ZR-1 Net Registry Forums  

Go Back   ZR-1 Net Registry Forums > C4 ZR-1 > C4 ZR-1 Technical Postings

 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 06-22-2020   #10
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,698
Default Re: ECM Issues - No Start

Quote:
Originally Posted by Macroblock View Post
Awesome!

Verifying that the injectors are working is actually straightforward. Remove the Yellow or Gray 22-way Connector to the ECM. Turn the key to ON. One at a time, jump a wire from the (-) Battery Post to positions 1, 2, 3, 7, 8 12, 13 and 18 on the Connector. An injector that makes an audible click, is likely OK.

The injectors used in the early years of the ZR1 are susceptible to damage from ethanol in the fuel (not normally found in premium blends). The injectors develop shorts within their respective solenoid windings. Bad injectors will not produce a healthy click (a totally failed injector will not click). A current measurement can be used to verify the health status of an injector but the simple 'click' test provides discernible results.

Verifying the ECM is sending a (-) signal to each injector, without pulling the plenum, involves opening the ECM and ---CAREFULLY---checking each DRAIN PIN on the 8 Power MOSFETS. Use a 12 volt test light connected to (+) post of the battery. Have a friend turn the engine over (not literally). The test light should blink for each transistor. The ECM PC Board is marked "D" to guide you.

It is also possible to skin some of the jackets on the wires that feed the injectors and utilize a 12v test light, but by doing this you damage the wiring. To repair, coat the bare copper with heated solder and while still hot apply vinyl electrical tape.

In the case at hand, the ECM is unfortunately at fault. It looks like I.C. Component number U13 has failed (Sequential Injection Controller). As a result, only Injector 6 gets a (-) signal from the ECM.
Used this procedure today to check injector pulsing. Worked well. It may have helped w a knock issue I have been pursuing for some time, but not sure if this was what solved it for me or not.
__________________
[SIGPIC][/SIGPIC]Former Membership Chairman
Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
XfireZ51 is offline   Reply With Quote
 


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:27 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright ZR-1 Net Registry 2020