2008 Mountaineer Issue

[leftoverture]

Hello. I am trying to help an elderly friend. He has a 2008 Mountaineer with the 4.0 engine. He tells me the engine overheated and ever since, when the engine gets warm it develops a miss at idle. I looked over the vehicle this weekend and pulled codes. The only code is P0302. When cold, it idled fine and actually sounded very strong. I did not hear any unusual sounds of any kind even when it got up to temp. The oil was clean and did not appear to have any coolant contamination. I let it idle long enough to get up to normal operating temp and it idled fine, but after I gave it some gas and let it return to idle, it did stumble and seemed to miss. I gave it gas again and it returned to a normal idle. This gentlemen really doesn't have the money to have a shop diagnose/repair it, so wondering if anyone has any advice on where to go from here. Thanks.

 

[J_C]

So cylinder 2 misfire. You can check for moisture in the oil, exhaust gas in the coolant, white smoke out the exhaust pipe (coolant loss). You can pressure test the cooling system, and do a compression test on cyl #2.

I'd wonder about the head gasket or warped head, that it may need the head pulled and check for flatness and put new head gasket on if that's all it needs. I'd also wonder why it overheated. Was it already low on coolant?

IF it is the head gasket or you tear it down that far to check/replace, then this is probably a repair you want a shop to do, but you could seek a Chiltons or Haynes manual, see if there's any youtube videos about it. IF it's the head gasket or warped head, it's going to be expensive, several hours labor.

I don't know the clearance on an '08 but in prior generations using the 4.0L SOHC, the engine had to be pulled to get access to a bolt to do the passenger side (where cyl #2 is) head gasket. It may need a special timing tool to set timing as well. It might be cheaper to just swap a whole (used) engine in.

 

[leftoverture]

So cylinder 2 misfire. You can check for moisture in the oil, exhaust gas in the coolant, white smoke out the exhaust pipe (coolant loss). You can pressure test the cooling system, and do a compression test on cyl #2.

I'd wonder about the head gasket or warped head, that it may need the head pulled and check for flatness and put new head gasket on if that's all it needs. I'd also wonder why it overheated. Was it already low on coolant?

IF it is the head gasket or you tear it down that far to check/replace, then this is probably a repair you want a shop to do, but you could seek a Chiltons or Haynes manual, see if there's any youtube videos about it. IF it's the head gasket or warped head, it's going to be expensive, several hours labor.

I don't know the clearance on an '08 but in prior generations using the 4.0L SOHC, the engine had to be pulled to get access to a bolt to do the passenger side (where cyl #2 is) head gasket. It may need a special timing tool to set timing as well. It might be cheaper to just swap a whole (used) engine in.

Thank you. When he told me it overheated, the head gasket is my biggest worry. Though nothing is getting in the oil. I did not notice any large amounts of white smoke, either. But his coolant level was low and I don't know if that's because it's still leaking or because he never filled it up all the way. I used to do lots of work on cars but now I don't and I no longer have the tools needed to do all those checks. So cylinder 2 is on the passenger side? Looked like I'd have to remove a lot of stuff to even get at those plugs to check them. I am starting to think having a shop at least do the diagnostic is going to make the most sense. Then we'll have the best chance to understand the extent of the issue.