Misfiring and codes after driving with exhaust leak. Hidden issue?

[littlejth]

Hi all,



I've been driving my epxplorer for a total of about 6 months with a (now) major exhaust leak in the passenger and am getting ready to fix it, however I have a question about whether or not I may have other issues to worry about as well. Recently, I've noticed that after the truck has been warmed up and/or driven for a few miles, then stopped and started again (i.e. making a quick stop at a gas station or something) the truck idles lowly and begins chugging a bit. I hooked up my bluetooth OBDII adapter to Torque on my phone and found out that the truck was misfiring; the total misfire count on Torque was usually between 5-15 after letting it run for about 30 seconds. This only happens when the truck is started after already being warmed up and does not continue in regular driving or after parking the truck and letting it idle. The truck has thrown P0171, P0174, and P0455. Could there potentially be another issue here or can this be attributed to the to-be-fixed exhaust leak? Thanks in advance for any help.

 

[gatzdon]

If that exhaust leak is your EGR tube, then yes it could cause any number of errors.

Strangely enough, when I replaced mine, it was less than $50 through Fordparts.com at a local dealer, despite everyone online wanted $100+. You have to buy the adapter (to the exhaust manifold) as it's usually fused to the EGR tube. EGR valve may get damaged removing the connector at the other end.

A large evap system leak would also cause those codes as unmetered air is being introduced the engine.

 

[JusTheUsual]

It seems like you should run a fuel pressure test 1st. Also have you been loosing any coolant for that can pertain to head gaskets because that can cause whats happening with the start up rough idle clearing the antifreeze in cylinders. Happened to mine

 

[gatzdon]

It seems like you should run a fuel pressure test 1st. Also have you been loosing any coolant for that can pertain to head gaskets because that can cause whats happening with the start up rough idle clearing the antifreeze in cylinders. Happened to mine

It doesn't take much coolant in the cylinder to cause startup misfires.