poor fuel mileage
 

I started tinkering under the hood and pulled my air filter. The filter looked okay but I replaced it anyway. When I removed the air filter I found a rats nest between the air intake and the filter in the oem filter box.

This week we took a 400 mile trip towing my 16 foot Featherlight GN horse trailer. Going I drove mostly freeway 55-60 mph empty. Returning home loaded [one shetland pony for my 5 yo grand daughter] I had some long grades to pull, but maintained 55-65 mph. I averaged 15.5 mpg.

I have 190K on my injectors and am wondering if they need some attention or replacement. I am reluctant to go to a garage as I have not fully recovered from the last rapeing I got. I am sure that I could exchange the injectors myself but attempting the job the first time without some experienced guideance is a little challengeing. I would hate doing the job less than perfect.

Also are there any proven Super Chips that would provide more power/economy that are easy to install and are not so expensive? All my friends on Diesel Bombers have been very helpful to me and I appreciate all your input and advise. I wish I was not so damn old, I think I could have had a lot more fun enjoying the things you folks do. Thank you, Kerley

"Fuel pressure at Idle is 25 pounds and at wot 19 to 21 pounds".
I been told that 25 at idle is too high, it should be arround 18-19.
25 psi at idle will kill ur vp.

I've heard both ways on that as well. I have 24/25 at idle, and never go under 21 under WOT. Every time I run into someone that works at a diesel shop I ask them about fuel pressure. They mostly say its fine, and a few say 25 is at the limits. I figure if it works, great! Don't piss with it unless it needs it.

ench35
 

The air intake is around the right head light and there is a large opening under the passenger side battery then up through the fender to the air filter. If you had a rats nest in the air cleaner box there is a good chance there is some more material in the fender. you might try back flushing the fender well with a water hose. I washed a shop towel out of mine when I flushed mine and needless to say I am getting better mileage. PS>Red Dog recommends 18 PSI max on the lift pump for the 1998 24 valve at idle you might try that also.

Thank you all for the honest input. What I finally did was check my Intercooler boots, they looked okay from the top but when I got under and looked at them two were torn. I ordered a set from one of the DB suppliers and I installed them, also I removed the factory air box and ordered a new Donaldson BHAF 42790 and heat shield from another DB supplier. I have to tell you SHE BOOGIES now. I have plenty of power and am very happy with my Cummins. She runs and pulls so much better that I forgot all about the mileage.