Raispis99

This is my first thread so hopefully it’s in the right place.

i have a 1996 LS400 that had a really bad misfire for a while. Changed out my spark plugs and the car ran great for 15 miles. Then the misfire came back hard. Just swapped out the plug wires (I think that’s what there called) and it ran like new for another 15 miles, now it’s got a small misfire and is burning oil. I’m stumped but I think it’s distributors.

i just don’t know why it would drive like it’s repaired then go back to misfiring. Any tips or knowledge would help a lot.

Yamae

There must be a reason why only 15 miles. The ECU is acting up somehow strange. In order to replace parts you had to stop the engine. Stopping and starting again means there were two resets of the ECU going on. When you stop the engine, the power off reset is done and when you start it again, the power on reset is done. Your ECU is not functioning well and it requires to be reset after 15 miles of run. Probably the ECU's Vcc 5V line is messed up with too much ripples. I'd check it and confirm by this method.