LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

ignition coil

Old May 18, 2015 | 08:17 PM
  #16  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Re: ignition coil

There are 2 fuel injector fuses, each with 4 injectors on the circuit. A short, to ground in the wiring to the pink wire in each injector harness connector, or a short in an injector will blow the fuse. Key on, engine off, connector off injector, check for 12 V on the pink wire in each connector, measured to a good ground. Set meter to ohms and meaure the resistance across the two pins in each injector. Should measure 12-15 ohms.

The injector fuses don't have anything else on the circuit.... not the same fuse as the MAF sensor.
Old May 19, 2015 | 01:10 PM
  #17  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

#10 injector fuse blown again, going to test in morning when I get off work. Which bank of injectors does it supply, drivers or passenger side?
Old May 19, 2015 | 02:01 PM
  #18  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Re: ignition coil

I may have misled you.... I know my 94 has two injector fuses (9 & 10). I have a 96 factory manual, not the 97 and the 96 shows only fuse #9 supplying all 8 injectors. Looking at the 97 Owner's Manual .pdf, page 6-72 confirms fuse #9.

The 96 factory service manual shows fuse #10 is for the engine sensors, including the O2 sensors, skip shift and reverse lockout solenoids, and the MAF sensor.
Old May 20, 2015 | 12:43 AM
  #19  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

Mine has 2 fuses labeled injector. I will look in the morning and verify the fuse numbers.
Old May 20, 2015 | 06:59 AM
  #20  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

It shows on the identification area #9 and 10 are labeled as injector. 10 is the one that keeps blowing. Car won't crank but if I replace it it starts right up.
Old May 20, 2015 | 08:14 AM
  #21  
timnfxr's Avatar
Registered User
 
Joined: May 2012
Posts: 214
From: Long Island, NY
Re: ignition coil

F10 is hot with ignition switch in the run position. Does the fuse blow with key on/engine off? As a start, try disconnecting the sensors involved (MAF,O2, skip shift, and reverse lockout), or one at a time starting with the MAF (easiest to get at).

If you can isolate it without the engine running, no codes should be set for the disconnected sensors.

Good luck.
Old May 20, 2015 | 08:51 AM
  #22  
maybe2fast's Avatar
Registered User
 
Joined: Nov 2006
Posts: 889
From: Commerce, MI
Re: ignition coil

keep us updated
Old May 20, 2015 | 01:17 PM
  #23  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Re: ignition coil

Originally Posted by markzzzz
It shows on the identification area #9 and 10 are labeled as injector. 10 is the one that keeps blowing. Car won't crank but if I replace it it starts right up.
Which fuse is labeled "ENG SENSORS"?

Would appear that both the factory service manual and the Owner's Manual are incorrect.
Old May 21, 2015 | 01:54 PM
  #24  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

Won't have a chance to look at it until Friday morning. Stand by for results then. Thanks for your help.
Old May 22, 2015 | 02:03 PM
  #25  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

Armed with a new actron code scanner I started working on this again. Got 12 volts on the maf sensor. Wouldn't start until I jumped it off. Let it idle for about 20 minutes ran perfect. Then it cut off and gave code p0372 timing reference high resolution signal a too few pulses. I'mready for the bad news. Optispark?
Old May 22, 2015 | 02:32 PM
  #26  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

Another thing that is really bothering me is the fact that it seems to start right up when cold when getting jumped off but not on its own. Battery tests good and alternator tests good (advance auto and O'Reilly, 2 times each). Would a bad battery cause the opti to malfunction at any time? Only getting 13.7 volts at battery when sitting at idle.
Old May 23, 2015 | 12:51 PM
  #27  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

I feel abandoned
Old May 23, 2015 | 01:13 PM
  #28  
moparman's Avatar
Registered User
 
Joined: Nov 1998
Posts: 2,761
From: Louisville, KY
Re: ignition coil

The PO372 is a code for the opti. Check all wiring and connections having to do with the opti harness.

This is a holiday weekend, and a lot of people probably are doing other things.
Old May 23, 2015 | 01:33 PM
  #29  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

I know. I was joking.
Old May 31, 2015 | 01:26 PM
  #30  
markzzzz's Avatar
Thread Starter
Registered User
 
Joined: May 2015
Posts: 30
Re: ignition coil

I decided to change the optispark with a Delphi one that I had as a spare. I took the one that I had taken off apart and it was full of grime and such. It had a really weak looking seal and I think the vents were hooked up wrong. As I understand one of them goes to vacuum on the manifold and one goes to intake elbow between air filter and maf sensor, correct? I don't want the same thing happening again.

Thread Tools
Search this Thread

All times are GMT -5. The time now is 12:41 PM.