10-03-2007, 04:53 AM
My truck has had this problem for awhile now. If I stand on it I'll get an initial blast of smoke and then it clears up. But, as the rpms climb the smoke comes back and gets worse and worse until the trans shifts and then it will clean up again momentarily until the rpms start climbing again. This is just the opposite of what I would expect. Sometimes it's not a steady stream of smoke, sometimes it puts out big "puffs" of smoke before it goes to a steady stream all the while the pedal is on the floor. I mean sometimes it looks like a puller dragging a sled down the track.
I'm running a Predator tuner (yeah I know) on the 40 hp tow setting, ITP regulated return with pressure set at 68psi cold, 4" turbo back straight exhaust, Swamps 20* hpop, a 12" S&B open element air filter and stock injectors. That's it.
I've got one of Bob's Turbomaster units set at 24 psi. Otherwise it will just almost go to 30 psi of boost without it. While this is going on EGTs run about 1275* to 1300* tops.
Now one more thing, this truck eats #8 injectors like candy, one about every 10,000 mile or so now.
With a new injector in there the smoke will clean up and stay just a haze throughout the rpm range. But get a few thousand miles on one and it'll block out the light of day as the rpms come up.
I posted about this a time or two before on that other site. Had a few replies and questions about this or that. But it seemed that no one knew what was going on with it and gave up so I thought I would try it here.
Excuse the long post, I just wanted to try and include as much info as possible.
10-03-2007, 04:59 AM
What kind of condition is the trans in? My only thought is that the smoke is coming back at higher revs because the trans is just taking to long to shift, as in slipping, and once it shifts there isn't as much of a load on the motor, due to slippage. I can't explain if it could be the #8 injector... I just thought I would throw it out there.
10-03-2007, 01:17 PM
Have you ever sent the injectors that go bad to someone to take apart and find the problem?
Does boost stay constant while the smoke comes back?
I would probably let it run up to at least 30 psi boost, that may help the smoke at high RPM.
10-03-2007, 06:17 PM
Something going on with that #8 injector is your problem. Who is installing it? Could it be that its not getting seated good, and burning o-rings/ copper washer? And X2 what he said. Adjust that boost up close to 30. Whaty about a fuel problem, air maybe? Gotta be a problem somewhere causing that injector to fail. Either installed wrong, or an air in fuel problem, or something. Stock injectors that are working right shouldnt have much if any smoke at higher rpm's unless you got a boost problem.
10-03-2007, 07:32 PM
The trans is in good shape, no slipping. Especially when I lock the converter manually. No concerns there.
I sent two injectors that I pulled from #8 to Swamps. Jonathon said that there was a poppet clearance issue. He said they machined or corrected the problem and sent them back to me (free of charge) thanks again guys!
I have one of them in the truck now and it has around 10or 11K on it and it needs to come out again. It was the same thing, after I put one that came back from Swamps in, everything was fine......for awhile. No smoke or just a haze at all rpms and lower egts.
Yes the boost is constant as near as I can tell while trying to watch the gauges, the right mirror for smoke and the road ahead. I don't think there is a problem there. The turbo is really loud with this intake and I don't notice any difference in it.
I can't let it go to 30psi, the stock turbo won't last long at all at that level. Been there done that and learned the expensive way.
I am the one doing the wrenching. When removed all the orings and the copper washer all appear to be in good shape with nothing abnormal. With as many of these that I've changed I'm fairly sure that installation isn't a problem.
My stock fuel tank is just that, stock. I have a 91 gallon auxillary tank in the bed with the modified fuel pickup that I run off of 98% of the time plus the regulated return. It makes no difference what tank I run off of, it runs the same on either one.
I might add that cold idle is great, smooth and quiet. After driving for awhile and getting everything up to temp it will idle and run rough at some speeds. It will fail a contribution test everytime but pass the buzz test. This is with a #8 injector that has been ran for a few thousand miles. With a fresh one, it passes.
I've changed the valve cover gasket twice, the UVC injector harness twice and the main harness has been inspected for burned spots or bad pins. Compression on #8 is 410psi. My Blackstone reports come back just fine even for having 500,000 miles on it. I just can't imagine every single injector that I put in there having the same problem. The first two years I owned this truck I replaced #8 twice, each time at about 100,000 miles on the injector. Since then it's just gone downhill.
10-03-2007, 07:34 PM
Racehauler, your avatar. Is that a result of a flood, tornado or a few too many adult beverages?
10-03-2007, 08:55 PM
with 500k... maybe nothing is wrong and we should be trying to figure how to make our trucks do what yours does. :ford:
10-04-2007, 03:49 AM
Nothing special really. I'm kinda anal about maintenance and keeping it clean.
I've always said that a working truck is a happy truck. I'm the second owner. This truck has pulled trailers to earn it's keep since it was brand new, that's all it knows how to do.
10-04-2007, 04:58 AM
Hey Chris, good to see ya here! Got your call, but i was at BTS in Arkansas and not in service. I'll shoot ya a call tomorrow.
Here's my synopsis on your trouble. The poppet clearance gets out of spec, as your rpms increase, so does your pulse width on the injector. The poppet is then allowed to come too far out of the poppet plate and you're bypassing all your HPO around the poppet and out of the top if the injector. This will drop your oil pressure which loweres your atomization and causes the truck to start smoking higher in the rpms. I'm still not sure why that injector keeps going out though. I'm still kicking it around in my head trying to find the answer to what you got going on.
10-04-2007, 01:01 PM
Racehauler, your avatar. Is that a result of a flood, tornado or a few too many adult beverages?
I found that pic when I was poking around on the internet. The caption for it said: THIS IS WHY YOU DO NOT DRIVE DRUNK
And YES it is the WIFE'S Corvette, guess what he won't be doing for a LONG while.
I don't think they were the originator of the picture because the car is clearly a Ferrari :doh:
In your original post you said you had some Turbomaster, I assumed this was some spin off of a Turbonetics turbo. To make the stocker live you will need to keep it at 25 or under like you are doing.
Hopefully someone can give you some ideas of why the popets would be wearing so bad on your #8 injector. That seems very weird to me.
10-04-2007, 03:34 PM
Hey how's it going Brad? A new motor, a trip to BTS and now a $250.00 gift certificate....some guys have it made.
Yeah give me a call whenever you get a chance. If you wanna wait until your free minutes kick in that's fine, just don't call while Survivor is on lol.
Racehauler, the Turbomaster is from Dieselsite.com. It's a spring loaded mechanical wastegate control. Works good too, I can highly recommend it.
That's a good pic in your avatar, when I looked at that I thought WTH?
11-30-2007, 12:02 AM
An update on my long time ongoing # 8 injector problem.
I picked up this old thread to give a little background on what was going on with my truck.
I sent the most recent injector that I took out of # 8 to Brad (trick76cj5) so that he could check it out and maybe figure out what the problem is.
With his permission, here is the message he sent me telling what he found. We were kinda curious to see what y'all thought and if anyone had any suggestions.
"Here is what I found when i got into the injector:
- There was a black "tarnish" on the plunger, this tarnish had been rubbed off on the area where the plunger stroked inside the barrel. The tarnish rubbed off with a little persuasion. The tarnish lined up with the holes in the side of the injector where the fuel enters. On the inside of those holes there was a tarnish build up.
- When I pulled the injector apart, there was a lot of black gritty stuff in the bottom end of the injector. It broke down quickly when rubbed between my fingers to the point that i couldn't see it, but could still feel it.
- All of the parts of the injector on the fuel side past the plunger and barrel and wear on them. The wear shows how the injector is leaking fuel around some of the parts and high pressure fuel is being dumped back into the fuel rail instead of through the injector. There was some substantial errosion of the metal parts in some locations due to this fuel leakage.
The nozzle looks like it's been hot, but not to the point that I would worry too much about it. I know water will do funny things to these injectors. There is a part of me that wonders if maybe the injector cup has a tiny pin hole leak that is letting just a little bit of coolant into the fuel right at the injector, and the injector is digesting that and pushing it through the system. The tarnish could be attributed to the glycol in the coolant kinda "gumming" up in the injector. something else that has me thinking a little bit is maybe there was/is a build up of crud somewhere in the fuel rail that was allowed to build up while the system was dead headed before you did the reg return. .. maybe this deposit is slowly desolving and making it's way through the injector and basically sandblasting the inside of the injector.
The good news was the oil side of the injector looked very good, great clearances and everything. The plunger and barrel looked good as well. I didn't replace any of the O-rings in the injector, but i did put a new copper washer on the injector tip. I gave you a different nozzle and all the lower fuel parts so everything will seal up correctly."
So.....anyone have any thoughts on this? Let's hear it, I've been fighting this problem for a couple of years now. An injector in # 8 only last for 8,000-10,000 miles now.
11-30-2007, 02:45 PM
If he has any of the tarnish or crud saved in somewhere I would send it of for a chemical annalysis. I would assume the places that do oil analysis can do this also because you are looking for the same chemicals that can possibly be in oil.
I would try to figure out what the gunk is before I went to replacing anything.
12-01-2007, 02:25 PM
Well you could pressurize the cooling system with the injectors out and watch that number 8 cup.
12-01-2007, 07:54 PM
Never thought about trying to have the grit analyzed, might be able to save a sample from the next injector I pull out of # 8.
If it's leaking coolant into the injector cup it has to be a tiny leak, I never have to add any coolant, it stays right at the top mark on the tank.
If it was a pinhole leak in the cup wouldn't there be a chance it also would put fuel back into the coolant? I don't see any signs of that.
Where are all the injector/technical gurus at? Surely someone somewhere has run across something like this before.