misfire 2 cyl 4.0L OHV - shop wants to...

[dakotablu]

I just received a call from my mechanic saying he needs to remove the right head because a leak down test showed problems on cyl 2. I took it in last Thursday after finally getting a P0302 code. He contacted me on Friday saying that compression check was good, plugs good, wires good and coil good. He wanted permission to remove the upper intake manifold to swap injectors to see if that was the problem. That still didn't correct the misfire. He's estimating $1300.00 to pull the head and possibly find a burnt or carboned up exhaust valve. I'm guessing that includes rebuilding the head. What does anyone think? I added a can of seafoam to the gas and drove it about 100 miles before I took it in. Co-worker recommended Trying regular injector cleaner for a couple of tanks to see what happens. Unit only has 69000 miles. 2000 Ford Ranger XLT. Thanks in advance for your thoughts.

 

[radman]

What happened after Friday?

If your repair shop said the compression checked good on Friday why do you suspect burnt or carboned up valves now? Sounds like you might want a second opinion before going much further.

 

[boominXplorer]

I am going to say cracked head or head gasket. Sometimes neither will lower compression numbers enough to show something is wrong.

I just had a 99 in my shop for the same reason. Customer gave up and brought it in after a new plug, wires and injector. I pulled the plug, pressurized the cooling system and after a minute or so drip drip drip out the spark plug hole.

 

[dakotablu]

I appreciate your responses. I've already called the shop and told them to button things up - I'm going to look for a second opinion. Just seems strange to me that it only misfires at idle. If it's a cracked head or head gasket wouldn't I still show misfires on the OBD2 scanner as I'm going down the road?