Not a brilliant back yard mechanic here but shall we say rather enlightened in all things mechanical (enough to be dangerous).

'95 F-150 5.0 XLT 4X4 Auto trailer towing.

Almost 180K and I have had it since there was 16K on the ticker.

OEM internals with tweaks and massage of Intake, Exhaust, Ignition.

Since I first got the truck I have had to always restart it a couple of times because it dies the first start of the day.

When running correctly:

I have effectively taken mileage from 12/16 to 18/20 and still have room for improvement with a tweak of oxy sensor voltage output.

If I start with cleared codes the idle is dead smooth. Can't even feel it idle at a stop in drive or park. Throttle response, WOT horse power and torque are exceptional compared with stock. This status is constant through about 4 or 5 start / drive / shutdown cycles.

The "problem" arises (missing, bucking, low erratic idle) after this series of cycles, when the under hood temps are sufficient to heat soak everything when it is shut off and allowed to sit for 30 minutes or so. I think it is timing/detonation related.

If I crack the hood to allow air flow, it shortens the period after restart until it runs, idles and drives fine. If I leave the hood closed I need to (barely) drive a couple of miles until temps are lowered under the hood before it runs right.

Because of the higher miles I have been systematically replacing all emissions / ecm sensors, relays etc. (IAT, MAF, EGR Valve, Oxy, Temp sender, TFI, new distributor, new super duty fan clutch, water wetter, 14 lbs radiator cap, thermostat, 60/40 water to antifreeze.

Through all of this I have had no "Check Engine" light. It has come on momentarily maybe a dozen times in the last ten years.

Recent codes pulled engine off are 211, 212, 334, 639, 659.

Engine running codes are 536, 538, 632

After recent work, I need to pull them again.

Your thoughts ?

 

Code 211: Two or more successive erratic Profile Ignition Pickup (PIP) pulses occurred

Very common problem on these trucks. Classic failing PIP symptoms you listed.


Code 212: Loss of IDM input to EEC

I bet you put a gray colored Ignition Control Module (ICM) on the truck. It's the wrong one. Many part manuals are wrong. You need a black colored CCD-style ICM, not the gray Push-Start ignition ICM.


Code 334: EVP circuit above the closed limit of 0.67 volts.

EGR valve could be stuck partially open, it could be bad or the EGR Valve Position (EVP) sensor is bad.


I'll leave the transmission related codes to someone else.

 

Interestingly enough is that the original ICM module was gray! Granted it is 20 years old and manufacturing parameters can change. There was a noticeable difference with the new one and not performance related, the tach drops to zero when you hit about 2100 rpm. As soon as rpm drops below that, if registers.

More pieces / parts are coming from RockAuto. GOD I LOVE THAT PLACE !!!!

Question: Over the years has the EGR Valve position sensor proved to be relatively bulletproof or do people see failures requiring replacement? A tad bit expensive most places but I have found a reasonably priced source.

 

The EVP is preloaded by the EGR valve spring/diaphragm. It's chicken or the egg syndrome. Either one could be bad or both.

I pull the EGR off, clean it and inspect then reinstall. If the EVP output is still high I replace the sensor. Works most of the time. One time I found a piece of aluminum casting wedged in the valve. Very lucky it ended up there and not down the intake tract. This was on my first 1993 Lightning that had 52k on it. My luck ran out 3 years later when a 60 foot Hickory tree fell on it.

 

Before I changed my '87 to mass air and even after that all 3 of my trucks ('87, '89 & '94) start and stay running on the first try. Why is it shutting off? I'd start with that issue.

 

Damn man ! If it's not one thing, it's her mother !
Thanks !

 

So with an automatic the ICM/TFI is supposed to be Black right? So it is running on the gray unit I switched out for but the previously mentioned tach issue has now changed a bit as it will work up through 3k now before going to zero.

I am thinking the ECM, even with canceling codes, takes awhile to adjust to changes such as replacing out of spec sensors that get replaced etc.??

 

The transmission has nothing to do with the Ignition. 1994 and later trucks all have Computer Controlled Dwell (CCD) ignitions.

Clearing codes does not reset the stored data for each key sensor. When replacing a sensor it is highly recommended to cycle power to the computer to clear the Keep Alive Memory. Otherwise it can take some time and multiple drive cycles for the computer to adapt to the new sensor.

An Ignition Module is not one of those sensors. In fact the computer really has nothing to do with the tachometer at all, that is an analog function measured by the tachometer.

Some good reading here about the ignition systems Ford used in this era: http://www.myo-p.com/Ford-EEC/EEC%20..._or_black.html

 

good luck with figuring out your problem. I'll be watching this thread in case I or any friends run into this situation.

What did you have to do to your truck to get the mileage improvement?

Thanks,
Gary

 

Question: What state is the ECM in after powered down. My understanding is that the "limp in Mode" is an enrichment and I assume center of the road parameters otherwise. Is this the initial program after powering it down until the learning curve is completed? I have always understand that to be at least 10 miles of a steady state type of driving at speed?

The mileage gains have come about:

K&N Filter Charger / Shorty headers with 1 into 2 stainless Cat back system / a bit of a Frankenstein ignition system consisting of a later generation Jacob's Mileage Master ignition system and incorporating the coil trigger from an early generation Jacob's system because I like the redundancy of basically having two ignition systems to avoid being stranded. The OEM coil has been changed out for an Accel unit also.

The SixLiter tune with timing at 12.5* BTDC, a set of Motorcraft ASF32C copper cores side gapped to .052. They are a step colder to compensate for the intensity of the system spark. MSD 's Super Conductor wires and heat resistant boots.

6 ounces on average of pure acetone anytime I fill one of the tanks from empty.

To come is the installation of Eagle-Research Energy Solutions "Electronic Fuel Injection Enhancer" unit which effectively allows one to lean the combustion mixture in very fine increments by controlling the Oxy sensor voltage output. No, it's not snake oil, look it up.

 

It turns out there is no real rhyme or reason to the color of the assortment of aftermarket ICM/TFI out there so it must be assumed it applies to Motorcraft parts then?

Also, the longest running problem that I have had has now been resolved. As of right now it appears as the PIP has been my main culprit. Starts fine now, textbook 1500 rpm cold then settles to 700 rpm. After driving and heat sinking the underhood enviros, it motors on flawlessly now.

 

The issue really boils down to many Ford part catalogs for this vintage are wrong. Many aftermarket suppliers base their info on Ford's documentation so it has been perpetuated. It's easier for most folks to understand the correct "color" instead of the Push-Start versus CCD style ignition systems.

So in the aftermarket world color may not mean anything, MSD red for example, so you better pay attention to the product specifications.

 

The 211 code pretty much told you the root cause. Glad to see the 'puter was correct and you got the issue resolved.

 

So, I have an extra functional part in the bin, no biggy.

I plan on being buried in this truck anyways!

 

I have had to resurrect this thread as my issue has not been resolved.

I took my truck to an ASE shop owner with 25 years experience as my rough running and popping when the engine bay is heat soaked is still a regular occurrence. He pulled every possible code, engine off, engine running and driving it and found nothing. OBDI was apparently developed to put a handle on exhaust content and never as a true diagnostic tool.

My question now is: Is it possible that an old Throttle Position Sensor could give erroneous signals when soaked with heat verses when it is cold?

When the engine goes down on power and bucks, kicks and pops, the transmission wants to prematurely shift into higher gears. If I have erroneous voltage output, is it possible that mixture, timing and shift points could be effected???