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3.0L 2003 Ranger 3 cylinders Misfiring i need some help please


Right 😂 I am hoping for valves because I can do that, piston rings on the other hand are a bit harder I’m only 16 and I don’t think I’m mentally prepared for piston rings also the shenanigans Intail reving, burnouts, flooring it, and going way to fast for the poor 3.0
I don't recall anyone talking much about "easy lessons.". All the lessons will make you a better mechanic though.
 
Right 😂 I see all this as a learning experience a what a great truck to learn on might I add but from here anyone have any advice on what my next move should be pulling heads ? Um defenetly taking the valve covers off at least.
 
remote possibility/long shot

are you sure the compression tester sealed properly to cyl # 3?
on a 3.0 the channels for the spark plugs is quite narrow and an adapter is needed on some of the hoses for certain compression testers.
however, since you just mentioned shenanigans I doubt this is the case but it is worth mentioning.

the 3.0 is a very simple & basic engine, and the pass side valve cover is easy to get to.
even pulling the intake to access lifters is not that bad.
if you have a bore scope it can be used thru the spark plug hole to see the valve action. don't stick it in too far and crush it with the piston.
 
remote possibility/long shot

are you sure the compression tester sealed properly to cyl # 3?
on a 3.0 the channels for the spark plugs is quite narrow and an adapter is needed on some of the hoses for certain compression testers.
however, since you just mentioned shenanigans I doubt this is the case but it is worth mentioning.

the 3.0 is a very simple & basic engine, and the pass side valve cover is easy to get to.
even pulling the intake to access lifters is not that bad.
if you have a bore scope it can be used thru the spark plug hole to see the valve action. don't stick it in too far and crush it with the piston.
Ok that’s good news because it looks like I will have to take that pas head out to examine or rather the valve cover also no bore scope unfortunately I wish I had one then I could see inside and even the cylinder walls.

also yeah I threaded the compression tester in with the same adapter like the rest and they worked so 3 just has no compression for some reason but yeah thank you you all have been very helpful so far. And a lot of great tips and tricks shared
 
you can put a hose to the plug hole and inject pressurized air. (before anything is removed)
if it comes out the intake or exhaust that valve is gone.
if it comes out the oil fill hole the piston is gone.
if it doesn't come out anywhere the valves are sealing and the piston is probably OK. that means the intake is not opening.

stick your finger in the plug hole and crank the engine.
if you get a suck-push-suck-push the cylinder is sealing and valve actuation is the problem.

the rusted & ready to break exhaust bolts will be your worst problem.
these engines have roller lifters, if one has rotated in its bore the corresponding camshaft lobe gets wiped out.
 
you can put a hose to the plug hole and inject pressurized air. (before anything is removed)
if it comes out the intake or exhaust that valve is gone.
if it comes out the oil fill hole the piston is gone.
if it doesn't come out anywhere the valves are sealing and the piston is probably OK. that means the intake is not opening.

stick your finger in the plug hole and crank the engine.
if you get a suck-push-suck-push the cylinder is sealing and valve actuation is the problem.

the rusted & ready to break exhaust bolts will be your worst problem.
these engines have roller lifters, if one has rotated in its bore the corresponding camshaft lobe gets wiped out.
Wow ok thank you that’s a lot to take in but I will cunduct all these test, also what do you mean by exhaust bolts like valve exhaust bolts ? Also I am pretty sure it has to be something with the valves because of the clicking I hear from the valve cover hopefully.
 
right and by catastrophic what are we looking at valves, rings and what else possibly

As others have said:

Valves, Rings, Piston, Connecting Rod, Push Rod, Head+whatever hit it, Block (Cylinder wall) + whatever hit it, etc etc - the list is long.

Rings don't just go out suddenly unless you are nitrous injecting or had something that otherwise put huge huge load on a barely hanging on set of rings.
Probably not rings, you would have "some" compression even with pretty miserable rings.

I don't want to be the bearer of bad news but zero compression on any cylinders is bad news. I'd double check all cylinders because if any are zero, you're going to have to start digging in.

Do you know the history on this engine? Was it running properly recently?

"bad" here is not all that relative... zero compression means this structure which is designed to hold high pressure has a hole in it.
I would NOT check compression till you figure out what is going on with cylinder 3.

Things that make a hole in this otherwise airtight object are either ruined engine or not ruined engine obviously, not ruined is 2 or 3 things long, ruined is 2 or 3 pages long.

If you are really LUCKY, a valve is stuck open and that is like super ridiculously lucky (no damage at all yet).
Kinda lucky a valve has dropped out of the keeper and is bouncing around - and you haven't ruined everything yet. (that valve will be bent and definitely ruined.
Neither of these are definitely a new engine / complete rebuild.
It gets worse from there..

Everything else that I can think of that causes zero compression is pretty catastrophic and will get worse the more you crank/run.

If you keep doing things like cranking / compression test etc you very likely will ruin the head/block whole shootin' match.

Stop everything and take a valve cover off to see if you don't have a bore scope and can diagnose.
I will even go so far as to say do not bump the engine to open the next valve so you can peer down with a scope - put a socket on the end of the engine and turn it by hand. If it is damn hard to turn, don't force it.

In your peeling out and rev-ing and and if you really really wrapped it up, that is when a keeper will fly loose and you end up with a bouncing loose valve.
 
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I also would not do the old suck/push test with your thumb - older engines had a lot lower compression and you could do that... a new high compression engine has enough suck power to pull your thumb in if you get a really good seal.
 
As others have said:

Valves, Rings, Piston, Connecting Rod, Push Rod, Head+whatever hit it, Block (Cylinder wall) + whatever hit it, etc etc - the list is long.

Rings don't just go out suddenly unless you are nitrous injecting or had something that otherwise put huge huge load on a barely hanging on set of rings.
Probably not rings, you would have "some" compression even with pretty miserable rings.



"bad" here is not all that relative... zero compression means this structure which is designed to hold high pressure has a hole in it.
I would NOT check compression till you figure out what is going on with cylinder 3.

Things that make a hole in this otherwise airtight object are either ruined engine or not ruined engine obviously, not ruined is 2 or 3 things long, ruined is 2 or 3 pages long.

If you are really LUCKY, a valve is stuck open and that is like super ridiculously lucky (no damage at all yet).
Kinda lucky a valve has dropped out of the keeper and is bouncing around - and you haven't ruined everything yet. (that valve will be bent and definitely ruined.
Neither of these are definitely a new engine / complete rebuild.
It gets worse from there..

Everything else that I can think of that causes zero compression is pretty catastrophic and will get worse the more you crank/run.

If you keep doing things like cranking / compression test etc you very likely will ruin the head/block whole shootin' match.

Stop everything and take a valve cover off to see if you don't have a bore scope and can diagnose.
I will even go so far as to say do not bump the engine to open the next valve so you can peer down with a scope - put a socket on the end of the engine and turn it by hand. If it is damn hard to turn, don't force it.

In your peeling out and rev-ing and and if you really really wrapped it up, that is when a keeper with fly loose and you end up with a bouncing loose valve.
Wow ok so what I got from this is don’t start it anymore pull the valve covers off and see in there also turn engine by hand. I am at least glad it’s not a piston rig but I am hoping it’s not the piston it’s self and or block or cylinder walls but I am hoping it’s all in the valves and that’s why I hear that clicking. Also if the block was cracked how would it run would it start at all and or would I even have compression in other cylinders? Also thank you for the advice
 
I also would not do the old suck/push test with your thumb - older engines had a lot lower compression and you could do that... a new high compression engine has enough suck power to pull your thumb in if you get a really good seal.
ah, no.

at atmospheric pressure and considering the square area of the end of a thumb it's less than 5 pounds of pressure assuming a perfect seal.
 
also the shenanigans Intail reving, burnouts, flooring it, and going way to fast for the poor 3.0

i call nay on this!

i do all those with my 3.0 and its still going strong at 220 or 225k miles. no smoking, no leaking, no issues at all.

so you are good to continue shenanigans as previously scheduled once your truck is back up and going.
 
i call nay on this!

i do all those with my 3.0 and its still going strong at 220 or 225k miles. no smoking, no leaking, no issues at all.

so you are good to continue shenanigans as previously scheduled once your truck is back up and going.
right that's what I'm saying she is only at 132k so this shouldn't be a problem my best bet is a valves is loose ore a lifter isn't sealing the valve anymore but I will keep y'all posted on my endeavors and maybe even some pictures
 
No compression is very odd. Low - yes. None - most unlikely unless it broke a piston, valve spring, or the like but check the other cylinders as well as suggested.

By the way, 16 is a great age for doing all this. You can crawl in there, under there, etc. and not pay for it like us old geezers.
 
but you pay for it that evening when your wrists hurt
 

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