Is my engine cooked?

Hello all,

I have a question, I’ve been chasing a stumble at idle, usually my engine starts smooth and when driving has no problems, but when at idle and warm I have a stumble that’s intermittent. i’m averaging -7 to -11% fuel trims (new injectors brought it about 6% closer to 0) and have a gas smell in the oil, but no noticeable change in oil level. I have changed plugs, wires, coil pack, vacuum test, injectors, cleaned and tested idle air control/throttle body, and am feeling like the dreaded compression test is next. (No CEL) Any tips?

 

I had this on my 2.7 then it got rear ended and totaled before I starting to chase the problem. I was going to do everything you did starting with spark plugs. This problem did develop after I had a cracked radiator and my truck overheated. Not sure if that was the cause or coincidence. Did your truck ever overheat that you know of? Do you notice any drop in coolant level? This could be signs of a head gasket. Maybe a timing issue? I'm not super knowledgeable, but just throwing some ideas in the pond.

Edit: It could be fuel starvation as well? clogged fuel filter or anything in between.

 

I don’t know if it has ever been overheated unfortunately, but I did block test and it came back fine, no blown head gasket. Coolant level has been very consistent, it does need to be flushed but pushing that until i solve this issue.

 

could just do an OBD2 scan to see if any codes are stored without CEL, you did a vacuum test so im assuming theres no cracked vacuum hoses and a cracked air intake hose would probably throw up a CEL. I think i'm out of ideas after that.

 

Already scanned for codes, nothing stored. Had an EGR code, changed the modulator and it went away a while back. I appreciate your input, and sorry about what happened to your 2.7

 

As you mentioned I would do a compression test and cylinder leak down test. Hopefully fingers crossed its not a bad headgasket. good luck

 

Have the valve clearances ever been checked? That usually needs to be checked every 50k or so on these engines as they have a habit of tightening up.

 

Not yet,

I am amateur level so don’t trust myself to do that in all honesty. I’ll do a dry/wet compression test, and if it makes sense, i’ll send it off to get that done