Pyro and fueling concern...

[1992-6.9]

I installed a pyro in the driver's side manifold, is that a good place for accurate readings? I got a max reading today on some hills in 90* heat of 1250... Right at the limit I know, but with the A/C on and music holding 65 wasn't bad for a 22 year old motor ;p. Anyways, I got off the highway, andstopped at a stoplight and the truck started to stutter like it was low on fuel and sucking air. Did it last night at the local fastfood joint too. Checked and the tank was 3/4 the way full. Okay, so I bump the idle speed up a bit waiting and it kind of went away. I think I was sucking air somewhere, but it has NEVER done this Up the hill after the stoplight it just held 35, so I clicked on the hazards and narrowly avoided being run down by GMC, and pulled off. Idled on the shoulder for a minute and everything was normal. Coming down from the mountains last night, I also noticed a ticking noise that varied linearly with engine speed, if that helps at all... Sorry for the long post....

 

[Michael Fowler]

Are you still using the factory fuel pump and the factory water seperator? My guess is that you are sucking air in at the water seperator. Those who have installed an electric fuel pump right at the fuel selector valve under the driver's feet can tell you, it is one of the best, and simplest mods you can do. Any leaks in the fuel lines now become visible as the lines are pressurized--rather than sucking air into the system. The added benefit is that you can fill the filter much easier when you change fuel filters.

 

[Diesel JD]

From your name I'm guessing you have a 6.9 in a 1992, which would basically eliminate the fuel filter concern. That was a very good system that I wish I had... Back to your problem...if you just now installed a pyrometer, but you are driving exactly like you've always been, you have probably been doing this a long time and just didn't know it, so I doubt you hurt anything just with your little test drive, though 1250 if I knew it was that high I would be bothered. The ticking and low power, I wonder if your injectors might be giving you problems. Also check cheap and easier first, you might have a plugged up fuel filter, causing restriction, advanced timing(the tick) and low power, not enough fuel. Even supposedly clean diesel sources, you can still get a nasty tank full. Good luck solving it,
J.D.

 

[1992-6.9]

Thanks much. I will start cheaper...fuel filter first. I assume holley red is what I should go with fuel pump wise. How hard is that?? and expensive?? Truck has around 300,000 on it right now. Yeah, sitting on 1250 has me a tad concerned, but I have been pulling the truck that ******* a normal basis so I still have all 8 running is a good thing. My 0-60 time at a mile high is hovering around 25 or so seconds. F-250 4x4 supercab ZF5 w/ Aurora 2000 turbo. I do not have a boost gauge, as this pyro seems to me like a waste of $$ to only find out I can't add more fuel. I have no idea what gears are in it, the sticker is long gone...and last time I checked the tag on the diff was ripped off. Everything is factory so far, excluding the turbo...

 

[EvergreenRanch]

holley red works, but theres a metal fuel line which i have been told isnt supportable with the holley red that will vibrate and break over time.......

 

[1992-6.9]

What is the best inexpensive fuel pump I should add??

 

[Diesel JD]

You can splice in any electric pump. Most prefer Holley red, but others have had good success with a cheapie off teh shelf pump from Napa or one of the other parts houses. the important thing to remember here is 1) these pumps push fuel better than the pull it, so mount the pump level with your fuel line and as near to teh selector valve as practical. 2) you need to fuse whatever source of 12VDC that you use to power the pump and establisha good ground. the package will tell you what fuse rating to use. I use teh cheap inline glass bulb buss fuses. 3) You need to put an inline filter before the fuel pump if so directed by the MFGr. You can either use a toggle switch directly from the battery or a wire that is hot with the key on, through a fuel pump relay to the pumps red lead, black to ground. If you are concerned about teh mech. lift pump being dead, you can test it based on how much fuel pressure the pump is providing. Someone here should know the appropriate specs, but I can't remember for sure. I really think you should have a boost gauge with that turbo even if you can't put any more fuel in. If you have EGTs that high and not enough boost and power, I would look for a problem with the exhaust or intake system. Again, start cheap, any breaks inthe exhaust piping or a dirty air filter. Those Aurora 2000 turbos replaced the ATS wastegated unit. I think they are slightly different but probably follow the same guidlines. Should have around 11-13# max boost in near stock trim with the fuel screw nearly maxxed out. If you adjust the wastegate you can get closer to 15-18 but you'll be changing headgaskets on stock 6.9 bolts very soon at those boost levels and maybe buying pistons....., unless you ahve studs and a built engine you want to stay below 12-13 boost at max, and 10 for any length of time. Boost gauges are cheap, pistons are not. Good luck,
J.D.

 

[1992-6.9]

Thanks. Seems my air sucking ordeal is gone after changing the filter for some reason. (scratches head). Doesn't make sense though. I have the same 0-60 time of 24 seconds and a 40-60 time of about 11 seconds. I realize it isn't a rocket but could my injectors be getting tired hence the tick or maybe my ip??

 

[Agnem]

That 1250 is a real reading, and one worthy of concern. NA engines do run hot, and with the factory pump setting will seldom max out past 1150, but you should make an effort to keep those temps down. I like to think that most pyrometers are only accurate within 100 degrees, so assuming yours could possibly be reading 100 degrees LOW, I'd make 1150 my personal upper limit. Now some will tell you that the 6.9 will run at 1250 all day, and that very well may be true, but alluminum melts at 1220 degrees, and I'm just not comfortable relying on the piston cooling jets to be the only thing keeping my pistons from turning into alluminum blobs at the bottom of my oil pan.

 

[1992-6.9]

I will buy myself a boost gauge perhaps today after work. Any old one would work?? I have seen ones at the local parts place that goes to 35, but seeing as the boost hovers around 10 normally it would barely move the gauge. It also has vacuum on the gauge too. Fuel filter is new, air filter resctriction gauge is fine unless it's broken, pump is timed correctly according to ATS, just feels slow and hot. The exhaust is a 3"DP leading directly to a straight through 3" muffler, then to a 4-3" reducer then 4" out. It has a really bad drone on the highway though. I was with a 4" straight DP back, and it was really nice sounding, but had an annoying loud snapping noise around 2700 rpms so I put in the muffler. Odd thing is, with the muffler it is whisper quiet, but quicker than w/o the muffler....

 

[Diesel JD]

Okay, so did your ticking noise go away with the sucking air problem or is is it still there? Changing the filter fixed your sucking air fuel starvation issue because when the filter media is full of contamination, it really restricts your fuel flow allowing some air in with the fuel stream. This can cause the the timing to be advanced, in fact from my understanding this is how the cold timing advance on our trucks works. Its really not enough to hurt anything as long as you were within specs before and its sounds like you are. Eventually this condition stalls out the motor if you don't address it. As far as a boost gauge goes I would say you should get any one intended for a turbo. they are pretty cheap and there are some nice ones on egauges.com for <$50. Personally I would go with one that measures 0-15 or 0-25, you'll be able to read it the easiest.

 

[1992-6.9]

Forgot to mention that. I topped off all the fluids and changed the filter at the same time. Ticking is gone. Oil was a bit low. The previous filter media was black, so I assume that would mean it was done. Gauge wise, I got busy today, too much to do so I didn't get a boost one. Until we know the boost it is putting out, is there anything else that could be making the truck so slow??

 

[Diesel JD]

Okay, so you have changed the fuel filter, how about teh air filter? A restrictred air intake can cause higher EGTs and low power along with poor fuel economy. Are your EGTs still as high as you originally stated? Are you sure that all the trubo components are sealed and that there are no exhaust or boost leaks? If this is the case, you may have to start looking at your fuel system, injectors(pop test don't replace outright) and injector pump. You say the truck is slow, but isit slower than it has been or just not the performance gains you wanted from yoru turbo?

 

[1992-6.9]

I have a new filter in the truck now. No difference there either. The truck has been slow to begin with, but I expected that. With the turbo, I expected a bit more oomph. Compared to what other's seem to be able to pull and stuff, I feel something is wrong. I get the feeling that if I tried pulling a loaded trailer over 1,000 lbs, the truck would be at 35mph in the right lane, kind of like it was empty pre turbo... What is the $$ for pop testing?? I hear it may be free if I remove the injectors. The EGT's haven't changed one bit. When I removed the exhaust from the DP back it had quite a bit more pep to it, but the clutch started to slip at that point... Interesting to note however, If I wrap the tach to redline each gear then shift to 60 my EGT's are about 800*. If I lay into it until 2,500 rpms, then shift each gear, the EGT's are still around 800*. I noticed though, that when I use less than fulll throttle it feels stronger than if I just mash the pedal. Overall, it just feels like something is holding hte truck back...It just pokes along...

 

[f-two-fiddy]

How many miles on the fuel system?
Didja turn the fuel screw up?