How do you know when your injectors are getting bad. I have 135,000 on a late 99 and my fuel mileage has dropped considerably (10mpg), doesn't have the power it had when I bought it, and blows a lot of black smoke when I put the pedal down. I'm just trying to figure out what it might be. I have a Superchips programmer, K&N filter, and 4" exhaust. Thank you

 

if your blowing black smoke that means you are short on air. First check your airfilter and make sure its clean. Second pull the boot of the intake of the turbo, then check for shaft play and also chekc the blades for wear. If i remember correctly side to side and up/down play is ok if minimal, but any in and out is bad. Sorry cant remember the exact tolerances.


luke

 

Exactly. Find and repair the air supply problem and you'll have your truck back.

 

I forgot to add, check all your intercooler boots and boots connecting the turbo y pipe to the intakes on engine.

 

It's that time of the year for winter blend fuel. I lost 2 mpg on the last tank. If mileage stays down and is consistent I would blame the fuel, especially if there are no performance issues.

 

Thanks for the help. It definately is not the winter diesel as it has been going on for several months. I also just cleaned my K&N filter, but that didn't seem to help. I will investigate the lack of air further. Thank you!

 

check all the rubber boots, between the turbo outlet and the intake manifolds. i could only get 11 psi before the wicked wheel. now i can activate my boost relief at 22 psi. my orange boots to the intake manifolds were really loose!, leaking alot of boost.

 

Okay, checked all the rubber boots and all seem tight. One thing I did notice is that there seems to be a lot of play in the pipes to the intercooler, maybe just my imagination. Checked out the fan in turbo, didn't notice any play and fins looked good. Anybody have any other ideas?? Isn't there a mod for the airfilter (6337)? I did a search and couldn't find anything. Thanks

 

do a search on" kwik flter" or kwik will chime inand give you a pic. and yes it's an easy modand worth it.J

 

You already have an air filter don't need the 6637 mod, unless it's a drop in. How hard are you on the pedal? I don't think thats your problem but I know how hard it is to stay off of it with the programmer. It might be injectors but I have 193,000 and no problems.

 

You are correct HP junkie, I do have an air filter, a K&N drop in OEM replacement. Most posts I have seen on the K&N is that they are worthless. But something is happening, and based off the advice of several other users it seems like a viable option. One thing to remember about a programmer is it dumps more fuel in, which requires more air to burn. At this point I am willing to try to anything to get my truck back to what it was. It just doesn't have the guts it used to, and the mileage sucks! Not much point to having a diesel, other than paying way to much for fuel, if the performance and mileage is worse than a gas burner. Thanks for the help though. Any other ideas what it could be?

 

Here's the link to the 6637 air filter thread.
https://www.ford-trucks.com/forums/s...d.php?t=277571

 

Thanks Kwikkordead. But don't you worry about water getting in without enclosure?? I do occasionally get into some pretty wet areas in the Upper Peninsula of Michigan during deer season. Any chance of damge?

 

I live in Seattle, rain capitol of the NW. Filter never gets wet.