[jimbo]

I have been troubleshooting occasional and erratic low oil pressure and to a lesser extent low fuel pressure readings on my GRT EIS for sometime now. I finally found the problem so I wanted to share with others who might be experiencing the same issue. The fix: I moved the ground wire for the EIS FROM a stud on the engine which was shared with and on top of the ground wire for the Emag electronic ignition TO the forest of tabs ground plate that I had riveted to the firewall. This change also shortened the ground wire about 3 feet. Since this change my OP and FP have been rock solid. The manual for the EIS said to connect the EIS ground wire direct to the engine so that's what I did but little did I realize the spikes in the ground current the electronic ignition was causing.

Hope this info will save others time in their search for causes in low OP readings.

 

[Dan 57]

finally found the problem so I wanted to share with others who might be experiencing the same issue

this is the spirit
Unfortunately quite a few people come here, report some kinda problem resulting in folks scratching their heads, and no feedback...
We're all ever learning.

Many thanks @jimbo

 

[rv8ch]

After reading the Aeroelectric Connection, and following that discussion group for a couple of decades, I have become convinced that a good ground will cure many electrical issues.

 

[rsultzbach]

Aren’t you supposed to BOLT the forest of tabs grounding units and NOT rivet them since grounding quality will suffer if rivets start smoking?

 

[Mel]

Aren’t you supposed to BOLT the forest of tabs grounding units and NOT rivet them since grounding quality will suffer if rivets start smoking?

Good point. I agree!

 

[jimbo]

Aren’t you supposed to BOLT the forest of tabs grounding units and NOT rivet them since grounding quality will suffer if rivets start smoking?

I didn't use an engine side of the firewall forest of tabs ground plate. I suppose I could have added a plate and bolts just for support but I got to believe those several rivets fastening the forest of tabs ground plate to the firewall is very adequate and much lighter. On the cabin side I have bundles of ground wire zip tied together and supporting each other.

 

[gasman]

A brass or copper bolt and nut through the forest of tabs and a firewall brace with the battery ground cable attached on the firewall side. Another cable (welding cable) from the same bolt, to the engine case.

 

[rsultzbach]

I didn't use an engine side of the firewall forest of tabs ground plate. I suppose I could have added a plate and bolts just for support but I got to believe those several rivets fastening the forest of tabs ground plate to the firewall is very adequate and much lighter. On the cabin side I have bundles of ground wire zip tied together and supporting each other.

I would suggest calling B&C and asking if rivets are ok. I remember learning the forest of tabs requires a bolt not rivets. B&C will know the definitive answer.