difficult to remove from the rail, but it can be done.
I don't suggest prying them with a screwdriver, as that can damage them. We often get them in for servicing and they are broken due to prying them out.
We find it easiest to first rotate them to help break them free then remove the rail and press them out from the bottom.
I suggest that you send your injectors out to be checked and professionally cleaned and replace any that are bad. 
The coils are the problem with this type of injector. Check each coils resistance with a digital meter and verify that it is about 10 - 12 ohms. Bad ones will be higher.

Gordon
WitchHunter Performance 
Fuel Injector Cleaning & Flow testing service


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## alexnds (Oct 1, 2005)

*Injector cleaning service*

Thank you so much for replying! You can't believe how much research I had to do to find out about "sonic cleaning" of injectors vs rebuilt injectors, vs new injectors. It in fact, is not common knowledge and I think a little knowledge goes along way. I read your web site as well and I'm extremely glad a company like yours exists in the first place!

The numbers are something around these figures for my VG30E Maxima:
New injectors, from the dealer, OEM, with O-rings (which are only $2 bucks)
is $125 per injector. So all about $800 or so. So called "rebuilt injectors" are about $400 for a set of 6. Used injectors, from a junkyard car, are not easy to find. 

I'm keeping the injectors in the motor. Instead, I'm getting a used set from a friend that has upgraded his injectors to higher flow injectors, because he installed a turbo. Thus, he no longer needed his stock injectors. The stock injectors he's selling me are from a car with 100k miles on it. Instead of swapping them in right away, I will send them for sonic cleaning and to even out the fuel flow amongst them. I will then pull out the ones in the motor (146k mile motor, with one bad injector) and install the cleaned ones from the 100k motor. 

The Nissan Dealer identified one injector at 17 ohms and the rest much less, but because the labor involved is the same whether I replaced one, or replaced all, so the dealer, quite logically, recommended replacing all. However, the total labor cost and part cost id $1300, a big number considering how old the car is. Without a service like your company offers, little guys like me would not be in good shape.

As soon as I receive the used injectors from the 100k Motor, I will send you a private PM. Upon the original injectors from the 146k motor being pulled out, provided they're not damaged, I will send these too you as well, for them to get cleaned up, so I will at least have 5 out 6 "standby" injectors.

Again, I'm exceptionally pleased that a company like yours is around and provides this service. The cost of the service in relationship to the total dollars involved, as I mentioned above, is more than reasonable. I hope others will read this post and will see the benefits of what I underwent, and will apply it to their own situation. Thanks again in advance.


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## N1ssanmax1 (Aug 1, 2005)

are you sure itis a fuel injector? i have a missfire and i was told it was a coil problem. Im new at this whole thing with the nissan. But if your not 100% sure it is your injectors the coils are shit in those cars too.

But like I said Im new.......just an idea


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## DRUNKHORSE (Mar 6, 2005)

The coils are known to go out on the 99's. If you think its the fuel injector check it by turning the car on then disconnect the electrical connector from the injector you think is faulty. If the injector is working properly, once you disconnect the electrical connector you will notice the poor performance right away. If there is no difference, start off by checking its ground. Then check voltage with a "noid light", if the injector is getting proper voltage then take the injector out and check if its opening and closing right. here an example of how it might look







except, it should be more of a cone spray than a drip. Finally here are some links to, how to replace the injectors, and to check the coils.Link #1, Link #2, Link #3 (how to check the coils)


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## Elteec (Oct 1, 2020)

I have a 2008 Frontier V6 4.0 engine. My check engine light did not come on, but I put on the ODB2 just checking. The truck is running great. No stalling, rough idling, etc. However, it say #2 cylinder I’d misfiring. I guess the best thing to do is disconnect #2 injector to see if there’s a difference in performance idling. Is there anything else simple I could check? I know I can check spark plugs although it’s a pain in the rear. Any advice would be appreciated.


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## rogoman (Dec 16, 2004)

Elteec said:


> I have a 2008 Frontier V6 4.0 engine. My check engine light did not come on, but I put on the ODB2 just checking. The truck is running great. No stalling, rough idling, etc. However, it say #2 cylinder I’d misfiring. I guess the best thing to do is disconnect #2 injector to see if there’s a difference in performance idling. Is there anything else simple I could check? I know I can check spark plugs although it’s a pain in the rear. Any advice would be appreciated.


Here are several causes that could result in a cylinder misfire condition:
Improper spark plug
Insufficient compression
Incorrect fuel pressure
The fuel injector is open or shorted
Bad fuel injector
Intake air leak
The ignition signal circuit is open or shorted
Lack of fuel
Dirty signal plate on camshaft


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