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P0305 - Cylinder 5 Misfire

69Boss302 said:
You may not have to replace everything on this list, but it will cover everything I can think of.

from the top down:

EGR gasket
UIM/LIM gasket
Valve cover gasket to include the ring gaskets for the spark plug holes. Fel-pro sells it as a complete set.
Crankshaft bolt (Torque-to-yield)
Crank case gasket
Crank gasket
Head bolts (Also TTY)
Head gasket
Oil change
oil filter
new coolant

It will get expensive and will be difficult to do in the car but possible. The cams will have to come out to get to the head bolts. This will require you to be extremely meticulous on what goes where and everything must be kept in order. The bolts for the cams may be TTY as well, not sure.

You'll need a torque wrench, pulley puller, paper towels, degreaser (I swear by Simple Green. $9 from Home Depot for a gallon of concentrate.), beer, patience and more beer. Ok, beer isn't neccessary but helps dull the pain.

EDIT: If the car didn't overheat, chances are that the head may be ok. However, if it was a head gasket and in my car, I'd still have a machine shop look at it. They will be able to tell you if it needs to be decked or not.
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I have a feeling car is going to sit if its not a fuel problem until I can afford to put it into a shop! Takings cams out and all that stuff, well, I jsut dont think I'm going to really trust the car any if I try and do it! I'll always be wondering, what did I mess up, or what did i miss!
 
Mechanic thinks it is a broken valve spring after taking the UIM and valve cover off, but is also worried that the valve may have seated itself... (gibberish to me)

What should be my next step?
 
3L !!!

3-liter-haus-logo
 
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Trouble shooting

Trouble shooting

I was wondering how the mechanic determined that it may be a broken valve spring? Did you go through the various tests to determine what may be wrong prior to tearing into the engine? Did you compare the plugs as both Big Jim and myself suggested? The trouble shooting guidelines where developed over years to help eliminate guessing on what is wrong prior to tearing into a engine. If you did not follow proper testing guidelines then your mechanic maybe doing what we all are doing on this forum, which is guessing. Purchasing a Hayes or Chiltons manual for your car may be a very cheap investment. It is a good resource in addition to this website. Dan.
 
Dan the rug man said:
I was wondering how the mechanic determined that it may be a broken valve spring? Did you go through the various tests to determine what may be wrong prior to tearing into the engine? Did you compare the plugs as both Big Jim and myself suggested? The trouble shooting guidelines where developed over years to help eliminate guessing on what is wrong prior to tearing into a engine. If you did not follow proper testing guidelines then your mechanic maybe doing what we all are doing on this forum, which is guessing. Purchasing a Hayes or Chiltons manual for your car may be a very cheap investment. It is a good resource in addition to this website. Dan.
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Well, we did some testing, taking the plugs out, seeing the unburnt fuel on them, doing a compression check (there was none) and then tore into the engine, slowly clicked the key to start and watching the cams and valve springs and such, and thats why he thinks it may be a broken valve spring!

He said there are only a few things that would cause a cylinder to have zero compression:

anyone know what those things may be!
 
Ok, lets go back to the beginning. You said white smoke from front bank, was it coming out from the head, intake ?? Or was it from the exhaust, if from the exhaust how did you KNOW it was from the front bank?

In that post you said the head gasket was eliminated, how was it eliminated.

You asked what could cause no compression. Given the smoke I'd bet on head gasket.
 
twocontours said:
Ok, lets go back to the beginning. You said white smoke from front bank, was it coming out from the head, intake ?? Or was it from the exhaust, if from the exhaust how did you KNOW it was from the front bank?

In that post you said the head gasket was eliminated, how was it eliminated.

You asked what could cause no compression. Given the smoke I'd bet on head gasket.
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OK, when I was driving the car, it did appear as white smoke. Yesterday, I actually watched the car driveing by me, as did my mechanic, and it is actually a blueish tint smoke.

I know what bank its coming from because I have true duals, each headers has its own exhaust.

I thought/think its eliminated based on my mechanics diagnosis and because of the other signs a head gasket normally produces, such as antifreeze in the oil, and the fuel that was left on the spark plugs...
 
look back at the pictures I posted with the headgaskets. You'll see that everything is close together but just because a head gasket is blown doesn't always mean that the fluids have to mix.

It could only be blown out the middle to where the oil and coolant are still seperate. This could cause zero compression with no other effects because it is open to the atmosphere.

Could only be blown so that it opens up to a water jacket and allows coolant in. You wouldn't get frothy oil, oil in the coolant or coolant in the oil because the oil passages are still closed off from everything else.

The same for it just being blown and affecting oil.

Or affecting both oil and coolant.
 
Did he do a wet compression test? Did the readings come back to nearly normal?

A wet plug can be from a plug that isn't firing. The low compression can be from fuel washed out rings and cylinder. Have a harder look at an ignition miss, such as a bad coil or bad wire.
 
Jim,
if one wasn't firing, he wouldn't see smoke, right? Unless the fuel was being ignited in the exhaust somewhere but then that'd be black smoke for fuel.
 
69Boss302 said:
Jim,
if one wasn't firing, he wouldn't see smoke, right? Unless the fuel was being ignited in the exhaust somewhere but then that'd be black smoke for fuel.
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What is a wet compression test, is this when you put a small amount of oil in the spark plug hole and then do a compressioncheck?
 
Yes. Use about a tablespoon of heavyweight oil, 30W would work, dropped through the spark plug hole and do the test.

If you the compression goes up, the rings and cylinders could be the culprit. The oil will temporarily coat the rings and provide a seal.

If the pressure stays the same as before, the either the valve or headgasket is the problem.

Don't use too much oil for the test because that will throw off your results. You only need a little bit.
 
69Boss302 said:
Yes. Use about a tablespoon of heavyweight oil, 30W would work, dropped through the spark plug hole and do the test.

If you the compression goes up, the rings and cylinders could be the culprit. The oil will temporarily coat the rings and provide a seal.

If the pressure stays the same as before, the either the valve or headgasket is the problem.

Don't use too much oil for the test because that will throw off your results. You only need a little bit.
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Mechanic did that, and comrpession went to 75, then back down to 17, then back to zero!!
 
69Boss302 said:
so he put a little bit of oil in, rechecked the compression at TDC and it did not hold the pressure?
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All I know is that we put the small amount of oil in where the spark plug is, the valve cover was off, and we did three compression checks, and the first one was 75, then the second was 17, and then it was back to zero!
 
69Boss302 was extremely generous, and sent me fuel injectors. It appeared they weren't the culprit!


Is there any possiblilty that something with my wiring or ecu or something is not controlling the fuel injector properly? I changed fuel inejctors, and the misfire stayed on cylinder 5... so the actual fuel injector was not the culprit, but i suppose that whatever it is that controls it, if its malfunctioning, could be the culprit!
 
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69Boss302 said:
what were the numbers from the other cylinders on that same side?
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175 in cylinder 6, and 155 in clinder 4. And the first comrpession test we did on 5, before the wet one was 12! It was zero once, and then we did the wet test!
 
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