Fuel Guzzler

[Rodd]

Okay so what is causing my bad fuel economy?

Injectors 30-40k miles
Clean filters
Good LP
Have a T/M
Clean air filter

I was thinking I could adjust the T/M and take some boost out of it to see if that changes the economy. Any other suggestions?

 

[ak diesel driver]

how much boost are you running?

 

[buddy]

Important boost value would be when cruising how much boost do you have.

also, injectors can turn crap in 30,000 miles and be dribbling rather than spraying. I would suggest taking out the 4 driver side injectors and have them tested for pop pressure, spray pattern, chatter and leaks at low pressure.

 

[Rodd]

When cruising I think the boost is 3-4. I'll have to look at the gauge the next time I have it on the fwy.

 

[Turbine Doc]

They have about 30k on them. They were rebuilt's from Diesel pro at the place.

Hmnn not good last time I visited with DP & talked to him in person @ the PF shop he wasn't real happy his boss was buying injectors from overseas source and why PF shop can sell at a good price on ebay, FWIW PF shop also no longer a authorized Stanadyne shop either, they work on their stuff but not a factory shop any longer.

I don't go to old site anymore & I have long since forgotten my password even if I wanted to visit there, so I can't generate or recieve PMs there.

So you may want to PM DP there yourself, but since he's an employee he also may not communicate this for fear his boss might not want him talking about the source either, and get his thoughts on where the injectors came from originally,

If from overseas source as I suspect, 30K life is what you may expect from them and you may be due for a new set, maybe pull a couple of the easiest accessed ones and have them pop tested. Now if DP rebuilt the injectors himself, they should be good to go, but if you got shop remans from inventory those are "outsourced" remans most probably.

DP is a good guy and has good advise I don't know why he didn't migrate over here with rest of us; I invited him to come over a few times, but I also know he doesn't spend a lot of time on many forums so probaly chose to stay at the one forum.

 

[buddy]

I discussed marine injectors with DP. What he had to say about what the shop does was terrible. And although he tried to prove marine nozzles did nothing, his results when interpretted correctly proved the marine injectors output more fuel. So although he probably does good work, I wouldn't purchase from the shop.

Ultimately not everyone has the same idea on what the standard for rebuilding injectors should be. Balancing them is important and thats a small tolerance, +/- 25psi is an adequate window, but most shops may work off a +/- 100 or general area pop spec as to get it done quicker. And if you are running 15+ psi with a performance PCM on a standard compression ratio engine then you really need higher pop pressures too, or you'll likely be burning the tips up faster.

 

[Brooklyn Tow]

OT;

Mr. Peabody Avatar.....:hihi::thumbsup:

I invited him and asked why he didn't make the move.....Basiclly like Tim said, and he wasn't happy with all the conflict in the begining.

His input is missed....Great guy.

 

[Rodd]

Hmnn not good last time I visited with DP & talked to him in person @ the PF shop he wasn't real happy his boss was buying injectors from overseas source and why PF shop can sell at a good price on ebay, FWIW PF shop also no longer a authorized Stanadyne shop either, they work on their stuff but not a factory shop any longer.

I don't go to old site anymore & I have long since forgotten my password even if I wanted to visit there, so I can't generate or recieve PMs there.

DP rebuilt them himself about 3 yrs ago. He also told me where I could get bosch marine tips if I wanted to get them for the next time around. I have the marine tips rebuilt and ready to go I am just waiting to find some time to do them and I wanted to wait till I got a new pcm.

So you may want to PM DP there yourself, but since he's an employee he also may not communicate this for fear his boss might not want him talking about the source either, and get his thoughts on where the injectors came from originally,

If from overseas source as I suspect, 30K life is what you may expect from them and you may be due for a new set, maybe pull a couple of the easiest accessed ones and have them pop tested. Now if DP rebuilt the injectors himself, they should be good to go, but if you got shop remans from inventory those are "outsourced" remans most probably.

DP is a good guy and has good advise I don't know why he didn't migrate over here with rest of us; I invited him to come over a few times, but I also know he doesn't spend a lot of time on many forums so probaly chose to stay at the one forum.

DP rebuilt these himself about 3 years ago. He also told me where I could get bosch marine tips. I have them rebuild ready to go in, I just need to find some time to do them.

 

[Rodd]

Well after 4 tanks here is what has happened since the stat change:

1st tank increased from 10-11.5 mpg

2nd tank increased to 12.5 mpg

3rd tank increased to 13.5 mpg (Part of this was towing a 6x9 7ft tall enclosed trailer w/ about 500 lbs about 60 miles and then returning 60 miles empty between 60-65 mph)

4th tank increased 18 mpg ( I got 17 my first tank after my racor mod, then things started going downhill) This one my wife had to drive me to work 32 miles round trip 3 total trips on mostly back roads with only about 6 signal lights. Speed limit range was 45-55 mph. The rest was 5 mile or less trips by my wife in town.

I topped off the tank each fill up as to be sure it was full. I usually fill up between ever 300-400 miles.

We'll see how the next tank goes.
I did top off my tank

 

[buddy]

It sounds like maybe you were going through some bad fuel, or you just changed back to summer blend diesel. That is a drastic change if it were just winter blend related.

 

[great white]

Well after 4 tanks here is what has happened since the stat change:

1st tank increased from 10-11.5 mpg

2nd tank increased to 12.5 mpg

3rd tank increased to 13.5 mpg (Part of this was towing a 6x9 7ft tall enclosed trailer w/ about 500 lbs about 60 miles and then returning 60 miles empty between 60-65 mph)

4th tank increased 18 mpg ( I got 17 my first tank after my racor mod, then things started going downhill) This one my wife had to drive me to work 32 miles round trip 3 total trips on mostly back roads with only about 6 signal lights. Speed limit range was 45-55 mph. The rest was 5 mile or less trips by my wife in town.

I topped off the tank each fill up as to be sure it was full. I usually fill up between ever 300-400 miles.

We'll see how the next tank goes.
I did top off my tank

That is quite an increase.

Mind if I ask what the final gearing is on your truck?

 

[Rodd]

That is quite an increase.

Mind if I ask what the final gearing is on your truck?

I've got 410's.

 

[Rodd]

It sounds like maybe you were going through some bad fuel, or you just changed back to summer blend diesel. That is a drastic change if it were just winter blend related.

We don't have winter blend in Sacramento, do we? I was getting 10 mpg's for the last year and a half so I don't think it was a winter blend since I got the same mpg's last summer.

 

[great white]

I've got 410's.

Interesting.

I've got 4:10's and never seem to break 13-14 mpg.

Well, unless I'm towing the TT, then I get 10 mpg......

 

[Rodd]

Interesting.

I've got 4:10's and never seem to break 13-14 mpg.

Well, unless I'm towing the TT, then I get 10 mpg......

Tell me about it. Like I said I got 17 right after adding a racor filter and it has sucked since. Then fix the ffm leak and change the states and 3 tanks later I'm at 18. Go figure. The next tank will be about 10 again.

 

[Rodd]

Well I think I found my problem. Around town my wife is getting 11-12. When I take it on the freeway I am getting 16-17. I think I need to bite the bullet and get an upgraded pcm and it will get a lot better.