94, E150, club wagon, 5.8. E4OD (226,400) miles. Passed smog easily in august.

Still have a slight rough idle, when the engine is hot. It idles great when cold, Runs fine while driveing but does feel a little sluggish.
Its kind of showing the same symptoms of the bad ICM I had before, would stall at idle when hot. After I installed a new one, the stalling completely went away. That was about 3 years ago (maybe) ?

I am also not getting very good gas mileage based on the history of my fueling routine.

Sunday when I came to a stop it felt like it wanted to die, but did not. When idleing if I punch the gas then take my foot off it almost wants to die, but does not.

So, Ive had the vacuum leak at the brake booster fixed, with a new booster.
I just had the plugs, wires and coil replaced. Plugs looked very good.
had IAC valve and ignition control module, dist. cap and rotor replaced about 2.5 years ago, maybe 3. Installed new air filter and just had oil/filter changed.

I am thinking maybe MAP sensor, Clogged fuel injector(s), fuel filter, pip sensor, or EGR. (Because these are all original, except fuel filter)

Questions:
Which one of the above would create a rough idle and cause the engine to want to die at idle?
Which one of the above are all or nothing, meaning they either fail or dont.

I could do the MAP and the EGR. pip and fuel injectors are another story, this being my daily driver.

Or, if you`ve got a suggestion as to what might cause the aforementioned issues I am all ears, Thanks.

 

Are you getting any codes?

I had something similar. It threw a p0171 and p0174 codes.

 

Nope, no codes. I have OBD1

 

Did you use a motorcraft ICM? is yours remote located or on the distributor?

Mine has not idled exactly right almost since I bought it. It doesn't try to die but just not right sometimes.. I don't get any codes either. My fuel mileage is also bad. I have changed the FPS, MAP, EGR,TPS, complete tune up, removed the upper intake and cleaned it as well as the throttle body while I had it off...

I have read that a O2 sensor can be going out and not throw a code but cause rough idle as well as bad mileage... I have a new Motorcraft O2 sensor but just haven't gotten around to changing it.

I don't recall seeing any posts in the forum about the engine temperature coolant sensor, not sender. but the one that feeds info to the ecm... I know on the GMC I had, that was a common issue and caused it to run rich as well as bad idle after the engine warmed up..

So that is a couple of things to think about..

Hopefully I will be changing out my O2 sensor by the weekend and I will let you know if that helps with mine.

 

Hi,
I would suggest to check inside the ECU and take a look at the capacitors.
There is one capacitor that goes bad. If indeed one capacitor has gone bad(leaking capacitor), you will notice the tar- looking stuff at the base of the capacitor.
If that is your problem, replacing the bad capacitor is an option or you can buy a new ECU if you have have the means to do so.

Good luck.

 

Anna, I did not install a MC ICM, I wish I would have. Mine is mounted on the drivers side fender.
I just passed smog in august, I would like to think the O2 sensor has not failed since then but obviously its possible.

Handy, Yes I have already switched out one of the capacitors, I checked the others about 4 months ago and they are good, but thanks for the tip.

 

Well in case you need it,, Motorcraft #F1PZ-12A297-A replaced by 5U2Z-12A297-D
Always double check the part numbers... I wasn’t sure what transmission you have so I just selected one and that may make a difference
I have found when looking for pricing, If you search with the old part number by itself and then the new part number by itself, you stand a better chance of finding a good deal..
Here is a new MC for $50
https://www.ebay.com/itm/Ford-F1PZ-1...1Z3YP0&vxp=mtr

If you haven’t already, here is a thread by Jeffreyclay with simular problems but had codes..
https://www.ford-trucks.com/forums/1...endations.html

His 94 is a 5.0 and he has a MAF..while I believe you mentioned MAP sensor. My 88 has a MAP and I thought most of the 90's had MAF?

 

We can help with a new ECU, give us a call. +1-888-875-2958 A capacitor change would be cheaper, though, so check that route first.

 

I installed a new PCV valve and grommet today. Oil was seeping pretty bad through the grommet and the PCV valve was very old and had a little oil in it.
Got both MC from dealer. Im done with aftermarket or house brand junk.
Probably a minor vacuum leak,

Anna, Thanks for the info.
Cccx, Dont need one now but when I do I will keep you in mind.

 

1994 E150, Club wagon. 5.8 E3OD Over 226,000 miles

So, I went on a long trip today and the van ran ok, but has a noticeable lack of power when accelerating on the freeway.
Just a year ago I could cruise at 60 and hit the gas and it would accelerate very good.

I used techron injector cleaner a few times in the last few weeks thinking maybe an injector is clogged but did not see any change, I may keep up with it once a month or so.

I also plan on replacing the fuel filter, fuel pressure regulator and, EGR valve.


Another issue I just found, is a fluttering sound when accelerating just like an exaust leak but I dont think I have one because it passed smog recently with good numbers.


Performed recently:
new pcv valve and grommett
new spark plugs and wires
oil change and filter
new brake booster
new ignition coil

About 3 years ago:
new Ignition Control Module
new Idle Air Control valve
new cap and rotor
new radiator and hoses

Any ideas ?

Thanks.

 

Today I poured in another bottle of techron with about 13 gallons of chevron, (I only use chevron or mobile gas) I purchased a fuel filter (wix brand made in USA) and will have that installed next week.
I had my battery checked and it was just on the verge of needing to be replaced so I purchased a new interstate battery and had the charging system checked, The tech said the alternator is working fine.
I am hoping the fuel filter cures the rough idle but could be a myriad of other things.
I still need to purchase a fuel gauge and check the pressure.....

 

Well this past week my van started hesitating when it was cold. After it warmed up it seemed fine but then seemed to have less power in drive on uphills. Say going 35 or 40mph and giving it the gas to speed up, it just didn't feel right. Another thing I noticed is running along say at 50 or 55 and let off the gas intentionally and immediately pressing the gas again, it feels like a slight delay to catch back up.

This van has always had a slight surge when sitting on a slight upgrade and giving it just enough gas to get it rolling. You could hear it more then feel it.

So I went a head and changed the O2 sensor even though there was no cel light.
I also had my muffler shop to cut the cats off so we could visually inspect them and they were fine.

I have only driven about 15 miles since the o2 change and the engine was warmed up so I don't know if I will still have the hesitation when the engine is cold or not.

What did improve is the rough idle and the surging starting off slowly on a up hill grade, it seems to be gone right now and the idle appears to be a bit smoother
I have a test track I use.... 4 or 5 miles up to the next exit from my house on the interstate and the same on the way back. It includes a 3 mile uphill grade with a a truck lane. Normally light traffic so you can run as fast or slow as you need to go.

This time I was able to hold my speed at 75mph up the hill with the truck lane without having to kick it out of OD but the peddle was at the point to where just a little more and it would have down shifted.

Ill try it again tomorrow when the engine is cold.

One more thing is that my tail pipe has always been black. After the run today it may just be me but it appears to be getting a little tan color to it. That may be too soon to really tell.

 

I forgot to mention there is a distinct fluttering noise coming from the air intake. The filters are not that old. I wonder if that sound is the Idle air control valve failing? I replaced it about 3 years ago.

Anna, mine is the opposite, It runs really good when cold but when it gets hot thats when it feels like it strggles to start sometimes and idles rough.

 

I know the term open and closed loop and that open is when the engine is cold and closed is after the engine is up to temp. I understand the very basics of this so I have started reading about it to try to learn what happens and what parts control each mode.

So the problem you are having is when the system is in closed loop. I haven't found any really god articles or videos pertaining to ford but here is a basic article to get started with understanding each one. I need to learn what, when, and why each part is used and in which mode.

After reading this article I began thinking about your van and wondering if it could be popping in and out of limp mode? If so then which parts need to be checked?

ECM MODES OF OPERATION
ECM MODES OF OPERATION

 

Not sure but It seems to run fine cold or warm, but when it is very hot it idles rough just like it did when the old Ignition Control Module was faulty.