Hi all,
I am finishing up my 5.3 swap in my 88 camaro. I am not getting anything from my factory gauges for the most part. 5.3 is controlled by Holley terminator x.
Factory wiring to dash.
Speedometer - reads about 6 mph slow. Have a 700r4 trans in the car.
Fuel - I have plastic ls tank with racetronix hotwire kit. I did the 0-90 ohm swap but tank shows full all the time. Car runs so I have gray connected to green on holley, blk is gnd, and pink is to gauge right?
Coolant temp - I have green wire connected to sender on rear pass side of motor. It either shows min or max - no in between
Battery - only one that seems to work ok
Tach- stuck at around 5500
Oil pressure - Don't have anything connected for it.

Gauge fuse is good, dash lights up as normal, I can't seem to figure this out. If anyone can offer pointers I'd appreciate it. Especially with fuel gauge. Just got it running and don't really want to end up in middle of road with no gas. Btw, I did search but couldn't find much that applied or what looked like it may had bad links etc. Thanks in advance!

 

As far as the fuel sender is concerned, there are (2) purple wires from the LS tank, these are the fuel level sender wires that connect to the gauge, polarity does not matter, it’s a simple resistance coil. The pink wire that you mentioned is most likely a 12v source and is what is likely causing the gauge to peg full. As for the other wires associated with the Holley ECU to your gauges, I am not familiar with that, but there are many people on here that can help you with that.

 

I see...I have both purples tied together and connected to the factory pink going to gauge iirc. I will further investigate and run another wire if I need to or separate them and connect one at a time to see what happens. Thank you!

 

Yes, the 18AWG Pink Wire that Goes from the C313 Fuel-Tank Pass-Through Connector to the Fuel Level Gauge...
needs a 0-90 Ohm Sending Unit/ Level Sensor, for the Gauge to operate properly.

 

I thought one of the wires from the 4th gen sender has to be grounded.

 

Just to be clear - I have eliminated the factory ECU. Does that affect the operation of the gauges or are they independent of the ECU. Voltmeter works, but others do not.

 

I'm pretty sure almost all the gauges are independent of the ecu. I was able to make my gas gauge work by connecting the sending unit to the car with the key on and no ecu, just power to the fuse box.

I think only the speedometer goes through the c207.

Sounds like you're doing what I was thinking of , using the second head for a coolant temp sensor so the Holley can use the one it wants. I guess it don't see why that wouldn't work other than I don't think the factory temp gauge is really accurate.

 

Ok I got the fuel gauge working yesterday. So today I am going to work on temp gauge. It will sometimes be at minimum and as soon as car is started and is the least bit warm it will max out. I have an extra sender that I will install today. I can't think of anything else it could be since its just the single green wire, but I'll confirm that. Then I'll move to tach which is a single white wire if I recall.

Power to the back side of cluster is verified, so I believe they are independent of the ECU.

 

Which coolant temp sensor are you using for gauges?

 

This is the new one i will put in.

 

The new replacement sender does the same as the original one. Once temp reaches 195-200 it goes from bottom to pegged and no in between. I'm going to order a new ac delco unit for the old 305 and see if that works. Maybe the are chinese junk.

 

Are you sure the sender isn't for a fan switch or warning light. No power til it hits temp then full power. Instead of a range

 

I belive people were using the 98 ls1 temp sending unit should be a thread

 

I believe you are correct - the sender I have is a switch to trigger fan relays. I plan to get the 3 wire sender from the 98 ls1 as you described. Thanks for your input. Learning my way through his stuff. Now to figure out the tach.....