When they found the low compression in #8, did they squirt some oil in the cylinder to rule out bad rings?

 

Delphi FJ10566 Fuel Injector : Amazon.com : Automotive

 

I have to pickup the truck in a few, but I believe they did a wet compression test and ruled that it would be either a bad valve or an injector that causes the misfire. They cut me a deal on the labor, but in case it is the injector, it would still be too much.

I am going in the engine today and start taking a look at the injectors to see if there is a leak, or if I have to dig further.....

If it is an exhaust valve, it is not a bad as it would be a piston or such.

 

Basically I feel i simply lost $400. I gave the shop permission to go in the block to pinpoint the problem. After a day they came back saying it was a burned exhaust valve, and to complete the job the cost would be $1,800.

After i was done laughing, I asked them to get it ready to be picked up. We brought it home to see what they actually did, and they actually did not even take the cylinder head off.

My question; can they see somehow already through diagnostics that the valve is bad, or is a wild guess on their part as they said that the injectors were ok because there is fuel flowing through injector 8.

I feel they guessed it is a valve, hang a nice price on it and then fix whatever the problem is, or they found it already but still try to ask for a huge amount of money.

Ps, this is a service place that has many places around.

 

If they torn into the engine far enough to physically see the burnt valve they would have had to remove the head. Which means you would have paid for a head gasket, head bolts, intake gasket, valve cover gasket, coolant , oil etc... Would be impossible to do it in a shop for $400. Labor calls for 8 hours to remove 1 head. At my work that would be $736 in just labor. There is a small chance they removed the exhaust manifold and could see it from there however the labor to R&R the exhaust manifold is 1.5 hours $135 and maybe $50 in parts. Also I would not consider removing the exhaust manifold as "going into the block". So what did they do for $400? There are many ways the prove a bad valve without "going into the block".

As long as they did the compression test correctly it does sound like you do have an internal engine problem. A bad fuel injector will not cause low compression especially if oil was added to the cylinder when doing the test. You need have someone perform a cylinder leak down test.

 

When I brought it in, all i wanted was diagnostics in the hope they would find the exact problem of the misfire 308, knowing it was a cylinder. That was $110.

When I picked it up, they told me that there were three engine codes, which i knew already, nothing new, and they mentioned to be see what exactly the problem was, they needed a tear-down of the engine, costing $700. I declined and then they dropped it to $400. I agreed as they would ignore the diagnostic cost.

When I got it back today, I noticed that they did not take the head off or the exhaust, or the intake manifold.

So basically when they told me the cost of $1,800 to replace the valve, and check the other side as well, I wondered if they just guessed it as all they took off was the valve cover, the belts, the fan, and some related components.

To me that is not a tear-down, but rather a "let's pull some parts quickly and see if they bite" method.

Now I have no choice than to take the head off as that is my only go-to point with this misfire. It makes sense that there is a burned valve as the car keeps running rich, and I noticed that when engine is cold, all is good, but when engine gets warm, engine light comes on stating the engine is too rich.

 

So I started working today on the 350, and found so far that the intake is fairly wet due to fuel. i am not sure yet if this is an actual problem, but maybe one of the experts here in the forum can tell me.

I have a picture attached from the wet intake area.

Thanks!

 

Many of the issues explained can be caused by the failure of a simple coolant temperature sensor. The (master sensor ) or coolant temperature sensor controls almost everything from fuel enrichment to ignition causing hard starts rough idle rich or lean conditions and even random misfires so I would change this 20 dollar part before I ever investigated further and spent countless amounts of money on unneeded repairs