308QV not starting Part 3

Once again our baby will not start. Starter turns, fuel pump runs, cold start injector is spraying, just no spark at the plugs. Other than the alarm, (which I have not verified is the problem) what could be causing this? Anything I have missed in my list of checked items?



BTW...finished the new brake lines today. They look sweeeeet!!!!! Too bad no one can see them.


JL

Try cleaning the engine connectors on the left side of the compartment with electrical spray cleaner. My coil voltage went from 10.5 volts at the positive terminals to 12.3 volts and now the car starts and runs. Don't ask me how long it took to diagnose this problem...Patrick

Are you referring to the two inside the left rear wheel well? I have cleaned those the last time I was having this issue.


Jeremy

Jeremy, those are the ones. Also check you terminals at the battery...Patrick

Battery terminals are clean and tight. The engine will turn fine, just no spark at the plug.


JL

I checked for power at the digiplex computers. All looks good. Both plugs light up when touched with the test light.

So to re-cap:

Starter turns
Fuel Pump is working
Cold start injector is working
Digiplex computers are getting power
Coils are getting power

No spark to the plugs


Anything I haven't checked yet?

JL

The only thing not on your list that I can see is Pick-Up Sensors signaling Digiplexs. After everuything is powered up, the Pick-Up Sensors have to send a signal to the Digiplex Units to trigger the coils to fire.

It is possible to make a PUS tester with a .3v bulb and leads hooked to the PUS plugs. As the flywheel trigger passes by the PUS it collapses the internal field producing a minute electical signal. They can also be tested with an ocilliscope by viewing their sine wave pattern.

HTH's

Regards, JRV

JR was right on the money, again! I disconnected all three flywheel sensors and cleaned the connectors up all nice and pretty like. )Not an easy task as they are buried under all the hoses on the driver's side of the engine.)Once they were cleaned, she fired right up. Thank you again JR for the expert advice and walking me through the diagnosis process. Couldn't have done it without your help. Also, thank you Patrick for your insight as well. Now I can test the new brake lines, but that will have to wait until tomorrow as I have a date with a go-kart tonight.

SWEET! Glad to hear you fixed it. I agree, other than the rear sensor, the others are a bit difficult to get to...

Thank you Dave. Looking at the TR JR has in the shop for a major makes me want to upgrade. A lot more room to work in.


JL