Kenneth 1948

We have a 1986 Nissan Sentra (New to the board, hope I'm posting in the right place)

Most of the time it runs fine but occasionally after a 1 hour run up the interstate it will slow down and die and not re-start until it cools down although it does not run abnormally hot.

This past weekend I did some trouble shooting, late on a wet night on I-40, not a fun experience.

Cranked fine, plenty of fuel, no spark from the coil.

Checked all visible connections, tried hot wiring from the battery to + on the coil, no spark.
Then after about 1/2 an hour, started and ran strong for a few miles then had to stop and died again when I went to speed up the engine from idle.

Left it overnight beside the highway, next morning it started, ran OK at highway speeds and idled through a traffic jam! still running fine although does not usually give us problems around town.

I am not familiar with these engines. Is there an ignition module that could be failing intermittently?
When it runs it runs OK, doesn't miss. When it dies it stops dead, doesn't miss or back-fire.

That's about all the symptoms I can describe. Sure would like to have some ideas before I start throwing parts at it.

Thanks,

John aka Kenneth

Fins510

You might want to get Haynes manual and test the ignition module in the distributor as well as the iginition coil itself using VOM (volt-ohm meter). Check for oil under the Dist. cap, if there's oil it could be causing the module to fail to ignite the coil. Also, when the car is dead, check for spark at the coil when cranking the engine. Then you'll know for sure it's something related to the ignition circuit (coil, electronic ignition module, etc.)

Kenneth 1948

Thanks so much for the response.

When the problem occurs there is no spark at the coil so we know for sure it's ignition.
There is no oil visible under the cap.

I think we're on the right track but according to the parts catalogs and the local Nissan parts counter guy, this car does not have an ignition module in the distributor. That is only in California and I'm in NC.

Yes, could be coil and there's a "Power Transistor" I believe this is the shiney thing mounted next to the coil which is prone to intermittent failure but it's not cheap.

Thought about replacing coil and transistor with components from junkyard but the risk of course is that they too could be bad.

Please let me know your thoughts. Thanks, John aka Kenneth