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Discussion Starter #1
My E4od instantly goes into 4th after it shifts to 3rd without letting 3rd build up rpms.

Say if im going say 40-45mph,the tach will be at 1-1200rpm:scratchhe

Common problem with these trucks?

Codes: 334,173
 

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Satyr of the Midwest
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What about the speedometer? Is it reading correctly?
 

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Discussion Starter #4
BTW, It just went under a fresh fluid and filter change. But the problem was there before that.
 

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Satyr of the Midwest
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I'd verify that the throttle position sensor is signalling correctly. In other words, make certain the voltage signal increases linearly with throttle angle. Follow this diagram to see what I mean (click thumbnail):



Another factor is driving style. Our trucks typically shift into 4th gear between 35 and 40 mph, and the RATE at which you let off the accelerator does augment shift and TCC lock-up/unlock points.
 

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yo,
Great advice by SigEP!

Also, I replied to same or similar Q at another bronco MB; prob was you, Beast... Here it is w/exception of Hot Links..see that site for them;
I assume that fluid level and condition is ok, so; let's fix those DTCs first.

Was engine at normal op temp when you did da KOER portion of the test?
because; DTC 41, 42, 91, 92, 136, 137,139, 144, 171, 172, 175, 176, 177 & some Possible Causes for Rich & Lean HEGO The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature
Source: by Ryan M (Fireguy50) at fordfuelinjection.com

Next up in da batting order today is;
Torque Converter Operation Test :

This test verifies that the torque converter clutch control system and the torque converter are operating correctly.
1. Carry out Quick Test with scan tool. For additional information, refer to the Powertrain Control/Emissions Diagnosis manual (PCED). Check for DTCs.
2. Connect a tachometer to the engine.
3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in (D) position.
4. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph) and tap brake pedal with the left foot. 5. Engine rpm should increase when brake pedal is tapped, and decrease about five seconds after pedal is released. If this does not occur, see torque converter operation concerns. For additional information, refer to "Diagnosis by Symptom" in this section.
6. If the vehicle stalls in (D) or manual 2 at idle with vehicle at a stop, move the transmission range selector lever to manual 1 position. If the vehicle stalls, see torque converter operation concerns. For additional information, refer to �Diagnosis by Symptom� in this section. If the vehicle does not stall in (D), refer to "Diagnosis by Symptom" in this section.
7. If the vehicle exhibits a vibration during the road test complete the Road Test Evaluation Form. This form will aid the technician in determining the source of the vibration.

Note: The following is a list of common vehicle concerns that have been misdiagnosed as torque converter clutch shudder. For diagnosis of the following items, refer to the appropriate sections of the workshop manual and the Powertrain Control/Emissions Diagnosis manual (PCED).
> Spark plugs - check for cracks, high resistance or broken insulators.
> Plug wires.
> Fuel injector - filter may be plugged.
> Fuel contamination - engine runs poorly.
> EGR valve - valve may let in too much exhaust gas and cause engine to run lean.
> Vacuum leak - engine will not get correct air/fuel mixture.
> MAP/MAF sensor - improper air/fuel mixture.
> HO2S sensor - too rich/lean air/fuel mixture.
> Fuel pressure - may be too low.
> Engine mounts -loose/damaged mounts can cause vibration concerns.
> Axle joints - check for vibration.

by Ford via Steve83 @ http://www.supermoto...ry/media/202695
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A bad 02 sensor will show several symptoms:

Rich or Lean fuel condition
O2 sensor fault codes 136, 137, 139, 144 and 171 through 178
Reduced HP
..
Also, a quirky TPS could cause this with no DTCs;
Test & Operational Description & Parameters by Ryan M (Fireguy50) at http://fordfuelinjec.../index.php?p=30

TPS Response Graph; "...This voltage is measured with the TPS connected normally, the key in RUN, the black meter probe on the SIG RTN wire (Bk/Wh or Gy/R), & the red probe on the TP (DG/LG or Gy/Wh) wire. BEFORE attempting to adjust the TPS idle voltage, confirm that the throttle stop screw has not been tampered with..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at http://www.supermoto...ry/media/173616

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DTC 173
The engine is always running rich. Can be caused by a faulty Right or Rear (Bank #1) O2 sensor, cold engine, MAP hose off, or fuel system

To check the sensors first disconnect and inspect the wiring, remove the sensors and a DIY last ditch $ Saving Cleaning tip; clean them, don't use any type of chemicals to do this, the cleaning should be done by using a PROPANE TORCH, place the sensor tip inside the propane flame for a few seconds at a time until all contaminants get evaporated by the heat. Place the sensors back in place.

Regardless of how the engine is mounted in the vehicle, conventional or transverse, the HO2S naming convention stays the same in relationship to engine banks 1 and 2. Bank 1 (PASSENGER SIDE for 5.0/5.8) will always be the bank containing the #1 cylinder.

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DTC 334 EGR (EVP) closed valve voltage higher than expected; "...as rla2005 wrote; Make sure your EGR valve is closing all the way. Carbon can build up preventing it from closing.
The EGR may not be sticking, but it can be unseated enough that the measured value is too high. I had a piece of aluminum casting get stuck in a EGR valve once. It threw the same code, same can happen if there is carbon build up. The closed position EVP signal should be below .67 volts. The EVP sensor itself could also be bad. Checking and cleaning the EGR valve is cheaper than replacing parts, I would start there

Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary.
Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. If it leaks, there is carbon stuck on the pintle valve seat
The EGR Valve Position (EVP) Sensor used exclusively by Ford, can be the cause of driveability problems without ever setting any trouble codes. The relationship between the EVP sensor and the EGR valve is important to understand. Either one being out of spec can cause similar symptoms. Understanding this relationship will help you to diagnose uncoded driveability problems like stumbles, hesitations, rough idles and stalling.
Read through this for now by TOMCO; http://www.tomco-inc..._Tips/ttt34.pdf

it is for 34 but is sim. to 334... you'll need a hand op. vac. pump and DVOM; also some long thin straight pins to backprobe harness connectors.
Ck for Vacuum Leaks "....The PFE hose should be examined carefully. We have seen them with pinhole leaks. This causes the exhaust pressure to bleed off giving an inaccurate reading to the PFE sensor. They can also deteriorate because of the corrosive exhaust gases they carry. This weakens the rubber and may cause porosity or cracks. A quick check is to hook a vacuum pump to one side and plug the other side to see if it can hold vacuum..."

More EVP testing by Fireguy50) at fordfuelinjection.com http://fordfuelinjec.../index.php?p=35

My ISP stinks today; Comcast is really messing up here again so I can't open some of these Links now; some may be repetitive
EVR Overview & Test
Source: by Ryan M (Fireguy50) at fordfuelinjection.com

EVP Operation & Testing, Ford
Source: by Ryan M (Fireguy50) at fordfuelinjection.com He used Voltage measurements in da test;

TOMCO uses R in test; such as "...While watching the ohmmeter, gradually and steadily apply vacuum to the EGR valve (not exceeding 10 PSI). The ohmmeter should show a steady decrease in the OHM reading. If the ohmmeter needle has any sharp movements or shows a slight increase while applying the vacuum, the sensor is bad. There is also a range that the OHM readings should fall between. In some cases this ranges from no higher than 5,500 OHMs, to no less than 100 OHMs. Check with your service manual for the exact specifications for your vehicle..."
http://www.tomco-inc..._Tips/ttt19.pdf
 

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Satyr of the Midwest
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If the EGR valve isn't closing all the way, then you'll be opening the throttle farther than otherwise required for normal acceleration (or even for cruising). A similar condition can exist due to the oxygen sensor always reading rich; the PCM has reached the pre-programmed limit as to how lean it can run the engine. The combination of codes points to a stuck-open EGR valve, though.
 

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Discussion Starter #9
What part of the egr would need to be cleaned? the bottom? its only ~2yr old(so is the evp sensor) so I dont think carbon should be that bad.

On the other hand the truck seems to idle better with the evp unplugged.?
 

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I had this same problem. Mine was the TPS. The truck now idles prefect and shifts perfect.
 

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Discussion Starter #12
bump. Still have this problem. Is there anything electrical inside the trans that would make it skip a gear?
 

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Discussion Starter #13
What part of the egr would need to be cleaned? the bottom? its only ~2yr old(so is the evp sensor) so I dont think carbon should be that bad.

On the other hand the truck seems to idle better with the evp unplugged.?
bump. Still have this problem. Is there anything electrical inside the trans that would make it skip a gear?
Bump,still have this problem.
 
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