Bad engine

Thanks guys , inhad installed a new MAF when the thing went into limp mode after the first MAF went bad or at least I thought it had. I'm still going to take it somewhere else for a second opinion. I myself have a very hard time believing this engine was this bad. It never smoked and pulled a little 1200 lb teardrop camper all the time. Never even knew it was back there. Only reason I took the MAF out in the first place was just to clean it for better gas mileage.

 

Did they say what the pictures are supposed to be? Valves?

If they're scoping cylinders and saying the engine is bad then they should be doing a compression test with the plugs out.

 

So the only reason you pulled the MAF sensor was to clean it? Not because of a check engine light? Is there any chance they just got your truck / paperwork mixed up with someone else’s? None of this adds up at all.

 

@jackn7 Yeah it has had a check engine light on for over a year. Also yes the only reason I pulled the MAF was to clean it. As far as I could tell the truck was running fine before that. As far as paperwork there weren't any other Tacos on the lot. That's ok though now I have it at a place I trust. The other place was just a local shop. Now I have it at a guy who is a mechanic for Toyota that has a shop out behind his house and works on other people's vehicles on the side.

 

Those are pictures of an OHV engine.

 

So will we get to hear the rest of the story?


Threads like this serve the community well if there is resolution posted so they have ideas about approaches to their own problems.

 

@Clearwater Bill , Still an ongoing issue I have been told I need a new block by 2 different people but none of them have ever actually dug into the motor itself. Now I am sending my truck home with a friend of mine who is a mechanic to actually tear into it and see exactly what is going on. Stay tuned

 

Hey everyone just an update here is what they have found out so far.

I should have it back together buy then the spark plugs where not factory it has denso iridium plugs in it not what the book recommends for our trucks i puffer the factory denso Coopers they was all gapped at .44 like there supposed to be but number 4 was gaped at.45 and and cylinders 1/3/5 all had 195psi Is compression #2 had 200psi #4 had 180psi and #6 had 190 i have to run and get the timing cover inspection gasket tomorrow im going to inspect your timing chains and still need to pull the vavle covers to check everything on the vavles was going to make sure you wanted new plugs or not i did sand blast them clean like new again just copper plugs burn hoter witch meens a better spark theres so spark plug are on you if you want them replaced or not im going to go ahead and pull your lower intake and clen all of the carbon out of it

 

Got the truck back it's running but has a pretty bad knock. May end up getting a new motor in the end.

 

Maybe I didn't read closely enough. Did you have the knock before a bunch of people looked at? Because it sounded like things were OK other than the CEL?

 

I never heard a loud knock but was told by others that #4 valve was stuck.

 

If 1 if the 4 valves were stuck it would seem to be closed, as you had good compression on all cyl.

 

Is it even possible to have a valve stuck closed? Wouldn't the cam would force it open the next time the lobe came around? I could see the valve being stuck open on a non-interference engine and then it would run like it was missing a cylinder.

 

I understand your thinking.

But I dunno how you can have a open one and get the compression numbers he posted.

OTOH I dunno how a 'stuck valve' was diagnosed either.

Then again there are several unclear bits in this thread

 

Valve sticking usually means they hang up in the guide and don't close quickly after the cam lobe moves out of the way, especially at higher rpms.
A cranking compression test is done at (obviously) lower speed so it doesn't always appear on a compression test.

You'd expect some kind of nasty valve train noise though. And it will usually affect intake vacuum and show up as an erratic vacuum gauge reading at idle

 

+1

sticky valves usually are easy to spot with a vacuum gauge.

 

@04_Tacoma is it dead?