Hello everyone. My name is Nick and I have a 95 ranger with a 3.0 in it. I have a no power under load situation. I can bring it up slowly sometimes, but if I jump on the throttle it won't go above +-2k. No change if I put it in neutral. I noticed after putting in my stereo, disconnecting the negative battery cable made it worse. I know that the computer needs to "re-learn" after disconnection, but maybe also a symptom? I know that 3.0's are gutless, this is my 3rd ranger! This is definitely something that got worse. I am not missing at all, spark plugs look fine. 180k on the truck, 90k on the short block. When I did that, I put a new clutch, egr valve, pcv valve, fuel pressure reg. and that might be it. Otherwise everything else is o.e. My tailpipe is clean, almost too clean...But my truck has run lean since I got it. No codes, had one about 5 months ago that was evap emission system, but it went away after clearing code. New fuel filter as soon as this problem arised, that was my first guess. I have a fuel pressure gauge, and am within Chilton and Haynes spec's. So, I am thinking possibly injectors? I tapped with a screwdriver on my cat and it doesn't sound plugged. That is probably not the correct test for it, but that's what I did. A bad shot of gasoline?? Also when this problem arose, it was when my father inlaw was driving it. I was in out of the state on a boat. Spark plugs and wires are under 40k miles old. I don't know what else I should list that is critical info and I am sure that I forgot some crucial info. But that is all I got for now. ANY help would be appreciated, you guys are pros!

 

This sounds like a plugged catalytic converter.

 

So, today I put new plugs and wires in the wife's 02 ranger. While I was doing that I cleaned her MAF. On a whim I decided to clean mine again, (it got cleaned when I noticed my current symptoms) and I got a big improvement. Not 100% but not bad....So, that's the newest. Maybe I will check my cat out next. But a big improvement none the less..

 

FWIW, I would have suggested cleaning the MAF, but then read that you had. I don't think a cat would plug up unless it had been mistreated. Did yours take a lot of crud from the engine running bad before?
The way to check is to take out the upstream O2 sensor, and put in a pressure gauge. I think a few psi max is reasonable. I think that when it is plugged, it would take a bit of time for enough pressure to build up that you would feel the power dipping as the pressure built. In other words, get it warmed up, and then turn it off. Let it sit so the pressure would have time to leak out, then start it up and get on the go pedal to see if it has a lot of power until the pressure builds. You would also note a reduction in exhaust coming out the tailpipe if it were plugged.
I don't know how you cleaned the MAF, but when I cleaned my wife's T-bird MAF, I took out the torkx screws, and took it apart so I could see the two wires. One had a speck of 'something' on it, which I cleaned with carb cleaner. Got rid of my CEL and codes.
tom

 

in live 25 miles out of town and cant really afford 100.00 per hour mechanics.so i bought a eqquis pocket scanner for 60.00.it has cd for a computer so i can look up the trouble codes saves a lot of frustation.
lrd56

 

Why do you people (not in a racist sense, rather referring to FTE members in general) always jump to that conclusion? Clogged converters only happen because the truck has been running like crap and was ignored long enough to toast the cat. Otherwise the converters lasts forever.

Plugged fuel filter or weak fuel pump or dirty MAF or plugged air filter are all far more likely culprits. Converters are only a conclusion to jump to when all other options have been exhausted.

 

KhanTyranitar my suspicion is based on his input and 45 years in the auto repair business. I didn't suggest he go out and replace the cat. I would suggest verifying it is either good or bad there are three ways to do that use a vacuum gauge a pressure gauge or take the cat loose and drive it. At higher constant rpm's the vacuum will just continue to drop off to near nothing instead of hold steady. A pressure gauge will show back pressure and on today's vehicles as little as 1 1/2 - 2 psi is indicative of a problem that will show up as a drive-ability issue. I have put new cats on they won't show any back pressure. While I don't really recommend removing the exhaust system (cat) as a test for fear of burning up the vehicle. I have seen it prove that the cat was the problem. The OP states that he feels it is running lean and has for a while if that is a true statement that in its self can melt a cat as well as running to rich or with a miss fire. It could have jump time but these have timing chains and they usually won't run after that happens. There is a real possibility of a large vacuum leak. But they usually cause a very high idle.

 

check the gas tank filler hose for cracks at the tank.if you have cracks
you have loss of pressure for your fuel pump.my ranger has cracks at the filler hose .i wrapped it with aluminum tape so far good luck.i wont spend 400.00 for one from ford
i havent found another source for one.lrd56

 

Cats don't last forever if someone has been using leaded gas. Who knows what the PO used?

 

Yeah, Bidwell, we can all find leaded gas at every corner. Not since 1974 or 1975, I forget.

Availability of leaded fuel is limited, I think, to aviation gas. Even NASCAR is running unleaded, and is planning in using E85, from what I read the other day.
tom

 

"Leaded gasoline will no longer be available in the United States after December 31, 1995. The Clean Air Act Amendments of 1990 mandate the elimination of lead from all U.S. motor fuel by January 1, 1996."

Leaded gasoline and the over-use of certain fuel additives can shorten the life of a catalytic converter.

A catalytic converter can also fail because of:

* Bad exhaust valves on the engine
* Fouled plugs causing unburned fuel to overheat the converter.
* A very rich mixture.

 

Couldn't you check the cat by just putting your hand over the exhaust tip? Maybe a fuel pump or main relay? Could the fuel press reg be installed wrong or faulty? Try starting it up with the stereo disconnected?

 

Yes, there has to be other problems present first, and they have to go on long enough to cause the converter to fail. Otherwise it will outlast the engine. These other problems cause a loss of power in their own right. So again, a plugged converter is a conclusion you come to when you have clear evidence that it is the case. Check all you filters first, check the fuel pressure and make sure it is within specs, make sure all tune up work is up to date. Make sure the MAF is not the problem either, a bad MAF can cause a severe loss of power.

If everything else checks out, then start looking at the cat. If the problem that cause the original cat to fail is not identified and corrected, it will do the exact same thing to the new one. This is exactly why the cat is the last thing to suspect, it can only be damaged by another problem, and it will fail repeatedly unless that problem is addressed.

My bet is that the MAF element is fouled. This is especially likely if you are using a K&N filter.