Jay351
Member
Thread bump!
Been a few years since I’ve really gotten back into this issue with the truck. I ended up restoring the rest of the truck and am now just sorting out engine details.
I recently purchased a used Snap on mt2500 scanner. After wiring up the semi circle diagnostic plug, I’m finally able to see What’s going on.
I noticed that after the engine started to warm up, the ecu would go into closed loop and would begin detecting knock at idle. At 10 degrees, 900rpm, idle switch closed it was detecting knock. Up to around 2500 it would see knock off and on but after then it would be fine. Timing would pull down to 40-50 degrees at that point.
Engine sounds fine, no questionable rattles. Great oil pressure 90psi cold, around 20psi hot at idle. Engine has all new oem ignition components including coils. Replaced capacitors in the ecu (also tried a spare ecu) New denso primary o2 sensors. New injector seals. New 3vze replacement denso fuel pump, new oem fuel filter (new lines as well due to rust).
I recently had an issue with a bad starter trigger wire under the manifold. So I ended up sourcing new connectors for the engine, bought some shielded wire and made my own harness. I left the original knock sensors in place. Wondering if these sensors can become more sensitive as they break down?
I’m going to get the truck licensed so I can run it down the road with the scanner to see what it does under load. Just been playing with the “new” scanner in the shop.
Been a few years since I’ve really gotten back into this issue with the truck. I ended up restoring the rest of the truck and am now just sorting out engine details.
I recently purchased a used Snap on mt2500 scanner. After wiring up the semi circle diagnostic plug, I’m finally able to see What’s going on.
I noticed that after the engine started to warm up, the ecu would go into closed loop and would begin detecting knock at idle. At 10 degrees, 900rpm, idle switch closed it was detecting knock. Up to around 2500 it would see knock off and on but after then it would be fine. Timing would pull down to 40-50 degrees at that point.
Engine sounds fine, no questionable rattles. Great oil pressure 90psi cold, around 20psi hot at idle. Engine has all new oem ignition components including coils. Replaced capacitors in the ecu (also tried a spare ecu) New denso primary o2 sensors. New injector seals. New 3vze replacement denso fuel pump, new oem fuel filter (new lines as well due to rust).
I recently had an issue with a bad starter trigger wire under the manifold. So I ended up sourcing new connectors for the engine, bought some shielded wire and made my own harness. I left the original knock sensors in place. Wondering if these sensors can become more sensitive as they break down?
I’m going to get the truck licensed so I can run it down the road with the scanner to see what it does under load. Just been playing with the “new” scanner in the shop.