You basically need these 3 to get the engine to fire up. Of course there's more, but this is where you start. If you know you have spark, you can rule that out. ("Weak" spark is SO rare of a problem, let's not complicate this.) Have you checked if you have fuel? Do you even hear the fuel pump "prime" for a couple of seconds when you turn the key to the run position (not to the start position, just Run). If you don't hear the fuel pump prime for a couple of seconds, the fuel pump is not running. The last thing is spark or fuel timing. (Crankshaft position sensor or camshaft position sensor. I don't know which the RR uses to control spark and fuel timing, but that's where to look. Don't assume the fuel pump or any sensors have suddenly failed. This is too coincidental. Always look at the last action you performed. You removed the head(s). In that process, there are a multitude of connectors you had to disconnect. Check them all.

One more thing that might be helpful is to use a scanner to pull any codes. There's little chance one has been stored because you can't even get it to start, but there are a number of codes that do get reported without starting.

 

The fuel pump doesn't turn on when the ignition is on. However, I jumped the relay, and can hear the pump running, but still can't get it to start. There aren't any fault codes being displayed on the ignition diagnostic display; I swapped out the display with another one, and still nothing. My understanding is that once you disconnect the display, you should get error "02" after reconnecting it. But I don't with either unit; it's just blank. I have, of course, checked all of the connections multiple times. Does anyone have an explanation for the relay clicking that I described earlier? I know the fuel pump is running, but the spark plugs are dry, so clearly the injectors aren't working. Would the next step be to swap in a new ignition control module?

 

did you try the ether test?? a 2 second spray will tell you a lot