I just finished up the GM big block 2bbl install and the injectors are very loud... sounds like a high frequency screaming noise... not the normal quiet ticking noise.
Any ideas what could be wrong?

 

whats your pressure? have the injectors been sitting a long time?

 

Dan,

What control system are you using? New/older ECM? Aftermarket DFI?

The injectors should only click or tick at low RPMs. You might be hearing the fuel and air whistling past the almost closed throttle plates, or a scream from the IAC.

Just guessing...

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

I haven't checked the pressure yet but its not running rich.

I bought the TBI unit used and have no idea how long it had been sitting.

I'm running a 747 ecm. The chip is stock with the exception of a BPW change and the EGR turned off.

This is not your standard ticking noise. Sounds kind of like my buddies procharger at idle but about twice as loud and a bit higher frequency. Ear piercing.

I verified that its not the IAC and I'm pretty sure its not air through the throttle blades. I'm 99% sure its the injectors making the noise.

Has anyone heard injectors make a loud screaming noise? Does this happen if they have been sitting for a long time?

I have another set of injectors from the stock TBI unit. I can try them with a BPW change but they have been sitting for 2-3 years.

I'm planning on installing a FP gauge but havent gotten around to it yet. I do have a high volume pump (255lph) so it is possible that it could be overloading the regulator or the return line but again its not running rich... besides I've heard of others running lots o pressure with these GM injectors and have never heard of these problems.
Think it could be pressure related?

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1988 T/A,
9" Ford, 3.50 gears, Auburn posi, 700r4 -w- 2100 converter, 360ci, 9.8:1 cr,
AFR 195 Heads, Weiand #7525 intake, Lunati roller 219/227, .479/.480, 112 LSA
GM big block 2bbl TBI on truck 7747 computer

 

I'll bet four nickels that it's not the injectors.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

come to think of it, i had a super loud high pitched whistle one time. it was because the throttle body to manifold gasket was stickin out into the bores and cutting the air as it was going thru, only at specific rpms though.