Hi all, been trying to fix this problem with my lady's truck, but having troubles.
She's got an 01 Tacoma, 2.4 litre engine, with about 146k miles, but it was rebuilt a while ago. She complained to me that it was running really bad, and that the engine was shaking and it was having trouble off the line, with the CEL on, and sometimes flashing on/off. So naturally, I take it for a drive and can't duplicate the problem, and it seemed like the problem went away. It did it again a day later, so I told her to take it to a local shop to have the OBD codes pulled off so could figure out what to do with it. They told us the codes were:
P0304 - Cylinder 4 Misfire
P0110 - IAT Sensor Circut
P1300 - Igniter Circuit Malfunction - No. 1.
To duplicate the problem, I have to drive it for a little bit, park and then get back in the car after about ten minutes. Like, going to the grocery store for just a few items. The shop we took it to recommended a new IAT sensor, new coils for cylinders 1 and 4, and a new fuel filter. Then, out of nowhere, the problem went away and was fine for almost eight months. We drove to Mammoth lakes, Los Angeles, everywhere. It was for all intents and purposes, problem free again.
Then the problem resurfaced out of nowhere. So I got the write up out and bought the parts they recommended. I replaced the MAF and the coils, but the problem persists. Sometimes it starts fine, and sometimes it starts rough. I put in new spark plugs, and the air cleaner was changed recently as well.
Anyone got some diagnostic tips for me to try to pin down the problem? I got a multimeter, so I can check the electronics, but I don't know electronics very well, so I don't know what to check and what my measurements will tell me.
Thanks a lot, folks.