check engine light

[dwelytok]

i took my 96 sho to the mechanic today for the check engine light being on and the battery light comein on also he told me that the #4 cylinder was misfireing so he swaped the coils around and is still comeing up with the same code dose anyone have any ideas on what it might be and as far as the battery light on he tryed to tell me that it was still charging at 14 volts what might couse that thx

 

[Porkchop]

Alternators can still be bad and charge at 14v. If the battery light is on, get it replaced the light is there for a reason.

As for the misfire, if it is throwing a code the coil is already gone. Swapping it around will do nothing but move the misfire to another cylinder. NE SHO has new and used coils for a very affordable price. Check them out!

 

[ArkanSHO]

Couple of questions first: Did he clear the code for the # 4 before he restarted it and what is the voltage from the bettery when it is off?
The reasons I ask these questions are that it certainly is possible for other issues besides a coil to cause a missfire. A plug , injector or even a bad piston ring can cause the code. The code is tripped when teh engine detects a loss of RPM when it should be firing that cylinder. On the front of the crankshaft is a sensor that detects the RPM very accurately.
The battery question is because the alternators are routinely suspect on these especially as of late on teh V8 SHO list, but a bad battery will cause the alternator to overload shortening it's life, I have personal experience on that. Another issue could be the MEGA fuse or alternator fuse in the underhood fuse box is blown and even though you have power from the alternator it isn't charging anything. I have also experienced this and a cross threaded Mega-fuse post nut that was crossthreaded that ruined a battery and alternator simultaneously.

 

[1993MTXSHO]

dunno how the gen III's are but on my 95 gl i used to have before my SHO, the alternator light used to come on sometimes. All it was was the plug on the alternator was falling out so the computer was reading nothing. Just check your electrical connections, Im assuming you did this already or your mechanci did but just fyi.

 

[dwelytok]

he did clear the codes and then it still came up with the code for #4 we just put 8 new plugs in it and As far as the charging goes it is a brand new battery

 

[ArkanSHO]

he did clear the codes and then it still came up with the code for #4 we just put 8 new plugs in it and As far as the charging goes it is a brand new battery

Well then, that is not looking so good then, sorry. Pray for a bad coil feed wire cause the other options are real expensive, not that a harness isn't if you go that route, but splicing a couple feet of wire would cetainly be cheaper then the piston , valves or rings having and issue. Of course it could still be the result of a head gasket, but it would be a rare occasion to be sure.

 

[dwelytok]

we just put new injectors in it now we are going to put a differant coil in it and hope that it is the coil we are getting good power to the coil so dont think is a bad coil feed wireand just to make sure the #4 is the one on the back all the way on the drivers side thx

 

[ArkanSHO]

Interesting article since the resolution would have taken less time not to mention cost then just changing the coil or connecting the FORD STAR system to it:
Coil failure diagnostic article

 

[dwelytok]

Interesting article since the resolution would have taken less time not to mention cost then just changing the coil or connecting the FORD STAR system to it:
Coil failure diagnostic article

i thank u for that i will just change the coil and see if that fixes the prob if not it is going to the ford dealer

 

[ArkanSHO]

By the way, the Murray Auto coils are only around $59, most of the others are $75 and up. The Ford OEM is well into the $130 - $149 range as I recall, probably more now.