Need help and some opinions please

Jeep4ever617 · **Posted:** Mon Jan 03, 2011 5:00 pm

Okay so first thing is I am getting some pretty unheard of MPGs is my CRD. I installed a new Thermostat in it about 2 weeks ago because mine was stuck open and running cool. I was anticpating a significant mileage increase with the new thermostat now that the temp is running much higher. Last tank of fuel before new stat was 14.9mpg. Last 2 tanks after new t-stat in order were 16.89mpg(mostly highway) and 15.19mpg(70% city driving). My MAP sensor is clean and new this year, air filter is clean, oil is good running Rotella T6 5w-40, fuel filter is not quite do for a change and there are no engine fault codes. I am not a gentle driver but I am not accelerating at WOT neither. I do have a Kennedy Lift pump in my possession which brings me to my next question.
I need some more info on fuel aspect of installing the lift pump. I have looked thru the link for Kennedy Lift pump Installation in the Tech section, but I need some more info on the proper way tieing into the the existion fuel line-which line is feed and return, also how and where were the line connections made(don't want to chance any leaks). My comfort level isn't high enough to attempt the install although I understand all the wiring.
Any and all opinions are welcome and appreciated:). I love my CRD but it is running me dry at the fuel pump:(

dgeist · **Posted:** Mon Jan 03, 2011 11:00 pm

That mileage is pretty low, unless you're just not ever really letting it warm up. A new t-stat won't help if it never runs long enough to get up to temp. Also, you're in Pittsburgh..I don't suppose that 70% city driving is on pittsburgh hills? Are you calculating by hand or with the EVIC and are you sure your numbers (odometer, etc) are correct? The numbers may be lying to you.

Dan

LibertyCRD · **Posted:** Mon Jan 03, 2011 11:19 pm

Sticky brake calipers? That's a known issue on these Jeeps.

Jeep4ever617 · **Posted:** Mon Jan 03, 2011 11:39 pm

No EVIC so it is hand calculated and I just had new rotors put on and the calipers checked out fine according to my mechanic. I usually let it warm up for 5-10 minutes when its cold but even throughout the hot summer I rarely broke 19mpg with mix city and highway. I am hoping that after I get the Kennedy lift pump and Suncoast TC installed here soon that I can get a good increase by getting the HOT flash done by GreenDiesel.

Joe Romas · **Posted:** Tue Jan 04, 2011 8:41 am

Actually I've gotten similiar figures in winter months in stock configuration :dizzy:

I don't know anything about your tires but they might be part of your problem. If most of your driving is below 65 mph get a tcm tune! Going back to the pre F37 tcm tune all US crd's left the factory with increased my 90% city driving 2 to 3 mpg's just by shifting at earlier speeds, about 5 mph sooner, keeping the engine rpm's low. Then consider GDE's full torque tune if your mainly looking for mileage. Then your jeep will be a tad better then the day it was new before it was casterated by F37 :cry:

But you'll need a better TC for sure.
My winter figures so far this year are 18-21 mpg's. Summer figures after tunes were 22-25 :lol:

Towing our 3000# travel trailer in August were 18-20 :jester:

I've not done any long highway miles without the trailer so can't give figures for that.

cerich · **Posted:** Tue Jan 04, 2011 9:58 am

recheck your brakes

Jeep4ever617 · **Posted:** Tue Jan 04, 2011 10:44 am

I should just break down and replace the front calipers. They are original at 94, 300k. Is there a better after market option or is it ok to replace them them stock ones?

mustang_gt_350 · **Joined:** Tue Jun 01, 2010 8:47 am **Posts:** 191

Jeep4ever617 wrote:

No EVIC so it is hand calculated and I just had new rotors put on and the calipers checked out fine according to my mechanic. I usually let it warm up for 5-10 minutes when its cold but even throughout the hot summer I rarely broke 19mpg with mix city and highway. I am hoping that after I get the Kennedy lift pump and Suncoast TC installed here soon that I can get a good increase by getting the HOT flash done by GreenDiesel.

Lets go pens! :pepper:

Ok a few things.

1. How long is your drive 1 way? (and what roads? kinda familiar with Pittsburgh) The shorter your drive the worse the MPG and the colder temps and short are KILLER on MPG.

2. What brand fuel? additives? and have you tried filling up at other places to compare?

3. The CRD in park/N will burn about 1 quart of fuel at idle per hour. It will be more if its colder and running the viscous heater and your blower wide open if you have your heater cranked. How much more i don't know i can't remember the figure for when it was in Drive at a stop light at idle. I'm not into allowing anything i have idle to warm up other than just enough time to get the oil flowing.(pm if you want my reason)

4. Have you checked around for the possibility of a boost leak?

With all this said above i have noticed with mine driving in somerset county pa (my first winter with it) my MPG is between 18-20 when i was normally this summer around 22-25 or a little more doing the same drives. My odometer is almost 5% off so when i'm at 400 miles I'm really 420. Also i have just noticed a fuel leak on mine when i fill it all the way up. I think the filler tube is either cracked of loose, i haven't checked it out just been keeping it a little under full. It only does it when i let the pump kick off or try to fill to the spout.. Oh yeah, are you filling it to where you can see the fuel level in the filler neck? And it works best if you do it at the same pump so the angle is right each time for the tank to purge air pockets. With my powerstroke i could count on a 3-4mpg decrease in the winter time between the colder temps and winter blend fuel. I had any longer road trips to check my MPG with winter fuel and a trip, will be driving to the pit airport on thursday so i'm looking forward to seeing what i can get as compared to summer.

Joe Romas · **Posted:** Tue Jan 04, 2011 2:09 pm

Mustang_gt_350

Re your fuel drip when filling into the neck.

Get down on the ground under your filler and look up to where the filler hose goes up, Then check the location of the smaller vent hose. As I remember it's cliped to the larger rubber hose going to the filler neck. When I had my tank out for the intank lift pump I noticed you can raise it up. Just make sure you have dirty cloths on when you reach up there :mrgreen:

Unlike gasoline, diesel does not evaporate so there's no evaporitive emmision stuff on the vents of our kj's

mustang_gt_350 · **Joined:** Tue Jun 01, 2010 8:47 am **Posts:** 191

Joe Romas wrote:

Mustang_gt_350

Re your fuel drip when filling into the neck.

Get down on the ground under your filler and look up to where the filler hose goes up, Then check the location of the smaller vent hose. As I remember it's cliped to the larger rubber hose going to the filler neck. When I had my tank out for the intank lift pump I noticed you can raise it up. Just make sure you have dirty cloths on when you reach up there :mrgreen:

Unlike gasoline, diesel does not evaporate so there's no evaporitive emmision stuff on the vents of our kj's

I actually was just going to post a question about that vent. I crawled under it today to look around and noticed that it wasn't attached to anything so i got my flashlight and saw it had a vent top. i was going to ask if it had a check valve in it to allow only air to escape but that would be hard as i think thats the only vent it has on the tank so it would have to let air out and in? I'll have to run out and see if i can slide the clip up farther and i'll go fill it up. I bet thats been my problem. I may just cut it and extend it up into the filler door if i get a chance when it warms up around here. Then i know it is at the same level as the cap. I'll try to slide it up and i'll fill it up in the next day or 2 and see if it lets a puddle. I never noticed it doing that before when i first got the jeep this spring. Hopefully thats it and its not at the top of the tank where the breather connects, i really HATE dropping fuel tanks.

thanks for the idea.

dgeist · **Posted:** Tue Jan 04, 2011 5:27 pm

Jeep4ever617 wrote:

No EVIC so it is hand calculated and I just had new rotors put on and the calipers checked out fine according to my mechanic. I usually let it warm up for 5-10 minutes when its cold but even throughout the hot summer I rarely broke 19mpg with mix city and highway. I am hoping that after I get the Kennedy lift pump and Suncoast TC installed here soon that I can get a good increase by getting the HOT flash done by GreenDiesel.

Not that it makes a huge difference, but the 5-10 minutes of warm-up are probably not doing you any good and definitely use fuel. The little diesels will barely put off enough heat to KEEP themselves warm under idle conditions. The act of "warming up the engine" is a carryover from old days when oil viscosities (especially with organics, which the CRDs don't use) would be really inconsistent until the engine was at operating temperature. By NOT warming up your engine, you risked damage. Oil technology/quality has improved dramatically and the current thinking is the best way to warm the engine up is to just let it idle for a few seconds and then go drive it. Obviously, the transmission and such won't operate optimally until fully warmed, but then idling doesn't really bring the tranny up to temp either

You can get the same warm-up benefit by plugging in your block heater (on a GFCI outlet and a timer) and run it for a few hours each morning or whenever it is you start your day.

Dan

Jeep4ever617 · **Posted:** Tue Jan 04, 2011 6:41 pm

Anyone do a frame rail style Lift Pump install? I'm going to install mine in a few days and I could use some detailed instructions on fuel line connection-I'm an amateur Haha. Thanks for all the input guys.

Need help and some opinions please

Who is online