How are Engine Knocks Reported by the Fiero ALDL Data Stream (Page 2/2)
reinhart JUL 25, 05:15 AM
If you just want to monitor if the engine is knocking without there begin any changes to the timing, you could just bypass the computer with a wire to the ALDL connector area and using some sort of light or counter on the dash. The knock sensor is usually just a signal wire that grounds during a knock as the sensor shakes and goes ground to block. If you just had a light, it would be a rather easy setup.just choosing the location of the sensor would be the only question.

If you actually wanted to have your timing adjust, I believe the 85 Fiero ECM can handle it as I know that ECM can handle a turbo setup which is very knock sensitive. You would need a custom Chip of course.
Dennis LaGrua JUL 25, 05:09 PM
If you add a knock sensor there are plans online to build a sound amplifier that will attach to it. using a set of headphones you can hear any knock. Knock sensor hook up to headphones.
Listen to the knock

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 07-25-2022).]

Romsk JUL 25, 06:28 PM
Reinhart and Dennis LaGrua,

Thanks!
I am going to mount 3 raw piezoelectric transducers to the block (one in each axis) and process the signals in my code. Listening for a knock with headphones is a nice idea, but I want to use an Arduino DUE to find knock signatures and light a "Knock" light on the dashboard. The light will also be sent to an unused pin on the Fiero ALDL connector so my ALDL adapter can monitor and display the knocks vs. RPM. I am about to release V1.6.0 of my Fiero GT ALDL Monitor tool on my website: paul.romsky.com. Don't download V 1.5.0, the V 1.6.0 GUI works a lot better and my new Adapter based on the Adafruit Trinket M0 will work better and is cheaper than my previous adapters.

Thanks to all!

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Paul Romsky

[This message has been edited by Romsk (edited 07-25-2022).]