so i am putting in a 3800 and still amassing parts and i thought how easy it would be to put a fire bird gauge cluster in a fiero if the cluster is set up to run those gauges already any one else under that impression. repin my wires and plug it into the cluster and whalah it works ???? am i just thinking it will be too easy?

I'd do the engine swap first and then the dash swap later. There is no advantage in doing both at the same time, however there is a disadvantage. If you do both at the same time and something doesn't work you won't know if it is the engine swap or the dash swap.

got it. on the swap the engine will be running correctly before anything happens i am just looking foward. like does the computer need special programming for the firebird gauges?

The fuel tank sender sends the signal that the gas gauge. The oil pressure gauge sender sends the signal that runs the oil pressure gauge. On the 3800 the part known as the 3 wire coolant temperature sensor is actually a combo unit consisting of a 2 wire CTS (that runs to the computer) and a separate temperature gauge sender, which is wired to the temperature gauge. So none of these senders(sender half of the combo unit) has connection to the computer.

The 3800 computer controls the alternator. The computer thus has a wire that runs to the 'charge' light. This is a simple on/off light.

The voltage portion of the "alternator" gauge just runs off of the cabin voltage.

The 3800 computer also has an output to run the TEMP light. This also is a simple on/off light. The PCM is programmed for the temp that light comes on at.

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There is no programming the ECM/PCM has that runs either the stock or Firebird gauges. They simply just run by being electrically connected to their senders.

[This message has been edited by phonedawgz (edited 11-23-2013).]

Sounds similar to the 3900 LZ9 harness I'm doing. Be sure to use the V-6 harness as it is easier than trying to adapt to L-4.
You may want to check with JScott seeing how he does a lot of the FB dashes.

Not sure on the fire bird gauges but one problem using newer gauges is the feeds to the gauges them selves are often data line fed instead of individually fed and some cars the fuel sender feeds the PCM then the PCM works the fuel gauge. Again not sure how the fire bird does this but some thing to watch for. Dan

i was planning on cutting my fiero connectors that go into the harness and take come c203 connectors and make a harness connection from 2 of those because they are easy for me to get and easy to plug and unplug than the connectors that plug into the gauges.

No need to reinvent the wheel when a plug and play harness for the Firebird gauges has already been developed...