Horrible mpg 6.5 TD!!! help please

[foxdenfarms]

My air intake is an aftermarket cone filter and with the wastegate will turn average 8psi accelerating empty. The drivers side front wheel I can get a half turn if I push it good but the passenger I struggle to turn it at all. I would record a video but I have it in the air until I put pads on it

 

[tanman_2006]

That front right sounds like an issue but it's not your overall problem. Sometimes a lot of little things can add up though.

Sent from: Source Unknown

 

[foxdenfarms]

Yeah i figured it was a problem im hoping since it needs pads bad it may solve the problem but i just need to figure out what else could be adding into this equation of horrible mileage, if i wanted bad mileage i would have stuck with my 500hp bbc dually.

That front right sounds like an issue but it's not your overall problem. Sometimes a lot of little things can add up though.

Sent from: Source Unknown

 

[tanman_2006]

I'd still be double checking for fuel leaks, the only time my mpg was that low was when my lines through the valley were leaking. They didnt leave puddles on the ground either, I think it was running off on the manifolds.

 

[foxdenfarms]

How would i check to see if it was leaking there? Because when i did the POT mod and wastegate and boost gauge it all seemed dry on top

I'd still be double checking for fuel leaks, the only time my mpg was that low was when my lines through the valley were leaking. They didnt leave puddles on the ground either, I think it was running off on the manifolds.

 

[Will L.]

I say focus on the tranny. When you are searching for an undetermined problem, always look at anything that is obviously not right. The tranny or torque converter is consuming all your power. If you had the bbc in it right now and the tranny was acting like that you wouldn't start replacing ignition components or playing with fuel supply right?

I agree verify there is no fuel leak, then move on to the tranny.

Unless your truck turned into a h1 then that fuel economy is ok!:shiiiiiite:

 

[Burning oil]

Well its hard to follow as there are two problems, bogging and poor MPGs
Before I understood you had to rev it then drop it in gear I was thinking bogging under a load/driving. Now it does sound like trans issue.
You need to fix the bogging before you can the MPG issue.
I would pull the pan and see if anything obvious is wrong. If a wire is shorting to the TCC it could be ingaged at wrong time (wierd it only does it cold) deffinately a strange problem.

 

[Will L.]

Cold tranny fluid is likely. Try plugging in block heater to have warm engine and cold tranny and see if that changes anything.

 

[WarWagon]

You have a SES light on with the engine running? Use the paperclip method to read out codes. Also trans codes WILL NOT turn on the SES light as the light is for emissions failures only.

The trick with a diesel engine is they return a lot of fuel to the tank. So good fuel pressure at idle can drop to a filter collapsing and diesel boiling vacuum at high RPM from the IP transfer pump. So you need to read the fuel pressure at idle and then snap and keep the throttle WOT to get a reading and see if the pressure drops to 0 or pulls a vacuum. Gauges that do not read a vacuum you don't know if 0 is zero or a full vacuum. Restricted tank socks have a bypass valve that looses high RPM engine power as they can't flow enough fuel through the bypass.

Any air leaks into the fuel system will cause all kinds of stalling, low power, and hard starting.

The Bog when shifting sounds like a lack of power for whatever reason.

 

[WarWagon]

My air intake is an aftermarket cone filter and with the wastegate will turn average 8psi accelerating empty. The drivers side front wheel I can get a half turn if I push it good but the passenger I struggle to turn it at all. I would record a video but I have it in the air until I put pads on it

Calipers like to hang up - I suggest you get rebuilt calipers for the brake job. Also look at the wheel bearings or hub assy. Take the caliper off and see if it turns free. If it does you should replace the rotors as well as they would be cooked from overheating. 3000 miles later as the fix you would get a pedal pulse from the hot spots caused by past dragging brake pads.

If the wheel is still hard to turn your wheel bearings are dragging.

 

[foxdenfarms]

Ok well I spent all day working on this truck, put pads on the front and had to pull the passenger caliper off and use a little elbow grease and a very big hammer but was able to get the frozen piston to release. Working great and free now remarkably as I figured it was junk. But it came out good, bled the front and still didn't have a pedal, was throwing the brake light in the dash on, was scared it needed a master as my dads 99 suburban had the exact same problem (hanging caliper) and we also had to put a new master on to eliminate the problem. But I decided to bleed the rears to see if air made its way back there and stumbled upon a pin hole in my brake line leading to the split in front on the rear end, well having to drop the half full tank to get to the fitting because it was a napa line so I do not know if factory fitting for the 3ft line was right beside the tank, dropped the tank replaced the line bled the rear and rebled the front hours later she is stopping as good as new. Whewww...now that that problem is taken care of I know the hanging caliper was not the whole reason for bad mpg, so tranny? Full of fluid but i have not pulled the pan off and gotten into it. I will when I have a free chance.

 

[tanman_2006]

While that tank was down you should have replaced/removed the tank sock.

 

[foxdenfarms]

Thought about it but was so frustrated with the brakes I just wanted it done but my truck has a flatbed so accessing the pump isn't hard