Electronic Spark Module ... future MY 90 Achilles Heel? - ZR-1 Net Registry Forums

GOLDCYLON · 02-23-2018

While browsing parts for my cars on EBay I noticed a part there in the mix I never noticed before. I have been driving my 1991 ZR-1 for 12 years now however just over a year ago I bought a 1990 ZR-1. A few of you know that the MY 90 had a few differences technically that did not follow into the different model years as the electronics and the engines for that matter improved. While almost everybody knows about the ECM and the DIS that are failure points along the entire model run I propose that I have stumbled upon a MY 90 potential problem area that I was completely unaware of. While I am fairly knowledgeable about ZR-1s I will be the first to tell you I know several members in the community that have probably forgotten more than I will ever know lol.

The ESC is also called the electronic knock module. It provides an modular interface between the knock sensor and the ECM. On earlier C4s it was located near the evaporator housing and in the 90 ZR-1 it is located on the evaporator suitcase below the radiator high fill point. In 1991 ZR-1s and on later cars ESC was incorporated into the memcal in the ECM. When the ECM detects knock (pre-ignition), it will retard the timing to save the engine from damage. This will sometimes result in a loss of power and pinging and overall poor running conditions. Just like the MY1990 air bag frame rail sensors and the Air Bag DERM module the ESC I believe is a MY 90 ZR-1 LT5 ONLY specific part. I have no idea on availability of this item however I suggest as our cars continue to age that this might be an area of concern. I suggest if you can find one you add it to your parts store if you own a 1990 ZR-1.

I have personally not heard of a failure of the ESC However Usually a Service Engine Code will be thrown if it fails. If it fails "silently" your ECM will not be able to detect any pre-ignition due to bad gas, improper timing, electronic misses etc. and you may damage your engine if not replaced. There is one of these currently on EBay for sale that I advise may be a good item to stock away. Here is that EBay auction number 192441750427. (Not my auction and not affiliated in any way shape or form) just passing along the information.

The GM part number and interchange number is 16080211, D1931A

Just my thoughts your mileage may vary. GC

02-23-2018	#1
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Electronic Spark Module ... future MY 90 Achilles Heel? While browsing parts for my cars on EBay I noticed a part there in the mix I never noticed before. I have been driving my 1991 ZR-1 for 12 years now however just over a year ago I bought a 1990 ZR-1. A few of you know that the MY 90 had a few differences technically that did not follow into the different model years as the electronics and the engines for that matter improved. While almost everybody knows about the ECM and the DIS that are failure points along the entire model run I propose that I have stumbled upon a MY 90 potential problem area that I was completely unaware of. While I am fairly knowledgeable about ZR-1s I will be the first to tell you I know several members in the community that have probably forgotten more than I will ever know lol. The ESC is also called the electronic knock module. It provides an modular interface between the knock sensor and the ECM. On earlier C4s it was located near the evaporator housing and in the 90 ZR-1 it is located on the evaporator suitcase below the radiator high fill point. In 1991 ZR-1s and on later cars ESC was incorporated into the memcal in the ECM. When the ECM detects knock (pre-ignition), it will retard the timing to save the engine from damage. This will sometimes result in a loss of power and pinging and overall poor running conditions. Just like the MY1990 air bag frame rail sensors and the Air Bag DERM module the ESC I believe is a MY 90 ZR-1 LT5 ONLY specific part. I have no idea on availability of this item however I suggest as our cars continue to age that this might be an area of concern. I suggest if you can find one you add it to your parts store if you own a 1990 ZR-1. I have personally not heard of a failure of the ESC However Usually a Service Engine Code will be thrown if it fails. If it fails "silently" your ECM will not be able to detect any pre-ignition due to bad gas, improper timing, electronic misses etc. and you may damage your engine if not replaced. There is one of these currently on EBay for sale that I advise may be a good item to stock away. Here is that EBay auction number 192441750427. (Not my auction and not affiliated in any way shape or form) just passing along the information. The GM part number and interchange number is 16080211, D1931A Just my thoughts your mileage may vary. GC __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by XfireZ51; 02-23-2018 at 11:50 PM.