That makes things much easier, a simple diff amp will do the job. This shows the general idea, but is not a complete design.
Getting the gain and offset reasonably accurate will need low tolerance resistors, but I don't know how much error is acceptable. Deriving the offset from the 5v rail should be ok as this is a reference supply for the sensors on an engine management system, so should be well regulated.
Wow! Thank you very much.

I would not have been able to come up with something like this on my own!
I'm no good with LTSpice, so I recreated it in the Falstad simulator, and it works great! To test it, I made the addition of a voltage-controlled-voltage-source node to simulate the voltage output of the GM sensor by taking the node's voltage input as pressure instead of volts, and setting the output to be the transfer function of the sensor.
A few questions about this circuit:
- I see that the parallel 470k/130k pairs give a combined resistance of 101.8k. I suppose one could use instead a series pair of 100k and 1K, but was the parallel arrangement made to get exactly 101.8k, or is it something to do with tolerance error? Because, as I make it, if one were to use 1% grade resistors, the series pair has lower overall tolerance error than the parallel pair - assuming you don't need exactly 101.8K.
- I looked up the LT1782, and it is described as an 'over-the-top' op-amp, where inputs can exceed the supply. I presume this has no bearing on the circuit, seeing as both inputs are ultimately derived from the same 5V reference supply as the op-amp has, so can never exceed it. Is this the case, and almost any rail-to-rail-input-output op-amp could be used? For example, MCP6001.
- Extra protection of the op-amp inputs is not needed, right? Because the high resistance values used will limit current greatly? So, if for example the sensor input was accidentally shorted to +12V, the protection diodes of the op-amp should be able to handle it?
Finally, could you explain a bit about how it works? Also how you derived the appropriate resistance values?