And while I have your attention, is it common that when you get in the truck, and first start driving, and are going around 20-25 mph, that the rpm and engine and throttle hop up and down. Vhroom... Vhroom.. From like 2000 rpm to 3000 and back down???

This happens if I back out of my driveway and am driving slowly down the neighborhood street. And its only after I first get in it, and yes, I give it a min to warm up.

Does this indicate a problem or is it always going to do that? I actually feel the throttle in the truck hopping like that. I didnt think its normal, but it doesnt do it all the time, but enough for me to have to go faster than I care leaving the house to avoid it.

 

Do you wait any before engaging in drive? . . you might be selecting a gear too quickly before the electronic idle brings the truck back to operating idle.

 

Never experienced that in mine.

 

well mine has been in the shop for 2 full day now today will be the third, just waiting on a call that its done they said they were going to do both sides. How hard of a job is it? Do they have to remove the heads or anthing? whats it take to do?

 

I had the low speed surging you describe. I had my PCM reflashed and that fixed the problem.

 

Yes, I give the truck a min. I get in, turn it on, let it sit for a min, put it in reverse, back out, stop, put it in drive, then idle down and then apply some gas to get down the street slowly. It still hops a lot.

Im ging to bring this up about the PCM and also the noise to the other dealership here and see what happens. I foresee a lot of stress in the next few days.....

 

I just got mine back from the dealer for this problem. I have had it at the dealer two previous times for the same thing.. Each time, I take a mech with me and I can't duplicate the problem. Each time they check and report that no error codes have been registered. I am also running the most current PCM. All I know is I have the problem well documented in case I need to refer back to it in the future. The mech said by my explanation of the problem, it sounded like a "warm soak".....whatever that is. Doesn't matter if the engine is warm or cold.

 

After the dealership reflashed my PCM, they told me the next step would be to replace the throttle body if the reflash didn't fix it.

 

FORD: 2005 Mustang
2004-2005 F-150
2005 Expedition, F-250, F-350
LINCOLN: 2005 Navigator

This article supersedes TSB 05-15-8 to update the Service Procedure.

ISSUE:
Some vehicles equipped with a 4.6L 3-valve or 5.4L 3-valve engine may exhibit a ticking and/or knocking noise after reaching normal operating temperature. The noise may be described as "ticks", "taps", "knocks", or "thumps". In some cases the noise may be a normal characteristic of these engines. In other cases the noise may require further investigation. Sorting out and defining the noise as reported by the customer is important to successfully diagnose and/or repair the condition.

PRE-CHECKS

Diagnose noise when engine is at normal operating temperature (Oil at 160° F (71° C) or above). Verify oil temperature by using a diagnostic scan tool and monitoring the engine oil temperature (EOT) PID.
Check the type of oil filter installed on the vehicle. A dirty or clogged filter may cause a pressure drop. Look for aftermarket brands not recognized in the market or a production filter that has gone beyond the standard Ford recommended change interval.
Check for signs of oil brand used and viscosity (interview customer if needed). Motorcraft SAE 5W-20 Premium Synthetic Blend Motor Oil or equivalent is recommended.
Once the above pre-checks are complete, check for sound level from the following components, in the order listed. Compare the sound from these components to the noise the customer is concerned with, to determine the source of the noise.

VALVE TRAIN

Lash adjusters can make a ticking/tapping noise noticeable at any engine RPM/temperature and is audible through the wheel well or an open hood. However, with the hood down, lash adjuster noise can be heard as a light tapping noise through the wheel well and is considered normal.

Tracing this noise must be isolated to a cylinder bank. If one bank is louder than the other bank, focus the diagnostic to the loud bank. If both banks seem loud with the hood down, compare wheel well sound level to one another and work on the loudest bank.

Use a stethoscope on the top of the cam cover bolt heads to confirm which bank is affected. Move the probe from front to rear if necessary.

If isolated to a specific bank replace all the lifters, intake and exhaust, only on the affected cylinder bank. If the noise can not be isolated to a specific bank, then in the majority of situations this would not be a lifter related noise.

VARIABLE CAM TIMING

The 4.6L 3V and 5.4L 3V variable cam timing (VCT) feature may emit a light knock in normal operation and is audible only at idle speed, with a hot engine (gear selector in park/neutral). However, it may be masked by or mistaken for other noises generated from either injector firing or a malfunctioning valve train as described above. The noise does not affect performance or durability of the part.

VCT phasers may knock at hot idle. It may be heard inside the passenger compartment, or the wheel well area. Some light noise is normal. The engine may require a cold soak overnight for a full diagnosis to effectively be made at hot idle, particularly when a VCT phaser is suspected. The knock is not prevalent at cold temperature.

To test for VCT noise:

Place the transmission in park or neutral.
Bring engine oil temperature to 160° F (71° C) or above as indicated by the scan tool "EOT" PID.
Allow engine to idle, and determine if noise is noticeable.
Set engine speed to over 1200 RPM (if noise is a VCT knock, the noise should disappear).
Return engine speed to idle (verify knock returns).
If the noise intensity is more than a lightly audible knock at hot idle under 1200 RPM at engine operating temperature, replace the cam phaser using the camshaft "In-Vehicle Repair" procedure found in the Workshop Manual. If the noise is only a lighly audible knock at hot idle under 1200 RPM, do not attempt to repair this normal engine noise.

PART NUMBER PART NAME
5L1Z-6500-A Lash Adjuster (2005 Vehicles)
3L3Z-6500-BA Lash Adjuster (2004 Vehicles)
3R2Z-6A257-DA VCT Phaser and Bolt