Anyone ever have a fuel injector make a knocking or pinging noise? My 88 formula with a 3.4 swap and camaro injectors seems to be pinging from the injector area. With a listening device you can here the noise real good on the injector rail very pronounced noise. Just thought I would throw this out there to see if anyone has had this problem before.

[This message has been edited by indyguy (edited 06-14-2008).]

Try using the search function here on the PFF site for "noisy Injectors"......I recently read some posts where People were talking about exactly what You describe.....I actually searched for "noisy valve train" and got answers I needed but also saw a few posts about the noisy injectors...hope this helps

Injectors aren't all that quiet but the sound is clickity-clickity rather than tap-tap (makes sense right?) The pitch is higher than lifters and rockers.

The injectors click faster than the valve train so they are pretty easy to spot and separate from the other noises.

Yeah I know what you mean about the pitch and sound. It's actually weird if you put your finger on the fuel rail you actually feel a good hard tapping at the rail.

Yeah, all that clicking adds up. I noticed the Multecs seem to be a bit louder.

I use a stethoscope to listen to each one if I think one is hanging up. You can hear the difference in a bad injector pretty quick.

Batch fire injector setups like on the Fiero V6 are much noisier than sequential TPFI. Batch fire means that three injectors are energized all at once each cycle of the crank. You will hear a clicking sound if you put the stethescope on each injector. If you increase displacement and go to larger injectors the sound will be more pronounced as the cycle time will be smaller. Injector noise is normal and not harnful.

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87GT - 3800SC Series III engine, 3.4" Pulley Flotech Exhaust Autolite 104's 4T65eHD
87GT - 3.4L Turbocharged engine, modified TH125H
" I'M ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 06-14-2008).]

My injectors are quite loud and audible over the engine. If I take out some of the interior I can hear them inside the car. I've recently replaced them when my old set was leaking and the noise is the same.

They make a definite Click noise though, very different from knocking or pinging.

Well maybe wish full thinking on my part about the injector noise. I bought this car from 88silverformula he had an engine swap done and had to sell the car cause he was getting married and the engine made that pinging noise. I drove the car 650 miles from Kentucky to Missouri and it ran great the noise does not change regardless of light or heavy oil. It is the same all the time no matter what with the exception being when the engine is really warm it may be a tad less. But I will keep looking and see what I can find. Thanks for all the input so far.

If the car runs O K I would try chevron techron fuel system cleaner..add to 4 or 5 gallons of gas ..Pep boys has this on sale,, buy one get one free untill the close of business today,saturday june 14,2008
Is it one noisier ,,or all ??
the alternative is to pull the rail and check it out
3rd ...send the injectors to cruzin performance ,michigan or Linder tech Indianapolis these companies have been recomended by more than 2 fiero forum members

Noisy injectors are normal even on new cars when the engine is cold,, then they quiet down after 5 to 10 minutes..

[This message has been edited by uhlanstan (edited 06-14-2008).]

The fuel treatment I was going to use was BG fuel injection cleaner 44k I believe it's called. I think this would be stronger than off the shelf injection cleaner. I'll do that tonight and see what happens.

Here is a good example of how loud injectors are when they are in operation- and some good info about the spray patterns different injectors have-
http://www.youtube.com/watch?v=Emnax2J4FX4