joejoe

'84 n/a will crank but not start. This happened all at once. I did change the radio before this, but no wiring was disturbed other than that for radio. (is there anything in center consol on bottom that may cause no start?) When cranking the tach does not move at all. I jumped dme relay and fuel pump runs.

I have read that this may be reference sensor gone bad (possible?) If so is there a way to test? Are these difficult to replace correctly in the car? (reference sensors and new relay are on the way) I also tried swapping dme relay with 2 others but still only crank and no start. Battery is fully charged (and sitting with maintainer right now)

Lastly is there a possibility that alarm has engaged? It does not sound when door, hood, or rear hatch opened, but I just don't know if it is something to consider. If it may be is there a way to bypass? Any and all suggestions are appreciated, Don.

Black51

Yes, without further testing, it's probably the reference sensor, seems to be a common thing going bad these days. Try wiggling the s@#$ out of it to see if that makes the tach bounce happen. That's the exact problem my car got as well. You should be able to see some level of fraying or splitting in the cable insulation, which is a tell-tale sign of sensor failure.

I think some people have had luck with the alarm thing, but more often than not, it's the ref sensor. Check that first.