Greetings !
Newbe here. Requesting some thoughts.

Specs: 2007 F250 PSD, 52k miles, no-mods.

Symptoms: Start cold just fine. Starts warm just fine. However, if shut off about 5-10 minutes after a cold start (I'm talking summertime cold start), the truck will either not start at all (cranks fine), or, starts but runs like fuel is bad, or, something seriously wrong.

More symptopms: If it starts at all during this mid-warm-up time, there is NO throttle response - I mean none. Put the pedal to the floor and no change to idle. And when I say idle, I mean barley running, with a sound that is barley audible - nothing like a normal diesel sounds.

This has been happening over several tanks of fuel, and again, ONLY if I shut it off during the warm-up period. I leave my house in the morning for work, drive to the local convenience store for coffee, and when I come out I encounter the problems. If I keep driving i.e. no coffee... all is fine.

My initial thought was some sort of temperature sensor malfunction, but there are no codes stored in the ECM, and no check engine light on. I would think a problem like this would trigger a check engine light. Secondary thought was Throttle Position Sensor. More often over the last month or two, in this warn-up period, if driving, the throttle seems sluggish. There is a noticeable lag in spool-up of the engine, then it takes off. Other than this warm up period, the truck runs excellent. Plenty of power, and starts (and runs) just fine after warm up.

One other symptom, that may or may not be unrelated. Two or three times over the last year, I start it up in the morning and the check-engine light comes on, and the fuel gauge is pegged to empty (regardless of the fuel level). Code reads fuel level malfunction (not sure of the exact code number). The situation rights itself shortly after a few minutes of driving. I clear the code and it may not happen for another couple of months. The no-start issue is more recent, and is not associated (timing wise) with the onset of the no-start situation described above.

Any thoughts? Anyone else run into this problem? Any thoughts would be appreciated.

Thanks...

Larry

 

The first thing you need is something to read live data. Scan gage or torque pro are the most common. Torque pro in an app for an android smart phone. there are similar for iphones. the Bluetooth adaptors are about $20.00 on line, the app is about $5.00. Where are you located? maybe someone local can help you out

 

Need ICP, IPR% and FICM main volts during the non-start crank.

FICM Synch and Cam/Crank synch would help.

Josh

 

It could be a lot of things but next time it acts up, try unplugging the EBP sensor (Exhaust Back Pressure). It's on the end of a metal tube coming out of the driver side exhaust manifold.

You'll get a cel but if throttle response returns and it runs ok you'll have your culprit.

 

Thanks for the reply. I do have the Torque app for my Android phone, but I don't think its the "Pro" version, at least it doesn't say so. Anyway, it usually gives me some kind of error when starting, indicating my vehicle is not compliant with ODBC. Weird, but it will still read codes, and has the ability to clear codes. Although I have never seen where it reads voltages on sensors, but then again I don't have much experience with it.

 

You do have to load the 6.0 spacific peramitures . Should be able to find a u tube on it. try this one

 

Rusty... you're a genius ! Tonight was the first opportunity I had to try your suggestion... and it worked ! I had parked it after arriving home from work, and it sat for about 2-2.5 hours and when I went to move it, it wouldn't start. Pulled the plug, and it started.

So... you say it's a Exhaust Back Pressure sensor... does that mean the sensor is bad, or it's sensing too much back pressure? I assume the sensor is bad because it runs good all the time, with the exception of the sluggish throttle during the mid-warm up period. Cold and the throttle response is good, and hot the throttle response is good. Just in that mid warm up range it take an extra second to spool up and take off.

Again... Thanks for the tip !

 

Glad it worked for you, I'm sure I learned to check this here on FTE . Inspect the harness and plug for the sensor carefully, if it has any issues a replacement pig tail is available, if that's ok, a new sensor should fix it. Yup, it's an Exhaust Back Pressure Sensor (EBP).

Be sure to use a second wrench to hold the tube when pulling the sensor and run a piece of wire or weed wacker line or something down the tube to make sure it's clear before reinstalling the new one.

 

FOLLOW-UP ==>
Well... I replaced the Exhaust Back Pressure, and reamed out the pipe. This was about 2-weeks ago. Yesterday... problem reappeared, with no change in symptoms.

Today, the only code stored in the ECU is [B1352]. However, I don't think my Torque App is working correctly, or, I'm using it wrong.
First, I get a warning message saying "ECU does not support reading any PID's". Then, when running a test, it returned "ECU does not support mode $06". I have no clue what those warning mean. Am I using the equipment incorrectly??? Torque version = 1.8.62, and ODB link is ODBLink, MultiProtocal ODB Scan Tool, Part Number: 408101, Hardware Revision 2.6, with a Mfg Date of 3/17/2011.

Back to the truck (2007 6.0 w/53k miles))... yesterday when it acted up it was the same circumstances as previous, in that it either will not start, or like yesterday, it started almost immediately, but idle was about 350-400 rpm's... and had no throttle response whatsoever. Pump it, floor it, hold it half way down - no change or response. I even held it on the floor for almost 30-40 seconds and nothing. Then, after 40 seconds or so of being held on the floor, it took off like a bullet. Rev's shot up like they should. After that, no problems at all. Driving, power, and throttle response pretty close to normal. (throttle response has been a little sluggish lately, but only a times, and more during the warm up period - warm, it seems ok)

If this thing has a throttle position sensor, AND, it is controlled, or at least influenced by coolant temperature (or ambient temp), then I'm thinking that would be the area to look at. But that's just a SWAG based on symptoms. I know next to nothing about diesel engines.

Anyone have any thoughts ???