Rough idle/hesitation/pinging?

[cp2295]

It means computer and IAC are working.

When you unplug the IAC the computer would see some change in idle, it would go down, it might be slight but computer is using the Crank position sensor, so more accurate than your senses, lol.
It would then try to open the IAC valve a bit to get idle back up, but IAC is not connected.
So when you plug IAC back in it would get that voltage signal from the computer and open up, so idle would go up.

Yes, I would look for a vacuum leak, and check the throttle plate to make sure it isn't sticking a little so not closing all the way.

The IAC is not a sensor it is an electric valve, computer opens and closes it each time you start the engine, just to test it.
When engine is started hot or cold idle should go up to 1,500+ RPMs then come back down to cold idle, 1,000 rpms, or warm idle, 750 rpms, that's the computer testing the IAC Valve.

Got a leak test done.. Smoke poured out of the iac valve.. Gonna replace that and report back!

 

[RonD]

Smoke should come out the IAC valve, it is a "controlled" vacuum leak.

 

[cp2295]

Smoke should come out the IAC valve, it is a "controlled" vacuum leak.

Yeah the guy said that but he said it's way more than normal and it was coming out of the wrong spot on the iac valve

 

[gatordog]

What

Already replaced that..

My Ranger exhibited those problems when my DPFE sensor went bad (DPFE going bad = common on the 3.0 engine), so that's something you may want to check into.

What in the world is a DPFE (diesel particle filter element?)and where is it? I have a 2002 3.0 with No EGR and it also has a ruff idle. I have replaced the upper intake o-rings, cleaned the IAC and throttle body, new plugs, new wires and the truck was just service with new fuel filter and coil pack. I also ran a compression check and all cylinders have good readings.

I have, but not replaced the cam position sensor and cam/oil pump drive.

I was also told it could be the CATS

 

[stmitch]

What in the world is a DPFE (diesel particle filter element?)and where is it?

Current diesel powered trucks use a DPF (Diesel Particulate Filter) as part of the exhaust catalyst in order to meet emissions standards.

Ford vehicles (atleast the ones with egr) used a DPFE (Differential Pressure FEedback) sensor. It's a small rectangular sensor that is bolted to the front of the upper intake manifold, to the left of the throttle body. Pics here: http://www.ford-trucks.com/forums/570551-ranger-3-0l-component-locations.html

 

[gatordog]

Idle

My truck does not have that DPFE think, but I still have a ruff idle. I will keep trying to fix and will update if I get it fixed.

 

[cp2295]

The dpfe sensor is on the front of the intake manifold with two lines going into it along with an electrical plugin.. It's black and rectangular.

Have you:
searched for a vacuum leak in the lines?
cleaned the maf sensor?
Checked evap emissions things to see if they're dirty?

O2 sensor can cause it but should throw a code, same thing with maf sensor but it's really easy to clean whereas an o2 is pretty much not cleanable and sucks to remove all 3 (or 4)

 

[cp2295]

Also the iac might just need to be replaced, when you cleaned it did you check to see its working? It should make a twang noise when you smack it on the palm of your hand (hit your hand with the side that touches the intake manifold/TB). If it's stuck then it won't work.. Plus mine has a giant vacuum leak so that might be an issue with yours. I'm pretty sure mine is some cheap aftermarket brand so if yours is motorcraft it probably won't have that issue.

And what is CATS? Catalytic converter? That shouldn't cause it, you'd have worse issues if that was clogged

 

[gatordog]

ruff idle

I have cleaned the IAC and if you unplug it the motor idles lower, so I guess it is working, but it could have a problem. It is made by Motorcraft and looks factory. I have checked for vac leaks and like I said new fuel filter, new wires/plugs and new coil pack. I did notice while it was running my arm got close to the coil pack and I got hit pretty hard with a good shock. The coil pack was installed by the dealer i bought it from, and it was a Ford dealer, so not much faith in those bastards.

How do you check the emission system for problems?

FYI my truck does not have a exhaust mounted EGR, and I don't have the DPFE either.

 

[cp2295]

Well in the evap emissions system there is a charcoal canister, purge valve, and a couple other sensors.. A quick google search will show everything.. Those two are the main ones though, and cleaning those out with some carb cleaner isn't a bad idea (somebody correct me if I'm wrong!!). I know my old jetta idled bad and I cleaned both those things and it definitely helped.. I'm gonna clean the charcoal can on my ranger tomorrow and I'll let you know if this helps my idle. The canister is above the spare tire, and purge valve is on a bracket on the drivers side of the engine

 

[cp2295]

I did notice while it was running my arm got close to the coil pack and I got hit pretty hard with a good shock. The coil pack was installed by the dealer i bought it from, and it was a Ford dealer, so not much faith in those bastards.

Damn bastards!!

 

[stmitch]

I did notice while it was running my arm got close to the coil pack and I got hit pretty hard with a good shock.

This is not normal. There's either a bad connection at the coil pack,a flaw in the coil pack itself, or there's an issue with a plug wire. Any of those three would cause idle/driveability problems.

 

[cp2295]

This is not normal. There's either a bad connection at the coil pack,a flaw in the coil pack itself, or there's an issue with a plug wire. Any of those three would cause idle/driveability problems.

+1

 

[RonD]

This is not normal. There's either a bad connection at the coil pack,a flaw in the coil pack itself, or there's an issue with a plug wire. Any of those three would cause idle/driveability problems.

Yes, electricity is quite predictable, like water always flowing downhill, electricity will always take the easiest path to a Ground.
Your arm became the easiest path.

If you were sweating and your hand on that arm was touching a metal engine part, then it could have been an easier path than the spark plug wire and spark plug, but there are a few "ifs" there.
Worth checking all connections for sure.

 

[cp2295]

Alright so I got the charcoal can off.. I am stumped by how it works now, or if I'm missing a hose. So on the end of the canister there's an elbow with a hose that connects to that, that's all fine and dandy.. Then there's a little black box mounted on the canister. It says "to canister" with an arrow pointing to a hose that goes into a T where it meets up with the charcoal canister and an electrical sensor. Now my concern is that there is a nipple on the other side of the black box where a hose looks like it should go, before the "to canister" sign. There was no hose connected and I looked around and didn't see one. It has no screen or anything on it so it's easily sucking in dirt and debris.. As far as I know I thought this emissions system was a closed off thing so now I'm very confused.. Is something missing?