99 & up 7.3L Power Stroke Engine and DrivetrainDiscussion of the 99 & up 7.3L Power Stroke diesel engine and drivetrain in the 1999-Up Super Duty trucks and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 7.3L Power Stroke engine.
I know it sound strange, but I have developed a "spark knock". This all started last week when I finally got my truck back after being in the shop for over a month, COMPLETE fuel system replaced from engine to tank,so far so good. Anyways, the day I got it back I noticed it was somewhat louder, but blamed it on the winter fuel. Within a day or 2, whenever Im going up a hill, or something similar, there is a distinct "spark knock" just like the old gassers use to do. I havent noticed any loss of power, or any other problems except for this noise. Any ideas? (NO its not a normal diesel knock, like I said, sounds like a spark knock)
Air getting into your fuel from somewhere. [img]/forums/images/%%GRAEMLIN_URL%%/whistle.gif[/img]
__________________
Early 99' Upgraded to 99.5' F250 XLT SWB PSD, 4x4, GPT38, EBPV Delete, Perf Friction 2-pcs rotors, 4" turbo back exh, Ford AIS, 6leaker OEM cooler, Htr Core by pass valve, Synthetic every fluid (Mobil), Detroit LOCKER, BTS, Lunar Autometer gauges, DP-F6C, 235k mi SVO ConversionUpdated SVO stuff
I would think that, but this came on all of a sudden like. I had the fuel system from front to back replaced, and have put about 300 miles on it since so I would assume all of the air is out of it by now. It was fine up until about 125 miles, just making normal 7.3 racket, then this started
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: IBSTROKIN</div><div class="ubbcode-body">I would think that, but this came on all of a sudden like. I had the fuel system from front to back replaced, and have put about 300 miles on it since so I would assume all of the air is out of it by now. It was fine up until about 125 miles, just making normal 7.3 racket, then this started </div></div>It is not air in the system from replacing the fuel system, it is the replacement fuel system. The OEM system was designed for gas engines from the tank to the pump. Air can leak through the quick connect fittings on a new truck. Is it louder when the tank runs down below a quarter full? Then it is possible the pickup is leaking.
__________________
2002 F350 Lariat CC 4x4 Auto 4.10 DRW, DP-Tuner F5 live tuned stock, quiet, 40dd, 40, 60, 80 tow, 80e and 120r, B&W GN, BrakeSmart, 'pooned tank, tank and pre-pump mods, 2µ Dahl 100 filter, regulated return, BTS dual HPOP, AC singles with EDM 34 lpm nozzles, AIS, H2e, Spearco 6.0 IC, Hypermax 3.5" dp--> MBRP 4" 304SS exhaust, BTS tranny, 203º T-stat, Chevron ELC, coolant filter, Oilguard bypass with Schaeffer 9000, WranglerNW 200 amp alternator & Optima group 31 batteries, Nippon-Denso starter, SPA gauges, SteveRacer mods, Hella 80/100W 9007s, Hella Micro DE foglights, 1000FF driving lights, 220W backup lights, Stancor contactor, Michelin XPS Traction tires, X-Springs, Bilstein shox, custom bumpers but otherwise stock. Nov 30 '99 build engine with 16 K miles, Fluidampr, Comp Cam 910 springs, Melling LPOP and ARP headstuds.
A little history: Intank and prepump done about 3 years ago shortly after I bought the truck. HX mod done the same day. Started eating fuel pumps and blowing filter lids last month. Dealership fought it for a month then just out of the blue found a kink that somehow got into the return line.(I thought about it,and the only way I could think of it got there is when I hit a Dalmation shorlty before all this started) They left the intank and prepump the way it was only replacing one hose into the pump. (While the had it, I had them put a filter inline there)You cannot buy just one line from Ford, you have to buy the whole system except for those right at the bowl.( Who had that brilliant idea?)With exception to the line going into the pump, the lines were changed all at one time.A new filter bowl was also installed since the problem of it blowing lids and me putting on new filters and such simply messed up a couple of threads. Thatt what I mean by new fuel system. I did fill it up today, but tank was a little over half full. The knock is only there under light loads, like going up long hills, and slight heavy acceleration like getting on the highway.It just started, did fine for about 125 miles after I got the truck back.It sounds just like a spark knock.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cpaine</div><div class="ubbcode-body">would a FASS fix somthing like this? I think i have the same problem. </div></div>Yes,if your problem is air in fuel.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: IBSTROKIN</div><div class="ubbcode-body">A little history: Intank and prepump done about 3 years ago shortly after I bought the truck. HX mod done the same day. Started eating fuel pumps and blowing filter lids last month. Dealership fought it for a month then just out of the blue found a kink that somehow got into the return line.(I thought about it,and the only way I could think of it got there is when I hit a Dalmation shorlty before all this started) They left the intank and prepump the way it was only replacing one hose into the pump. (While the had it, I had them put a filter inline there)You cannot buy just one line from Ford, you have to buy the whole system except for those right at the bowl.( Who had that brilliant idea?)With exception to the line going into the pump, the lines were changed all at one time.A new filter bowl was also installed since the problem of it blowing lids and me putting on new filters and such simply messed up a couple of threads. Thatt what I mean by new fuel system. I did fill it up today, but tank was a little over half full. The knock is only there under light loads, like going up long hills, and slight heavy acceleration like getting on the highway.It just started, did fine for about 125 miles after I got the truck back.It sounds just like a spark knock. </div></div>Did they keep your mods unchanged? Do you know for sure if your injectors are all in good shape?
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.
Linear Mode
