P2196 on 2006 Ford Explorer V6

[jllorenz]

I have a 2006 Ford Explorer XLT 4.0L V6 - with around 170,000 miles on it. It had been leaking oil from old valve cover gaskets, so I replaced them this past Sunday. After getting everything off, cleaned, and new parts back on, I started running into new issues. First, one of the fuel injector o-rings had become damaged. When I started the car, it spewed gas everywhere inside. This was quickly replaced and put back on.

We ran the car again, and it started having more issues: trouble starting with a clank sound, thick white smoke from the exhaust pipe, rough idling, misfiring and extremely sluggish acceleration, strong gas smell, poor fuel economy and a new check engine code: P2196 (02 sensor says it's running rich).

We tried to check if there were any vacuum leaks with spraying carb cleaner around the hoses, and didn't notice any changes in the idle. The car isn't throwing any other error codes either. I'm inclined to believe a sensor didn't just randomly fail at the same time we replaced the valve cover gaskets, and that it's something we touched or did. Right now, I'm leaning at one of the fuel injectors was damaged in some sort of way, but just curious to see if there's anything else I should be looking.

 

[js11801]

I have a 2006 Ford Explorer XLT 4.0L V6 - with around 170,000 miles on it. It had been leaking oil from old valve cover gaskets, so I replaced them this past Sunday. After getting everything off, cleaned, and new parts back on, I started running into new issues. First, one of the fuel injector o-rings had become damaged. When I started the car, it spewed gas everywhere inside. This was quickly replaced and put back on.

We ran the car again, and it started having more issues: trouble starting with a clank sound, thick white smoke from the exhaust pipe, rough idling, misfiring and extremely sluggish acceleration, strong gas smell, poor fuel economy and a new check engine code: P2196 (02 sensor says it's running rich).

We tried to check if there were any vacuum leaks with spraying carb cleaner around the hoses, and didn't notice any changes in the idle. The car isn't throwing any other error codes either. I'm inclined to believe a sensor didn't just randomly fail at the same time we replaced the valve cover gaskets, and that it's something we touched or did. Right now, I'm leaning at one of the fuel injectors was damaged in some sort of way, but just curious to see if there's anything else I should be looking.

Did you ever find the solution?

After a disassembly for timing chain replacement, I have the same issue - p2196 and "thick white smoke from the exhaust pipe, rough idling" and "strong gas smell,"

I can not find any vacuum leaks, I changed the passenger side Fuel injectors, plugs, and all new spark plug wires.
The plugs were very blackened.
When changing the fuel injectors, I inspected the new intake manifold gaskets and they looked ok. Timing between camshafts was also rechecked.

I'm going to change out a few vacuum hoses, but if that does not fix it, I'm headed to the mechanics, unless someone else has something else I can check.

 

[js11801]

Did you ever find the solution?

After a disassembly for timing chain replacement, I have the same issue - p2196 and "thick white smoke from the exhaust pipe, rough idling" and "strong gas smell,"

I can not find any vacuum leaks, I changed the passenger side Fuel injectors, plugs, and all new spark plug wires.
The plugs were very blackened.
When changing the fuel injectors, I inspected the new intake manifold gaskets and they looked ok. Timing between camshafts was also rechecked.

I'm going to change out a few vacuum hoses, but if that does not fix it, I'm headed to the mechanics, unless someone else has something else I can check.

Took it to a mechanic and they said it's either the PCM or the wire harness. I'll bet on the harness as it got moved a lot during the timing chain work.

 

[js11801]

Took it to a mechanic and they said it's either the PCM or the wire harness. I'll bet on the harness as it got moved a lot during the timing chain work.

Fuel injectors. Removing the rail to remove the valve cover gasket damaged the injectors - probably dirt.
The replacement non-Motocraft injectors were much too rich and the computer could not trim it lean enough.
I bought Motocraft injectors (yes, expensive) and that resolved the issue.

The monitoring tool showed short term and long term fuel trim as low - that was the computer trying to send less gas into the cylinder, but the injectors. Trust the diagnostics!