wring09 Posted May 11, 2012 Share Posted May 11, 2012 I am a ford asset technician one year in, been learning alot and have my own 7.3 I picked up as a project. It needed injectors so I just got the injectors installed. The truck now cold starts fine and runs "better" but has a miss and makes a "hissing" sound we cannot locate sounds like from motor...injectors are brand new so is IDM batteries and starter...the turbo is shot im rebuilding another one as we speak but I cannot figure out the HISS it also is sending white smoke which is obviously raw fuel by the smell and look of it out exhaust I know HPOP probably still has some air in it but the HISS and the miss do not make since to me it didnt even miss when it needed injectors. I dont have IDS so I havent been able to run any tests or even properly pull codes. Looking for any ideas. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted May 11, 2012 Share Posted May 11, 2012 When the EBPR (the warmup flapper on the turbo) engages on a cold start it will remain engaged until 140ish EOT causing a noticable hissing noise which is normal. Is this your hiss? Quote Link to comment Share on other sites More sharing options...
lmorris Posted May 11, 2012 Share Posted May 11, 2012 Those older ones tend to have sticky EBP valves. Unhook the arm and see if you can move the valve. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted May 12, 2012 Share Posted May 12, 2012 Or unhook the arm and leave it unhooked....... Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted May 12, 2012 Share Posted May 12, 2012 Or unhook the arm and leave it unhooked....... I read a lot that the "thing to do" is to remove the valve completely. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted May 12, 2012 Share Posted May 12, 2012 I wouldnt take that thing out up here in Vermont, it be mighty difficult to keep the windshield defrosted! Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted May 12, 2012 Share Posted May 12, 2012 Are you serious? I know a lot of them in Cleveland that are unhooked, and I've asked several guys if they noticed the difference in heat or warmup time. All said no. I think the EBPR is for 60 passenger school busses (T444E) that really need a lot of BTUs to get it warm inside. Keef: Usually they're tied open with coathanger. Quote Link to comment Share on other sites More sharing options...
wring09 Posted May 12, 2012 Author Share Posted May 12, 2012 Its not the EBPV its engine related and is engine speed...it sounds like air passing so i took valve covers off and ran it that way and still couldnt pin point it...not real sure whats going on and ebpv wouldnt cost the rough idle and smoke Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted May 13, 2012 Share Posted May 13, 2012 Use a length of hose like a crude stethoscope to help localise the noise. Certainly the ebv wont cause a rough idle, but there IS the possibility of having more than one concern... especially on a truck that's nearly 13 years old. Step the first... peek under the dash and make sure that there isn't a chip hanging out the back end of the PCM. I have seen more grief come from these than you can shake a stick at. Don't remain saddled to the IDS if you have a NGS handy. This is a very effective tool for the 7.3 and will give you the same amount of info. Good luck. Quote Link to comment Share on other sites More sharing options...
Fordracer Posted May 13, 2012 Share Posted May 13, 2012 You might have a y-pipe leak or a leak at the y-pipe block that bolts to the back of the turbo. It wouldn't cause a miss but you might have two different problems. If you used Ford reman injectors there is a real posibilty that one of the new injectors are bad. When ever I put in 8 Ford reman injecotrs or a Ford reman engine it seems 2 injectors go bad within 3,000 miles. Quote Link to comment Share on other sites More sharing options...
wring09 Posted May 14, 2012 Author Share Posted May 14, 2012 Jim, my truck does have a chip in back of pcm but it is done right and it is to run the stage 2 single shot injectors I installed. They have 5 year 200,000 mile warranty and cost half what ford remans do. Fordracer I havent check the up pipes yet I need to do that I have considered one of new injectors having a problem or me breaking an o-ring during installation. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted May 14, 2012 Share Posted May 14, 2012 Just so you know.... the first thing I would do is yank the chip. Not to be repetitious but "I have seen more grief come from these than you can shake a stick at". I'm not writing this just to see if my keyboard works. I been doing this shit for 40 years and every time I say "that can't be it" I am proven wrong. If you have a steady miss and no injector kill box, you can use an infra-red thermometer to help identify the cylinder... or, you can unplug each injector in turn (remember that these are 115 volt!!!!) to locate the cylinder. Once you do this you can perform a compression test and/or swap injectors to assist in diagnosis. Just an aside... this truck doesn't sound like a helicopter, does it? Just askin'. Quote Link to comment Share on other sites More sharing options...
wring09 Posted May 15, 2012 Author Share Posted May 15, 2012 I cant yank the chip it runs the stage 2 injectors..you pull it and the truck wont even run. But anyways I can run it on IDS if I bring it home from work one day I know how to identify which cylinder is misfiring but the air hissing doesnt make sense. I have already ran compression test multiple times before installing injectors and cant swap injectors cause they wouldnt be same as one another at all. Stock early 99 injectors are 120cc these are 175cc and these injectors are single shot, originals are split shot. May have screwed up by hot rodding my truck but the single shot is suppose to use way less high pressure oil, get better fuel mileage and pull better with lower egt's.....Im going to pull injectors and make sure I dont have a cracked nozzle or a copper washer didnt fall off. All I can think of at this time or even broken oil ring. Quote Link to comment Share on other sites More sharing options...
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