turbo lag

[bighornby]

anyone have any suggestions as to why i have turbo lag and how to eliminate it in my 2005 ford f250 td. i have just bought a s&b cold air induction system and elbow. i was told this would help along with a bigger exhaust which is on my shopping list. my truck jerks and hesitates when i accelerate which i assume is turbo lag. any input would be appreciated.

 

[lwmcguir]

None of our 6.0 engines ever did that and we never had any turbo issues. We did have some injectors fail and prior to the complete failure there was some hesitation. The diagnostic computer is pretty good for the 6.0 series so you should have a message if somthing is wrong. Do you have all the latest flashes on the engine computer? I would take it in and have the EGC and Oil Coolers checked. You might have a nearly plugged EGC.

Good luck with it. Let us know what you come up with.

 

[caissiel]

The possible cause of the turbo lag could be the EGR valve that will stick open.
When the truck requires lots of power the valve shuts off to allow more turbo pressure and cleaned air to the engine intake.
It has nothing to do with the intake and exhaust system.

One way to check it is to disconnect the EGR valve and drive the truck that way, if its bad it will not open and stick open because it is not plugged in. If the valve is dirty it might also be stuck open and needs to be removed and cleaned.

An other possibility is that your turbo variable vanes are sticking and will not move when required. This will happen if the truck is idled a lot at low RPM. with the EGR valve open and introducing dirty air in the turbo exhaust inlet.

In addition people have had injection control box (FICM) failures that will cause this.

If you unplug your EGR valve you might get the light but mine has never cause it to light when I did it.

I do have the EGR delete kit and its been great satisfaction and assurance.

 

[pmmjarrett]

You don't have a turbo lag issue. You most likely have a fuel or emmissions issue. The 6 Oh No is known for a lot of problems but they do deliver smooth power with very very little lag with the variable vane turbo.

Change fuel filter if you havn't is the first place I'd look. Then check EGR. If the vanes on the turbo were stuck this could cause lag, that is about the only issue with these turbos other than the early ones made a lot of whistle that people didn't like.

Even with older engines that had noticable lag, it shouldn't be jerky.

 

[ricatic]

Some good advice so far. I suspect fuel issues. The 6.0 is very sensitive to fuel pressure. Always use OEM fuel filters on the truck. also use only OEM oil filters. I would recommend cleaning the EGR valve. Unplug it, remove the 2 hold down screws and wiggle it loose. It can be stubborn but it will come out. The truth about your new elbow; no help there. The only performance gains there are at the sellers bank account. The stock intake system on the 6.0 has been independently tested against all the major intake aftermarket systems. It has been proven that until you reach 3700 rpm, no increase in air flow. The OEM Donaldson filter also filtered measurably better than any of the aftermarket stuff. A full 4 inch turbo back exhaust system is a great modification that lowers EGT's and increases turbo response. Here is a long writeup I prepared a while back on the 6.0. By the way, I have never seen a Ford 6.oh no...

//heartlandowners.org/showt...gine-long-post

Regards

 

[hoefler]

You don't have a turbo lag issue. By looking at your signature, I see you have a power box on your truck. I would look at your injectors, most likely you either have a cracked one or two or just worn them out.

 

[caissiel]

I would bet its EGR related. These Ford usualy are solid other then the EGR system.