NOISY FUEL INJECTOR. CAUSES?

[dr-rjp]

I can hear one of my injectors making a loud clicking noise...louder than it should be, I should say.

What needs to be fixed or replaced here?

[Q45tech]

Replace with a brand new injector [with brand new o rings] if the noise bothers you.

[captainluigi]

while replacement with new is always a very good suggestion, there is possibly another solution. appx. 1k miles ago i had the fuel rail flush performed. prior to this the clicking was extremely bothersome to me. i could not hear it in the vehicle but was annoying me to no end. since the flush the clatter is GREATLY reduced. coincidence possibly? no say! dennis what do you think?

[goody90q45]

Other than the clicking how's the engine running? Fuel mileage, smooth idle, acceleration, throttle response?

If you have a digital volt meter and know how to use it it's really easy to ohm your injectors (and knock sensors). It won't take more than 10 minutes. See the link below.

http://www.q45.org/ohminjectors.html

Let us know what your ohm readings are and a brief service history and you'll get lot's of input. Good luck.

[Q45tech]

After about 60- 100,000 miles all injectors get noiser and noiser, however they won't fail from the noise.

With proper gasoline and mainteance [BG44k] they should all last in excess of 300,000 miles.

Early failure just proves you purchased improper* gasoline or didn't perform mainteance correctly.

* Gasoline that varied significantly from that gasoline they were designed to function with in Japan.

[dr-rjp]

while replacement with new is always a very good suggestion, there is possibly another solution. appx. 1k miles ago i had the fuel rail flush performed. prior to this the clicking was extremely bothersome to me. i could not hear it in the vehicle but was annoying me to no end. since the flush the clatter is GREATLY reduced. coincidence possibly? no say! dennis what do you think?

To answer the other question first, my car is running just fine...except for the gas smell when starting up (probably an EGR/EVAP issue). Acceleration is great. Runs smooth. Gas mileage could be a lot better.

So, this is thei first time I have ever heard about a "fuel rail flush." Makes sense to me since we flush out everything else. Now, when a shop does an injector cleaning, I guess that they don't flush out the rails.

Is that right?

Tell me more.

[captainluigi]

use the search feature for fuelrail flush or injector flush. there are threads that will explain much better than i. tell us about your fuel mileage. my 96Q is the ONLY vehicle that continually gives me BETTER than its epa rating. yes you read that correctlky. after 16k miles of ownership and have religiously kept a diligent fuel log (every receipt) 23+mpg mostly hiway & occasionally 24+mpg on longer trips between fl. keys to west coast usa.

[Q45tech]

One must ask as different dealers do differnt things for fuel injector cleaning. Some just dump in BG44k into gas and call it a fuel injection service. Rail flushes take longer and cost $100+. Induction flush is different and can also cost an extra $100.

I like to do all 3 simultaneously/sequentally. Then change the oil after a 10 mle high speed [rpm] blow out the crap test drive.

[dr-rjp]

use the search feature for fuelrail flush or injector flush. there are threads that will explain much better than i. tell us about your fuel mileage. my 96Q is the ONLY vehicle that continually gives me BETTER than its epa rating. yes you read that correctlky. after 16k miles of ownership and have religiously kept a diligent fuel log (every receipt) 23+mpg mostly hiway & occasionally 24+mpg on longer trips between fl. keys to west coast usa.

No doubt! New cars fresh off the truck do not run as well as those that have been broken in. The EPA estimates are not "real-world" estimates, to begin with, and more importantly, they are point estimates; i.e. averages (as in means).

Just like in political polling, there is a margin of error in measuring gas mileage. Yet, you will not find any error estimates to go along with the reported averages. It sure would help to know them.

Like, for example, if an EPA estimated 25mpg had an error margin of 5%, then that would mean about 95% of the new vehicles like the one they tested should have a range of 23.8 to 26.3 mpg.

However, it also means that 5% of the time there will be new cars like the one tested that will get mileage as high as 27mpg, or as low as 23mpg.

Again, these are estimates for new cars with less than 100 miles on them. As for very high mileage cars, the results can also be surprising.

My 1992 Maxima GXE was rated to get 18-19mpg in the city as a new car. After ten years and 300k miles, my Max was still getting 18-19mpg in the city.

The main reason why "used" cars get better gas mileage than brand new is because of all of the friction that exists in new car parts: engine, transmission, drive train,axles, etc..

Sort of like the difference between how you feel when you first wake up in the morning versus how you feel later on in the day. When I wake up in the morning, it is a chore just to be able to walk to the kitchen to make coffee.

[Q45tech]

All EPA MPG type test are done with INDOLENE CLEAR instead of PUMP GASOLINE to avoid the extremely wide variations in sold at the pump gasoline.

This is a very special custom fuel made for car manufacturers to test MPG and engine power output, emission etc.

Unfortunately INDOLENE CLEAR only functions in a narrow 68-80F temperature range so it cannot be used outside the lab.

"It's in smaller print on the label. On a 2006 Ford Explorer 4X4 with V8, for instance, the label states that the city driving range could be as low as 11 mpg and as high as 17 mpg. Meantime, the big, black number on the sticker that catches a shopper's eye says city mpg is 14.

The posted highway mileage for the same Explorer is 20 mpg. But the range, in the small print, says it could be as low as 17 mpg or as high as 23 mpg.

And to be fair, even the biggest fuel economy numbers come with a caveat printed right by them: "Actual mileage may vary with options, driving conditions, driving habits and vehicle's condition."

http://autos.msn.com/advice/ar...23628

[dr-rjp]

..."It's in smaller print on the label. On a 2006 Ford Explorer 4X4 with V8, for instance, the label states that the city driving range could be as low as 11 mpg and as high as 17 mpg. Meantime, the big, black number on the sticker that catches a shopper's eye says city mpg is 14.

The posted highway mileage for the same Explorer is 20 mpg. But the range, in the small print, says it could be as low as 17 mpg or as high as 23 mpg.

So, is it the case that all of their MPG estimates vary by +/- 3mpg, or are your two examples merely a coincidence with respect to how much they vary?

The reason I ask is because +/-3mpg with a 14mpg average is a 21% error margin, whereas +/-3mpg with a 20mpg average is a 15% error margin.

Something does not seem right here.