FordJim
New Member
Hey everyone, I'm new here. Howdy!
I have a 2008 Expedition Limited EL that I bought new. It is still in impeccable condition.
I've never had any problem smogging this car here in California. This time, I'm having problems.
When I do the drive cycle, I am able to quickly clear all the monitors. Here is the output screen from one of the OBD2 apps I use ("Car Scanner" on my iPhone with an ELM327 BlueTooth dongle) after a successful drive cycle:
Note the Cat and Evap are now "PASSED". Yay!
But then, by the time I get ready to head to the smog check shop, I double-check the monitors again with the ODB2 app, and the Catalyst and Eval have become un-ready again! Here's is the screen shot from the app:
Note the Cat and Evap are now "NOT PASSED".
I have done this 5 times now so far!
I thought maybe the battery was weak, since I've seen a weak battery cause monitors to reset on vehicles before. So yesterday I replaced the battery with a brand new fresh Interstate top-of-the-line AGM battery. The engine spins WAY faster now when I start it up, but the problem continues. Today with the new battery installed, I did a new drive cycle, the monitors all got cleared, then when I came back to the vehicle this evening to check, the Cat and Evap monitors are un-cleared. Argh!
It seems like the ECM might be browning out upon starting the car, or something is causing the ECM to clear its memory.
What should I look at next on this? Is there a battery in the ECM or a capacitor that gets old or some corrosion that happens?
Thank you in advance for any ideas of how to possibly fix this!
-- FordJim
I have a 2008 Expedition Limited EL that I bought new. It is still in impeccable condition.
I've never had any problem smogging this car here in California. This time, I'm having problems.
When I do the drive cycle, I am able to quickly clear all the monitors. Here is the output screen from one of the OBD2 apps I use ("Car Scanner" on my iPhone with an ELM327 BlueTooth dongle) after a successful drive cycle:
Note the Cat and Evap are now "PASSED". Yay!
But then, by the time I get ready to head to the smog check shop, I double-check the monitors again with the ODB2 app, and the Catalyst and Eval have become un-ready again! Here's is the screen shot from the app:
Note the Cat and Evap are now "NOT PASSED".
I have done this 5 times now so far!
I thought maybe the battery was weak, since I've seen a weak battery cause monitors to reset on vehicles before. So yesterday I replaced the battery with a brand new fresh Interstate top-of-the-line AGM battery. The engine spins WAY faster now when I start it up, but the problem continues. Today with the new battery installed, I did a new drive cycle, the monitors all got cleared, then when I came back to the vehicle this evening to check, the Cat and Evap monitors are un-cleared. Argh!
It seems like the ECM might be browning out upon starting the car, or something is causing the ECM to clear its memory.
What should I look at next on this? Is there a battery in the ECM or a capacitor that gets old or some corrosion that happens?
Thank you in advance for any ideas of how to possibly fix this!
-- FordJim
