Loses power over 15 mph

Welcome to 2CarPros.

Since you replaced the head, I suspect a couple possible issues. First, are you certain the timing belt was installed correctly? Second, have you checked compression to confirm that the new head and gasket are good? Have you confirmed there are no major engine vacuum leaks? And lastly, are you sure the catalytic converter isn't plugged?

Here are links you may find helpful. Take a look through them.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

https://www.2carpros.com/articles/symptoms-of-low-compression

https://www.2carpros.com/articles/how-to-test-engine-compression

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

The two pics I attached are related to timing the engine. Confirm that is where the timing marks were when you installed the belt.

Let me know if this helps and what you find. If you have other questions, let me know.

Joe

What is that?? Wq??

Welcome back:

I'm not sure I understand. What do you mean by Wq?

It sounds like a timing issue. It doesn't take much, even a single tooth off can cause power loss if it's changing the valve overlap timing. As Joe said run a compression test and see what the numbers are. Also verify the timing is correct on the belt. Lastly, what year did the replacement head come from?

Yes, I checked the timing three times and it's has 165 psi compression across all four cylinders. i used a cigar to check for vacuum leaks and I pulled the O2 sensor to see if that would help but nothing changed. when I try to climb a hill or accelerate to get to highway speeds you can smell the gas like it's running rich. I replaced all the gasket required to do the head.

The replacement head came off of a 1996 Ranger from the looks of them the only difference was where the coil packs mounted to it.

Okay, the interchange shows that 1989 to 1994 the head is the same. Then 1995-2001 is different. That could be where the problem is. Looking at the part numbers for those two years the casting numbers are different but nothing really says what they changed. The cam shows the same part number across those years but the valves don't. Fuel smell could be a bad injector or not fully seated, either of which can cause a power loss on a small engine. What parts off the replacement head did you use?

Just the head and cam.

Today I'll get a video and show you guys.

It feels like it's running a little better, but I do not know why.

Wow! It sounds like you are losing spark or fuel. Are you located in CA? I know there are differences in the ignition system designs. One will have a cam sensor and the other not. Also, there is an ignition control module. Have you done anything with that?

Run a fuel pressure test. Should be 30-40 PSI engine running, 30-45 key on engine off. Also pull the vacuum line off the regulator and see if you have vacuum and check that no fuel is there in the hose.

I have not done anything with the ignition module. I understand they can be expensive and I have vacuum to the fuel regulator but I popped the hood and the regulator looks like it has gas or oil all over it which wasn't there when I swapped heads.

And I'm in Oklahoma and it is a Oklahoma truck. it was bought brand new by my boss and I bought it from him because he didn't have the time to fix it.

I have a 1999 ford ranger xlt with a 2.5L 5 spd. It has me stumped, Its had a full tune up, checked the fuel pressure, replace both coils, timing belt replaced,replaced mass air flow and o2 sensors and reset the computer. Te check engine light is on and the abs light comes on spontaneously. The truck idles and starts fine but when u accelerate it has no power if you make it to 4th while driving you start to loose speed.. I need help1

id first read the codes and then id check the charging system. then id check the timing belt. they should be replaced at every 60000 miles as a rule. slack in the timing belt will cause loss of power like youre experiencing but not the abs light. that's why I said to check the charging. it can cause the two lights together if your voltage is dropping just below 12 volts

have the codes read and post them hear,have the battery and alternator tested also and post those results.also it is possible that you have a restricted exhaust system due to a broken or melted catalytic converter,or a crushed or bent pipe.

When you plug it in it does not register...it says... please connect vehicle.

All of a sudden one day while driving my 1998 Ford Ranger pickup with about 193,000 miles on it, the truck seemed to lose power when going above 55mph. It also began to almost "rumble" when you tried to accelerate. Putting the pedal to the floor you can only get the truck to go about 70mph if you're on a flat surface. Previously you could be driving 85mph and still pass someone with no problems (our speeds here on 75). Oddly, if you slowly accelarate it doesn't seem to rumble, but it will rumble if you start to go up a hill. It has a manual transmission, and pretty much cannot be driven in 5th gear because it has almost no power and rumbles when you hit the gas. However, if you put it in 4th gear you get a lot more power and it acts like it is in 5th gear. However, the rumble is still there when you accelerate. If you're driving on side streets it seems to run just fine. It feels like it's starving for gas to give it more power, but I'm no expert.

I took it in to my mechanic and he replaced the fuel filter, which he said was completely clogged. This didn't seem to help at all. He checked the catalytic converter, and he said that was fine. He also tested a few more things that showed a bunch of different pressures were fine. When he hooked it up to a computer nothing came up. I changed the air filter recently, and on reexamination that seems fine. The truck was running great before this and was previously owned by a mechanic. It seemed like theproblem occurred all-of-a-sudden. My mechanic said he doesn't think the problem will leave me stranded and that it is probably just a "tired engine" but I don't know if I'm willing to accept that answer. Everything else about this truck is great and even with the high mileage I think it has a lot more left.

Two things he suggested were changing the spark plugs (which aren't awful, but also could stand to be replaced) and the u-joints (to get rid of the rumbling, which I'm not as concerned about as just getting the power back). Could the spark plugs be what is causing the lack of power in 5th gear? Since there are 8 spark plugs (on a 4-cylinder) and it's very labor intensive on a Ford Ranger, it is going to be expensive to do that, and this truck is more or less just used to haul light loads of things from time to time. Not something I want to invest a lot of money in, but also enjoy having as a second vehicle.

Could it possibly be the fuel pump? If so, is that an expensive fix and/or worth it on a truck of this age?

Last major tune-up?

Lets get this three checked out the throttle position and the output shaft speed sensor and fuel system pressure and comeback with the results.

Sometimes a sparkplug will function perfect at idle but when at higher speed it starts to breakdown such as incorrect heat range/deposits/wide gaps

Get that looked at and the other areas I've mentioned.

i have a 1999 ford ranger with 162,000 miles and in the last week when i go up hills and it wants more power to get to the top the check engine light blinks and it feels like it wants to stall but when i get to the top and level out the light stops blinking and it runs fine i had it checked and they said the only code is the #1 cylender is not firing i just change the plugs and wires 2 months ago could that plug or wire be bad already and would that cylender not fire make the truck do that on hills if you can simplifiy this for me i would greatly appriciate it

Yes, that would definately make it run bad. Make sure the plug wire is on the distributor cap and the spark plug correctly. Take a look inside the wire at both ends and make sure the connector is not damaged. You should fell that little click when putting the wire on the distributor and spark plug. Buy a spark tester, they're cheap and plug it in the wire to check for spark at the plug. Also, check the spark plug for any hairlne cracks in the porcelain.

Welcome back:

I have to be honest, I don't feel it is a plug wire. Interestingly, in your video there was no backfire after it started running again. If it was a loss of spark, I feel you would have a backfire when the spark returned because the injectors would still be fueling the engine. With that, my next suspect is a camshaft position sensor. I asked your location because the CA emissions ones don't have the sensor. I attached a picture of it. If fuel pressure is good (however you need to confirm what is leaking on the regulator), it seems that something is shutting down injection. That is why leads me to the sensor. The cam sensor on this vehicle signals the ignition module for ignition timing. If I recall correctly, if there is no signal, the injector pulse is lost, too.

I attached two pics. One is location of the cam sensor and the second a portion of a wiring schematic. Locate the sensor and confirm proper connection, eliminate any corrosion, and make sure the pins in the connector are not damaged.

Again, in your video, the engine basically seemed to shut down and then pick back up again. That isn't a loose plug wire.
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You are starting to get a lot of feedback from people. If you have the chance, check the sensor and let me know what you find.

Take care,
Joe

Ok thank you @joeandnickolas I'll definitely check for a cam sensor I do remember unpluging anything like that on my head or the new head I put on so I will have to see but right now it is raining here an I tested the icm and it is working fine according to the testing

Welcome back:

Sounds like a plan. Let me know what you find. Also, am I correct in saying the engine shuts down for a second or two before it starts picking back up?

Joe

Yes you are correct. if I push in the clutch it will come right back to idle but if I just let it do it's thing it will do as you seen it's like it is hitting a spark cut or fuel cut. I have been around cars all my life and I have never seen anything like it. I work at a auto resto and my boss has no idea why it's doing it or what is causing it. he is the one that helped me swap head and he has been in the car business all of his life. so I'm dumb found I really do appreciate everything you guys have suggested, but I can't afford to keep dumping money into the truck.

When you check the fuel pressure I would also take it for a drive where you know it will cut out. See if it changes. Unplug the regulator and plug the vacuum line, start the engine, any fuel showing on the regulator vacuum connection?

I'll try that also if I can't find a camshaft position sensor but I still able no way to test fuel pressure. I'm going to get a new regulator from my grandpa he ordered one when i told him about what it was doing.

So there wasn't a cam shaft sensor there it's just the distro dummy shaft, but I did notice that my alternator wire was loose and for some reason it drained the battery overnight which I haven't had any problem like that since I bought the truck.

Have you repaired the alt wire? Did that make any difference?

Yeah, I repaired it but apparently the alternator is shot, so now the truck won't say running for more then ten minutes before it drains the battery.

You know, I wonder if that was the problem the entire time. I'm not sure why it is draining the battery unless a diode is bad or there is a short. Do me a favor. Follow these directions for testing for a battery drain. Check with the alt attached and then disconnected to see if that is the source of the draw.

https://www.2carpros.com/articles/car-battery-dead-overnight

Crazier things have happened. Maybe low voltage was the problem the entire time.

Let me know.

Joe

It was not the alternator, but I did cut the catalytic converter off and you can hear it pop when the truck comes back to life. so does that mean something to do with spark?

Welcome back:

It could be either. If you have a popping, it is an indicator that ignition is starting to occur. If it loads up with fuel, I feel you would hear a backfire.

Well it's not my problem anymore. my boss had sold me the truck on payments and since it didn't want to run right he took it back and fired me.

That's a harsh form of treatment. Sorry about that.

Oh I'll be taking him to court. I had paid him $2,000.00 put of $3,000.00 for the truck. but I really believe it was the CKP being miss aligned or something like that because it was a slight back fire when it would come back to life.

Good luck. When you get things straightened out we'll be here.