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Oct 24, 2013 | 05:12 PM

iamjeff

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8th Gear

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94 starting issues

I have a 94 that the opti was changed 4 months ago. It has spark, 42 psi fuel and the injectors are pulsing.
Codes I pulled are (1) h31 to 38 (4) 41 (9) h42
It was running perfect then suddenly wouldn't start.
It did have a bad battery that i am guessing are from the h codes

Any body else have an idea?

Oct 24, 2013 | 10:51 PM

1993C4LT1

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From: Dallas Texas

2025 C4 of the Year Finalist - Modified

Could be the ICM?

Oct 24, 2013 | 11:02 PM

iamjeff

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If the icm is at fault would the injectors still fire?

Oct 25, 2013 | 03:39 PM

ToniJ1960

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From: Granite City Illinois

Ok I dont know a lot about this so dont get upset if I just offer a suggestion.

Maybe pull a plug and see if theres any gas smell on it or in the cylinder?

Oct 25, 2013 | 05:28 PM

Kevova

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From: near the thumb in the mitten

If ICM is bad normally you will lose spark and/or pulse. Your car SFI the dtc 41 maybe the key. Injectors fire one at a time in firing order, if they are not in sync engine wont start. Weak dead battery will need to be replaced or charged, low voltage(>10.5v) causes modules to make mistakes. Check grounds. Do you have FSM?

Oct 25, 2013 | 11:47 PM

vetteoz

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Quote:

Originally Posted by iamjeff

ICodes I pulled are (1) h31 to 38 (4) 41 (9) h42

Your in trouble
DTC 41 in the module 4 ( the ECM ) loss of serial data from the CCM to the ECM.
If the ECM does not get the signal from the CCM on that circuit to fire the injectors, the engine won't fire
A very hard to identify problem.
Multiple potential causes , bad connection(s) , bad grounds , faulty CCM

Start here
http://forums.corvetteforum.com/1554492041-post15.html
http://www.digitalcorvettes.com/foru...5&postcount=17
http://forums.corvetteforum.com/1554993058-post25.html
http://forums.corvetteforum.com/1555985163-post33.html
http://forums.corvetteforum.com/c4-t...wes-is-me.html

FWIW
31 - 38 in module 1 ( the CCM ) are all (H = past ) data circuit related faults so maybe you are lucky and only have a faulty CCM.

Last edited by vetteoz; Oct 25, 2013 at 11:50 PM.

Oct 27, 2013 | 02:18 PM

iamjeff

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I do have a fsm and i am trying to trace the ground issue, atleast i am hoping thats it

Oct 27, 2013 | 10:40 PM

desertmike1

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From: Palmdale CA

It looks like you have an ECM (4) code 41

DTC 41 - Ignition Control (IC) Circuit (Open Circuit) - See more at: http://tech.corvettecentral.com/2011....7yLrzUBa.dpuf

This is an old training film but comes in handy.. pay attention to [14:35]

http://www.youtube.com/watch?v=lFCja...ature=youtu.be

I would clear all codes and try a start up.. if you go to DTC41 in the FSM it will give a fault tree for further trouble shooting.

Not sure what all you had to do with your weak battery, but if you did any "Jumping" this could have played havic with your electrical system.