No gas pedal response

[Teresa R]

My 2004 3.0l ranger has no power going up a hill, I can push down on the gas pedal and it doesn't respond. Won't go over 2000 rpms. New throttle sensor, fuel filter and I checked the fuel pressure on the fuel rail and I'm getting 60 psi.

 

[RonD]

Welcome to the forum

Engines are self power Air Pumps
Air comes in, air filter
Is mixed with fuel and exploded
Then air goes out, exhaust

If you restrict Air in or Air out you will limit RPM and power
Thats the point of the throttle plate on gasoline engines, it limits air in so limits RPM, so engine can idle

A vacuum gauge($30) is a good tool to check an engine, like a pressure gauge for a pump
Engine should show 18-21" of vacuum with throttle closed

If you raise RPMs vacuum will drop but if you hold RPMs at say 1,500 steady, vacuum should come back to 18" and stay there, if its slowly dropping then clogged exhaust most likely, air can't get out

If air can't get out then new air with fuel can't get in, so loss of power and RPMs

 

[Teresa R]

Ok, my throttle body is VERY dirty. Could it be that? I don't think it's a clogged cat.

 

[RonD]

I doubt throttle body could get dirty enough to limit RPMs to 2,000, air filter could

No one ever thinks its a clogged exhaust, until it is, lol
Simpler test, pull out upstream O2 sensor from exhaust pipe
Start engine, it will be LOUD
REV engine
If it now REVs better and higher you have a clogged exhaust

I assume you have tried to REV engine manually from in the engine bay, so its not a bad throttle cable?

 

[Teresa R]

I put a new upstream 02 sensor in after it started doing this. It does great until I start up a hill, then it just bogs down. Thank you I will try that.

 

[Teresa R]

I'm sorry I should have been more clearer. It run fine gets plenty of gas, except going up a hill. Living in the Appalachian mountains that's a problem! Lol

 

[pjtoledo]

mountains? 3.0 engine ???????
how long have you had this Ranger, when did the problem start?

 

[RonD]

Good, 2 new O2 sensors
Pull them out, should be easy

See if engine REVs better with open exhaust ports, if so clogged exhaust

You say it won't REV passed 2,000rpm, which is different than "lack of power" in that no engine has power under 2,000rpm, not even a V12
So you don't have a "lack of power", you have "limited RPMs", which can be caused by partially blocked exhaust

And the 3.0l Vulcan engine is a HIGH RPM engine by design, has no power under 3,000rpm
Need to get this engine up to 3,500rpm to start getting power out of it

Limited fuel flow would cause ping/knocking as engine Leaned out, that wasn't mentioned and you would hear it

Too much fuel would cause smoke out the tail pipe, and you would see it, and no mention of that

 

[Teresa R]

mountains? 3.0 engine ???????
how long have you had this Ranger, when did the problem start?

6 yrs and I went and got groceries Sunday, ran fine. Started to work Monday and when I got to the first hill I have to climb it just bogged down and wouldn't pull it.

 

[rusty ol ranger]

The symptoms youre describing are classic clogged cat

 

[Teresa R]

It runs good when I start it. Revs up good, runs fine until I start up a hill then it loses power. No matter how much gas I give it ,it won't go over 20mph.

 

[rusty ol ranger]

It runs good when I start it. Revs up good, runs fine until I start up a hill then it loses power. No matter how much gas I give it ,it won't go over 20mph.

Thats because the cat probably isnt fully clogged yet, but its on its way to that. Going up a hill requires more power, meaning more fuel and air are getting pulled in and exploded in the cylinder, which means more needs to escape through the exhaust.

The cat is not plugged enough to choke it when the engine load is light, but cannot handle the extra flow when you start workingit a bit

 

[Teresa R]

Ok, I'll try to unstop it. Can't afford $1700 for a new one. Any suggestions on how to do that?

 

[rusty ol ranger]

Ok, I'll try to unstop it. Can't afford $1700 for a new one. Any suggestions on how to do that?

There really is no way besides replacement

 

[pjtoledo]

there really is no LEGAL way besides replacement

we can't talk about that option

however, if you were to replace the gasket between the Y pipe and the catalytic converter that would give you ample time for a test drive.
I'm up in the rust belt, those bolts are usually corroded beyond recognition. yours should be easier .

do you have a vacuum or pressure gauge?
there are 2 small hoses connected to the drivers side exhaust manifold.
hook the gauge to either one, plug the left-over end, the see what the pressures are when reving the engine.
and when hill climbing.