Did all injectors last week and it was clear for about a week and a half. Then it threw #6 again. Got a compression kit from Autozone and My numbers were 190 all around except 135 on #4 and 90 on #6. That explains the code for 6 and the one time random code after clearing the original #6.
So now I'm nervous thinking about head gaskets, piston rings, etc that are beyond my skillset.
the guy I use for harder jobs is booked 3 weeks out. Am I safe driving this thing with the low compression? I'd rather not have to take my 1 ton truck everywhere. It's a yard truck and it's not very nice on gas, and who knows how reliable it is driving for a month straight.
the guy I use for harder jobs is booked 3 weeks out. Am I safe driving this thing with the low compression? I'd rather not have to take my 1 ton truck everywhere. It's a yard truck and it's not very nice on gas, and who knows how reliable it is driving for a month straight.
You're fine driving it. You should find out where you are losing the compression by doing a leak down test before you pay a shop to fix the issue. It wouldn't be wise to pay for a rebuild of the upper or lower end of the engine if it's just a head gasket issue.
Here's a video that will help you out.
__________________ "My old man is a television repairman, he's got this ultimate set of tools. I can fix it!"
Leakdown eh? I'm at work and can't view videos. is that where you see if it holds the pressure?
If 6 was about half compression and 4 was also noticeably low, I'm wondering if it is the head gasket, worn between the two cylinders. Does that make sense? I'm trying to visualize the anatomy of the engine and that's something that links those two together in terms of proximity. Anything else I can do besides the leakdown to rule in or out other things? I'm glad I got a response from you Tim I use your videos all the time!
the guy I use for harder jobs is booked 3 weeks out. Am I safe driving this thing with the low compression? I'd rather not have to take my 1 ton truck everywhere. It's a yard truck and it's not very nice on gas, and who knows how reliable it is driving for a month straight.
Pefectly safe. I had 60 PSI in cylinder 6, so I decided to up the boost and run my supercharger at 11 PSI, then add water/meth injection and crank up the HP. No issues, well other than bad compression in that cylinder! Drove it that way for several years.
OK so I did the leakdown today and I got air slowly coming out of the throttle body...indicating intake valve? But wouldn't that be the valve cover gasket and air intake? I just re-did those AFTER learning about the misfire as I did the injectors. So that can't be the problem. I also thought I heard some air coming out of the tailpipe.
Furthermore, there was red crap on the front of the engine, making me think of burnt coolant. But no bubbles in the radiator top. This same red stuff was at the top of the driver side fuel injector wells.
So...I'm at a bit of a loss. And to double check if I was truly at the top dead center compression I followed the cues in the video and did it at the other top stroke just to see. And on the other stroke (presumably exhaust stroke) the air coming out of the throttle body intake valve was tremendous. It blew a latex glove right off (that's how I checked for leakage)
OK so I did the leakdown today and I got air slowly coming out of the throttle body...indicating intake valve? But wouldn't that be the valve cover gasket and air intake? I just re-did those AFTER learning about the misfire as I did the injectors. So that can't be the problem. I also thought I heard some air coming out of the tailpipe.
Furthermore, there was red crap on the front of the engine, making me think of burnt coolant. But no bubbles in the radiator top. This same red stuff was at the top of the driver side fuel injector wells.
So...I'm at a bit of a loss. And to double check if I was truly at the top dead center compression I followed the cues in the video and did it at the other top stroke just to see. And on the other stroke (presumably exhaust stroke) the air coming out of the throttle body intake valve was tremendous. It blew a latex glove right off (that's how I checked for leakage)
Yes, you are correct that if you hear air coming out of the throttle body it's getting past the intake valve.
If you've got coolant near the fuel injectors, your intake manifold gasket is probably bad. So, you might have a couple issues going on.
Taking the path of least resistance before pulling the heads off or contemplating an engine replacement, I'd check the valve clearances on the #4 and #6 cylinders and see if they are way off. Maybe a valve clearance adjustment could improve the loss of compression past the valve seats.
__________________ "My old man is a television repairman, he's got this ultimate set of tools. I can fix it!"
This is where having a boroscope is a really great thing. This could be a intake manifold gasket issue, or it could be a cracked cylinder head issue.
Pulling the manifolds, and replacing the gaskets is a fairly simple job, and not too expensive. If you have the time and tools, I'd suggest giving it a shot.
I did put new intake manifold gaskets on (plenum gaskets right?) as a part of my fuel injector swap. I did injectors, o-rings, plenums, valve cover all in one go.
I have one of those camera scopes you plug into the phone. What would I scope?
Drive the vehicle normally. Let it sit over night. Before running the vehicle in the morning, pull the spark plug from #6 and see if there is coolant in the cylinder. If so, you def have a leak in either the head, or head gasket for that cylinder.
Drive the vehicle normally. Let it sit over night. Before running the vehicle in the morning, pull the spark plug from #6 and see if there is coolant in the cylinder. If so, you def have a leak in either the head, or head gasket for that cylinder.
This is great advice.
For the intake valve, consider yourself lucky! Unless the valve itself it cracked, all you will need to do is swap out one shim on that valve. Hearing the air hiss in the crankcase is the worst case scenario, since that means your rings are tires and not holding compression. Intake valve is simple and you should gain most, if not all, of your compression back. Just take your time, get a copy of the FSM if you can and be patient. Getting the shim out with the pick tool is a little bit tricky.
I say that for 2 reasons. 1: I'm a retired mechanic. 2: This was a personal experience for me on my 4Runner. I too had a P0303 and P0300. Turned out to be a cracked cylinder head that was also warped. Apparently the PO had slightly over heated the vehicle before I got it, and there was no trace of that on Carfax.
I say that for 2 reasons. 1: I'm a retired mechanic. 2: This was a personal experience for me on my 4Runner. I too had a P0303 and P0300. Turned out to be a cracked cylinder head that was also warped. Apparently the PO had slightly over heated the vehicle before I got it, and there was no trace of that on Carfax.
Wow they must have fried the heck out of it. I can't remember the last time I saw a cracked 5VZ head.
scoped it today, both 4 and 6 were bone dry, at least where my camera could reach. I couldn't make it swivel around. The only red fluid I can find with my camera is by the water pump housing, and oddly enough like I previously stated by the fuel injector holes on the driver side. But coolant doesn't even go up there does it? Maybe it's something else red.