Warm start problems
When my truck was driven, and sits for about 40 minutes, it is hard to start and keep running for a couple minutes. Afr shows 20, afr trim 50%. Sounds terrible. Have to mess with the throttle to keep it running. After a couple minutes the afr goes to 13ish and it settles down. Fuel pump is running. I called Fitech. They said to check for 10.5 volts on the white wire while cranking. I couldn’t reproduce or have a helper to check it. They said the computer won’t work if it doesn’t get 10.5 volts when cranking. The sounds feasible, but how does it run at all? Why doesn’t the computer start working after it starts? Anyone else seen this problem? Suggestions?
I forgot to mention starting right after shutting off when warm is fine.
Yes, 10.5 sounds right based on what I've experienced. If it's under about 10 volts while cranking, it may start, but will run like crap and foul your plugs. I put in a voltage gauge under the dash to monitor the battery voltage while cranking to make sure it was over 10 volts before I even attempt to start the car. For some reason during the initialization of the fitech during cranking it messes it up after that if under 10 volts during cranking. Check your idle AFR setting to make sure it's not some weird number also. And take a couple of plugs out and take a look to make sure they are not already fouled, and if they are, it probably fouled out your O2 sensor also I've found. Good luck.