Nissan Repair: 1987 Nissan truck sudden problem, nissan truck, nissan dealer

Question
Only 60,000 miles, sudden problem developed after driving 120 miles to visit family. Regular repair shop could find nothing wrong.  Nissan dealer had for 10 days, $400 in parts and 11 hours work and they found nothing wrong (no charge!)  Ran perfectly on day one of trip.  Filled up with gas, drove another 50 miles.  Next morning, started up but very rough, bucked unless going down hill.  Got much worse on 15  mile trip.  Next morning, on return home, could barely make it up hills, and soon no relief heading downhill.  Four hours to go 120 miles, bucking all the way, died at every stop light, could not go over 40 mph. Any hope?  Thanks.


Answer
Hi Janet -

If I could see or know what the repair shop replaced, it would help me a great deal. My fax number is (808)732-0561 if you want to fax the receipt, or just let me know what was done. However, just at the top of my head, I would check the following in the order of possibility:

Check for electrical corrosion at the following areas:
Spark plug wires at spark plugs (physically remove and check)
Spark plug wires at distributor terminals (physically remove and check)
Distributor cap (check inside cap for carbon tracking)
Distributor rotor (carbon tracking)
Ignition coil (the coil itself rarely goes out, however check the tower where the wire plugs in)
Possibility it could be the wires themselves or spark plugs, if that was not changed yet.

You also may want to check for fuel pump output. Obviously, under load the engine misses, so I think it is electrical. You are looking for anything (corrosion, carbon deposits, bad connections, etc) that could cause one or more plugs to misfire. This could be anywhere between the ignition coil and spark plugs. A thorough inspection is needed, and I hope this guide helps you.

I can probably give you a better picture if I know what was done so far to the vehicle.

Hope this helps, and get back to me -
aloha
calvin