10-10-2013, 10:18 AM
Join Date: Sep 2010
Total Cats: -2
No fuel/No spark... ideas?
I am having a no fuel, no spark issue.
I have a 1992 1.6L turbo miata running on a Link ECU. It has been running without issues for over a year. While coming back from a trip, the car suddenly started running rough, the tach was jumping all over the place. I pulled over and it would start, run rough, then turn off. I had it towed home. The next day it started and ran with no issues for a 10 mile drive. I made a stop on the way home and it happened again - I would start it up, it would run rough and turn off while the tach would jump erratically. The next morning, I brought help to diagnose the problem - but it ran fine and I drove it home.
Now it cranks and doesn't start. I have no fuel, no spark. It turns over, I can see the cams turning (my valve cover is cut to allow access the cams) but the tach does not move.
There is no CEL and there are no codes when I jumper the diagnostic box
The fuel pump sounds like it is turning on. No fuel on the plugs when checking for spark.
I have replaced the CAS sensor with a used one with no change.
I have tried replacing the igniter with no change.
I have tried plugging in a stock ECU with no change. ECU is getting power.
I have tried replacing the main relay with no change.
I have cleaned the ignition.
I have tested the coilpacks and they seem to check out based on the values listed on miata.net
what else effects both fuel and spark? Anything else I should try/check out before diving into the harness?