I am having more than my share of frustrations with this truck. I just can not nail down the problem. It has been to the Dealership 3 times to get it checked out and every time they say nothing is wrong.

I have a VERY rough idle. Feels like a misfire, but I am left scratching by head. PLEASE HELP. This engine was massively overheated and driven till it died. The upper radiator hose came off the thermostat housing and dumped the coolant. It was dark and rainy so I could not see it and the temp gauge did not rise due to the fact the coolant was gone. The head gaskets were replaced and the heads repaired at a machine shop, all under warranty by the Ford dealer.

Here is the data and work done so far:

2003 Ford Ranger Edge 3.0l V6 FFV 2WD with 5 speed 5R44E Automatic Transmission.
**62500 Miles on the vehicle

NO CKECK ENGINE LIGHT

1. Recent compression check numbers:

cyl1 161
cyl2 156
cyl3 160
cyl4 160
cyl5 146
cyl6 165

2. Vacuum check:

18.5" and steady

3. Fuel Pressure check:

a. ~40psi with key on engine off
b. 60psi with engine running (Needle on gauge does vibrate)
c. Leak down test:
- Fuel psi drops from 60 to 50 when engine is shut off and holds steady
- Pressure drops ~12 psi in 30 minutes<O
<O</O

I have changed or had the dealer change the following:

1. Coil Pack
2. Plug wires = Autolite premium
3. Plugs = Autolite Extreme Performance XP104 gapped to .045"
4. Upper Intake Gaskets
5. Heads and Head Gaskets due to an overheated engine.
6. TPS (throttle position sensor)
7. IAC (idle air control) valve
8. Fuel Filter
<O9. Camshaft Position Synchro and Sensor

I have performed the following recent maintenance:

1. Oil and filter = Valvoline Maxlife 5W-30 w/ Motorcraft filter
2. Seafoam through the brake booster hose twice in the last month
3. 3 tanks of Shell 87 with Techron or Gumout w/ Regain fuel system cleaner
4. Winn’s fuel system service = same as seafoaming in reality
5. Cleaned MAF with CRC MAF cleaner
6. Quick smoke check through the Brake Booster revealed no obvious vacuum leaks.<O</O
7. Sent oil sample from last oil change to Blackstone for analysis. Blackstone report found nothing.


I have checked the PIDs with my scanner. Specifically checked the following:


ALL CHECKED WITH THE ENGINE AT OPERATING TEMP WHILE IDLING

MIL STATUS OFF
ABSLT TPS % 18.0
ENG SPEED RPM 808
CALC LOAD % 16.4
MAF FLOW GR/SE 4.98
COOLANT �F 190
IAT �F 96
IGN ADVANCE DE 18.0
ST FTRM1 % 1.5
LT FTRM1 % -4.6
ST FTRM2 % -1.0
LT FTRM2 % -5.1
VEH SPEED MPH 0
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
O2S11 V 0.095
ST FTRM11 % 3.1
O2S12 V 0.765
O2S21 V 0.695
ST FTRM21 % -3.4
MIL DIST mi 0
OBD2 STAT CA

 

Anyone?????

 

Your 'header' is not attracting attention, obviously...

That said, if this engine got hot enough to die, it got hot enough to score the cylinder walls, and ruin the crankshaft. I am surprised that you only had the heads worked on and got as far as you did. The compression numbers look good, with only #5 down a bit.[and #2 -directly opposite each other.] There should be enough compression to run decent, in my opinion.
I would check for intake leaks using WD-40 or propane or your chemical of choice. Spritz or flow gas around the gaskets while idling. Heck, feed a bit into the air cleaner through the crankcase breather duct, and see if the idle smooths out. The idea being to test for a lean mixture. If you look at your numbers for the O2 sensors, they are all showing a 'lean' condition. They produce voltage that DEcreases the more O2 that is available in the exhaust. Low==lean is my memory helper. The voltage MAX is ~1 volt. Yours are near zero, well, loooow, anyway. It is possible that you poisoned the O2 sensors with anti-freeze as it was apparently going everywhere unbeknownst to you.
So, check for leak, check for lean by adding some extra fuel, and test your O2's would be my first looks.
tom

 

Well we can add 2 new upstream O2 sensors and a new MAF sensor to the list of things done. Still no change. When I got it back from the Dealer last week, there was no mention of a lean condition. I was told that there was nothing wrong.

I checked for vacuum leaks again none were found. A mechanic put it on a smoke machine and found nothing.

Other than the Idle, it seems to run great.

I am just having a real hard time convincing myself that this engine has a characteristic idle like this.

 

I looked at the O2 numbers again, and realized that I had apparently seen what wasn't there. The first sensor reading listed was low, in my viewpoint, but the latter two seemed to be ok, and actually a little high.
Are you getting a hummmmmmmm putt hmmmmmm mmmm mmmmm putt out of the exhaust? Where the exhaust sounds regular, with irregular 'putts' mixed in? Or is it a shaking of the engine on the mounts?
I have heard of the 4.2 engines having coolant leaks that cause hydro lock, and subsequent bent connecting rods. The symptom noticed later on is an irregular idle that cannot be 'tuned' out by any corrective measure.
If you have the time, you could measure the stroke on #4 and #5 to see if they are different, fwiw.
Need more description of what's happening.
tom

 

Here in a clip of the exhaust I took today. It sounds normal to me. Sorry about the audio quality, but this is the only video camera I have.


PICT0001.flv video by lorenambrose - Photobucket


I have been tracking the coolant level for two months and the truck does NOT loose a drop and the temps are rock steady.

 

Also I have been tracking the coolant level for two months and the truck does NOT loose a drop, and the temps are rock steady.

 

Is the crankcase overfilled? You could try a set of Motorcraft plugs, Autolite isn't the best brand IMO.

 

overfilled??? I am not sure what you mean. If you mean oil, it takes 5 qts with the filter to top it off completely.

As for the plugs, it runs exactly the same on brand new motorcraft plugs. I do not think plugs are the issue.

Agressive fuel system cleaning seems to make a noticable difference. I wonder if this is one of the notorious ford carbon miking engines...

 

I am not a guru, but one of the O2 readings was near .1v(.095) O2S11 the other, O2S12 nearer to .8 if you round off. The MAX they will produce is ~.9, indicating a rich condition. They should be closer to each other in their readings. I *think* that the last (O2S21) sensor is the one after the catalytic converter, checking converter efficiency.
Take a minute to consider what causes the engine to run: fuel, air, spark. The compression numbers are real good, the plugs are new, the wires are new, the only thing that isn't new are the injectors. You have a leakdown to ~12psi after time, so could have an injector that doesn't work properly. Could be intermittently failing, or leaking when it shouldn't. The heads just being done, they should flow air and do have good compression. Can you do a 'cylinder contribution test' on this engine? The computer on older SEFI vehicles could check each cylinder and note any which didn't measure up to the others.
I'm thinking a sticky or leaking injector, but won't bet my paycheck on it.
tom

 

Well I have been having trouble with this truck for awhile now. I went out today and did some real troubleshooting and thinking and think it may be a bad valve.

Here is what I have now:

1. Engine runs rough at idle, but ok at highway speeds.
2. After a 15 minute warmup at idle the forward O2 sensor on bank #2 steadily climbs to about .775v and does not fluctuate, indicating a steady RICH condition.
3. During the same time the #2 bank long and short term fuel trims go steadily lean.
4. If you hold an index card over the exhaust pipe it will get sucked down to the pipe intermittently.
5. Cyl 5, which is on bank #2 has slightly lower compression than the rest of the cylinders.
6. Engine idle drifts up and down through a range of about 50 RPM's.


To me this is screaming "BAD VALVE".

What do you guys think????? Could it be anything else?

 

If you are feeling adventurous, you could take off the rocker arm cover, and loosen the rocker arm nuts 1/2 turn or so. If the valve job was done and the seats ground, it is possible that there is just a little less clearance in the train. The tip of the valve stem could be raised up just a bit from where it should be, barely in tolerance, and causing the valve to not seat properly.
Loosening the nuts will allow the rocker arm to move up a bit, allowing the valve to close a bit if it were held open. You can loosen them one at a time, until they tap, and then tighten them to 'quiet' for testing purposes.
What do you have to lose????
tom