I have Tried Everything :( Please Help!

[madman_2]

if none of this stuff works... just replace the motor. some 2.9s dont last that long. she may have blown something internally.

 

[Bryan22]

He's got a 3.0 and they don't usually die. lol that's nott a good way to trouble shoot a problem unless u've got alot of cash and time..

 

[evanesce69]

if the fuel pump were taking a crap and it was running lean, wouldn't it throw codes to that account. He doesn't have any codes.

it may be possible to get to highway speeds, but the throttle needed to get there would be excessive. this may account for the transmission downshifting. lots of throttle and no go, the tranny would want to kick down thinking the driver was wanting to pass

 

[shadetree]

Does the truck smoke, and if so, what color??shady

 

[Dwright4]

The truck does not smoke at all..Never has. The fuel pressure was check twice and is 55psi at the rail. Even reving the motor to 4500rpms the pressure never drop a pound.The compression test has been done three times all with different results. First time it had no compression on 4or 5 then it was good on all. And now it is back to barely and on 4 & 5 .But it makes no sense because I can still drive 70-80 on the highway at about normal RPM's as long as it is flat as soon as the hill comes it falls down to 50 or so. But it shakes like crazy when in overdrive and at idle..And Yes We know how to do a proper compression test.
Thanks

 

[Just_Randy]

Valves sticking on 4 and 5??? Broken valve springs? Bent valves? Some reason you have compression some times and not others! Would a valve issue throw a code?

I think you're assuming "no-load" and "high-load" have the same affects on the engine. I don't think that's true. I'm pretty sure the fuel requirements are different under a decent load. And I think the valves act different as well. I would still be suspect of both.

 

[Quiksurf]

Fuel volume testing is best done under the condition that the engine is having the issue, if you issue is revving in the driveway, then its not it, but i would reccommend driving it with the fuel pressure gauge taped to the windshield. you can also try a running compression test. Try removing a single plug, install the compression gauge with engine running read gauge at idle, typical readings may be as low as 50% of static compression, but check all 6 cylindersand compare to each other. you shouldn't see more than 5-10% variation. running compression issue is normally a valve problem. at work we had about a dozen rangers with valve seat reccession issues requiring new heads or seats.

 

[Just_Randy]

I just happen to be reading on another site and stumbled on this, "Everytime you rev that engine past 5,500 RPM's you remove a slight bit of tempre from the valve springs. You MAY be able to rev at 6,200 (factory rev limiter is 5,800 max), but you won't be able to for long. You will not notice it, either, it will creep up on you and one day you will be struggling to pass a car on the freeway.
The factory valvesprings are weak and it takes some cash to get them up to par. The factory valves won't put up with it for long either."

Seems extremely likely here! As a matter of fact, I'm wondering if I might have a slight bit of valve spring issue.

 

[Big Jim M]

Golly Randy!

I just happen to be reading on another site and stumbled on this, "Everytime you rev that engine past 5,500 RPM's you remove a slight bit of tempre from the valve springs. You MAY be able to rev at 6,200 (factory rev limiter is 5,800 max), but you won't be able to for long. You will not notice it, either, it will creep up on you and one day you will be struggling to pass a car on the freeway.
The factory valvesprings are weak and it takes some cash to get them up to par. The factory valves won't put up with it for long either."

Seems extremely likely here! As a matter of fact, I'm wondering if I might have a slight bit of valve spring issue.

Your post sounds like a valve spring commercial.. I'm betting springs that are OEM can withstand factory maximum rpm for as long as aftermarket ones..
Somebody must have copied that post directly from a Compcams box..
Big Jim

 

[Just_Randy]

Hmmm... I guess its possible.... But there's a lot of grammer errors to be a direct copy-n-paste.

Don't springs wear out though? I know metal eventually fatigues and can break. 170,000 miles is a decent amount. I also know everytime I've had head work done, the head always comes back with those copper washers under the springs.

 

[Ranger44]

He could very well check for a valve leak......


Put a peice of paper, or dollar bill up to the tailpipe. If it is steadily blown from the pipe, things are most likely fine. If it's sucked towards the pipe at times, a sticky or worn valve may be suspected.

As for loss of compression, a blown head gasket, cracked head, or bent valve can be possible. IIRC, Wicked Sludge had one of the vavles bend on him on his #4 cylinder.

 

[Just_Randy]

He could very well check for a valve leak......


Put a peice of paper, or dollar bill up to the tailpipe. If it is steadily blown from the pipe, things are most likely fine. If it's sucked towards the pipe at times, a sticky or worn valve may be suspected.

I'm impressed! Great idea! How come I never think of these things? LOL

As for loss of compression, a blown head gasket, cracked head, or bent valve can be possible. IIRC, Wicked Sludge had one of the vavles bend on him on his #4 cylinder.

This is what happened to me last week. My bud decided to rebuild his 250cc atv. We took it apart, but he and another guy took the valves out. He got a new intake valve and I was the lucky guy that got to put it all back together. Well, here's where it gets strange.... The intake valve wouldn't go back in the guide! Neither would the old intake valve! Hmmm... So, I lay 20 questions on him. He said he never dropped it, the guy that helped him is a mechanic for one of these carpet mills around here, and the valve came out easy 2 weeks ago. WTF??? How would a valve guide just mysteriously and spontaneously deform right in the center like that? I usually have trouble with loose guides.... Not tight ones! But sure enough, right in the center of the guide is a tight spot. Viewable if the light hits it right.

 

[Dwright4]

Hello Again. Well I went out today and worked on the truck and tore the heads off and found that I have a Valve issue.The exhaust valves are past the seats on almost all cylinders.. So my question is now Buy a used set outta junkyard or have these ones repaired by a machine shop?. I went last week and bought a 2004 Ranger ext cab 4x4 same as my old one but only 40,000 miles with the 4.0 motor.. So I'm not in a hurry to get this done.
So anyone got a set for sale?
Thanks
Dave

 

[Ranger44]

If it were my truck I'd rebuild the heads that I have.

But, you should have them magnafluxed, etc, etc. Depending on how much the machine shop charges it'd be cheaper than a new set.

I'd compare the costs of new heads vs. the price to get them rebuilt. If the current heads are cracked.....then you'd have to add the cost of a set of J-yard heads into the rebuild costs.

 

[almostclueless]

Your post sounds like a valve spring commercial.. I'm betting springs that are OEM can withstand factory maximum rpm for as long as aftermarket ones..

I doubt that very much when it comes to pushrod engines.