Hey Everyone, new here to the forums. Worked on the ranger this weekend and couldn't get it fixed so figured i'd come here for some advice.

I have a 2003 Ranger XLT 2.3L Duratec, 2WD 5Speed. 110,000 Miles.

I just bought the truck with 108k on it a couple months ago and changed the oil, tranny fluid, and rear diff fluid.

Its been driving great until last friday 3/3/17. On my way home from work the 3rd stop sign I got to it started idling like **** and going down to 400-500rpm and feeling like it was going to stall. When driving in 2nd-4th gear anything above 2k rpm it felt like nothing was wrong, not sure if it just felt this way or was actually fine. I made it home safely and then CEL popped on a few minutes before getting home.

Confirmed Codes:
P0316 - Engine Misfire Detected on Startup (First 1000 revolutions)
P0171 - System Too Lean Bank 1
P0301 - Cylinder 1 Misfire Detected

Pending Codes:
P2195 - 02 Sensor Signal Biased / Stuck Lean Bank 1 Sensor 1.

This is what I've done so far:

• Cleaned MAF Sensor
• Cleaned Idle Air control valve
• Replaced spark plugs
• Replaced spark plug wires
• Replaced ignition coil
• Checked cylinder compression - All four of them above 150PSI - Cylinder 1 is 155 PSI
• Checked Fuel System Pressure - 65 PSI
• Removed all fuel injectors, replaced o-rings and cleaned them, reinstalled them with cylinder 1 and 4 injector swapped to see if my misfiring cylinder would change.

Put everything back together, cleared the codes, started it up and still idles bad and the CEL came back with the same codes! P0301 and P0316.

The o2 sensor and lean code has not come back yet, but i think its because i need to drive more for it to come back. My next step is replacing the upstream o2 sensor which I believe is the bank 1 sensor.

Running out of ideas after the o2 sensor, any ideas?

Thanks for reading!

I hate car problems

 

Welcome to the forum

Yes, cars have become much more reliable with all the electronics added, which is why we hate problems now, lol.
In the old days we had to work on them monthly or weekly to keep them adjusted and "in tune", now we just turn on the key and expect them to work.
So having "a problem" is a steep learning curve because it is so rare.

4cyl engines only have Bank 1, V6/V8 engines have bank 1 and bank 2
Sensor 1 is upstream, closest to engine
Sensor 2 is downstream after Cat converter

So B1, S1 would be upstream O2 sensor on 4cyl engine

P0316 is random misfires
P0301 is cylinder 1 misfire

2003 2.3l duratec engines used IMRC, intake manifold runner control, which was dropped in later years.
It is vacuum controlled and when failing can cause your symptoms.

Google: ranger 2.3l imrc

And also: Ford Ranger code p1537

Your IMRC valve(electric solenoid) is probably OK because if it was bad that would cause its own code.
But the vacuum hoses connected to this valve(lower drivers side of engine) and the IMRC actuator(upper rear of engine) are probably broken or cracked, which was a known issue
Leaking vacuum hose will cause Lean code and non-working IMRC will cause low RPM misfires

 

I replaced the upstream o2 sensor #1 and nothing changed.

Checked both vacuum lines connected to the IMRC valve and and they both look great. How many vacuum lines connect to the actuator? I couldn't find it, any tips?

Any other ideas for a solution? Not sure what to try next, if I cant figure it out what should I do next? Local mechanic? Is a Ford dealership a bad idea? Just scared to bring to a mechanic because the issue could be many different things so I can imagine it will be pricey for diagnosing.

 

wonder if this would fix my issue like these guys https://www.ranger-forums.com/dohc-2...-rough-128852/

That plug on the intake manifold. Checking this next...

 

Wow.. It was my issue!!!! I just used a flash light down the crack between the power steering pump and the intake manifold. I can see the little cap that blew off the intake manifold its sitting in the pocket below where it popped out.

I sprayed air intake cleaner in the crack and my RPMs went right up everytime I sprayed.

Looks like ill be taking the manifold off tomorrow to plug it up!

 

Does anyone know how I can get my power steering pump off? I cant get the bottom left bolt that's directly behind the hard metal tube connected to the pump. Do i need to pull the pulley off first??

 

Good work finding that, hadn't read about that problem before.

Sorry no help on the PS pump removal

 

Just to update this post -

I didn't have to remove the entire intake, I just had to remove the power steering pump and then had enough access to replug the hole.

I used the original cap that blew out, used an epoxy to put it back on. It is now rock solid and I reinstalled the power steering pump.

After waiting many hours for it to fully cure, started the truck up and its running great! Back to normal, seems like its actually running a bit better. Probably from all the new installed parts from diagnosing the issue.

WOO!!!! So happy