Problems
Problems I'm running into starting issues with my supercharged 5.3. The sc is a rebuilt Powerdyne BD11. I'm running the 8100 injectors(42lbs). It's hard to start and it wont remain running. Sometimes the engine backfires horribly, and when Im attempting to start it, the passenger side header collector goes up in flames as if the engine is dumping too much fuel. I've checked all the necessary sensors and pulled the plugs, which were being drowned with fuel. Should the pcm be tuned for the bigger injectors(42lbs) before attempting to start? I've also removed the passenger side head just to be sure that a valve wasnt hung open, and everything appeared to be kosher, but cylinders #2 & #4 had much more carbon built up on both the valves and pistons, 6 & 8 looked as though they were still fresh from the machine shop. Any ideas is greatfully appreciated.
On The Tree
Joined: Jun 2005
Posts: 161
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From: Wasilla AK
from the sounds of it he doesnt need a wide band he needs a flow meter to see how much fuel its dumping
definitely get a base tune for those injectors its like you have a 2 inch pipe and a 4 inch pipe and with the old tune you had to open the 2 inch pipe all the way well now its a 4 inch and when its open all the way its getting twice as much
get that first check for air leaks ect
definitely get a base tune for those injectors its like you have a 2 inch pipe and a 4 inch pipe and with the old tune you had to open the 2 inch pipe all the way well now its a 4 inch and when its open all the way its getting twice as much
get that first check for air leaks ect
I scanned it for codes and there were none. I also switched back to the stock 5.3 injectors for now but still no change. I probably should have mentioned that all of these issues started happening after I installed a set of Harland Sharp roller rockers. Before the rr's the engine would run and start flawlessly. Once it began acting up with the rr's I looked at each one and realized that a few of them were rubbing against the wall of the cylinder heads as if they were sized wrong, and they had made contact with the valve cover. So I removed the rr's, put the stock ones back on and still no dice. At this point I've pulled the head, everything looks ok but Im taking it to the machine shop for an expert opinion. Hopefully it turns out to be one of the valves was hurt by the rr's, because I cant think of anything else that caould be a potential issue.
Heres thre latest: I just got the head back from the machine shop, builder said everything was okay with the valves except that the valve stems were 5 thousandths too long. So I take that for what its worth but now Im wondering if that couldve been the cause of my problems. As I stated earlier, before installing the rr's the engine would start and run without any problems, but once I installed the rr's and the longer pushrods, thats when the problems started. Do any of you guys think that with the too long stems, the rr's and the longer pushrods, this could have created the problems? I wont have any garage time for a day or so, but Im dreading getting the head reinstalled and the problem still existing.
.005 + on the valves is not the problem. How did you determine what the length of the push rods should be? Sounds like you are hanging the valves..
Your problems stated in post #5 have to be corrected, along w/ getting the right pushrods in there.
Are the rr's the correct ratio?
Your problems stated in post #5 have to be corrected, along w/ getting the right pushrods in there.
Are the rr's the correct ratio?
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The aftermarket rr's are 1.85 ratio, but I removed them and the longer pushrods and reinstalled the factory rockers and pushrods but the engine was continuing to do the same thing. I used an adjustable pushrod to determine the length, though Im not really sure I did it correctly. Im going to get the head back on along with the factory rockers and pr's and see if the problem has been corrected, if not then......
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Verdad Gallardo So I paid the machine shop 70 bucks to cut the valve stems down 5thousandths of an inch believing that to be the problem. Reinstalled the cylinder head along with the stock rockers and pushrods, attempted to start the engine and the problem described in post 1 still exist. I got so frustrated today I knocked my back window out with a sledge hammer, I know it wasnt the smartest thing to do but at this point Im ready to junk the project and start over.
I'm running into starting issues with my supercharged 5.3. The sc is a rebuilt Powerdyne BD11. I'm running the 8100 injectors(42lbs). It's hard to start and it wont remain running. Sometimes the engine backfires horribly, and when Im attempting to start it, the passenger side header collector goes up in flames as if the engine is dumping too much fuel. I've checked all the necessary sensors and pulled the plugs, which were being drowned with fuel. Should the pcm be tuned for the bigger injectors(42lbs) before attempting to start? I've also removed the passenger side head just to be sure that a valve wasnt hung open, and everything appeared to be kosher, but cylinders #2 & #4 had much more carbon built up on both the valves and pistons, 6 & 8 looked as though they were still fresh from the machine shop. Any ideas is greatfully appreciated.
You didn't change (or have someone else change) the injector flow rate data using HP tuners or some other tuning package?
You can't install 42lb injectors and keep the stock tune, without it running really bad. You might of wiped out the front oxygen sensor. If you keep running it this way without getting it tuned for the 42's, you're going to need an engine rebuild as you're washing down the cylinder walls with excess fuel. Bob
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ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
I never had the oxygen sensors installed, I would start it and let it run for a few seconds, not a long period of time. But now that you mentioned the excess fuel possibly being the issue it has me wondering.
Until you change the tune you're wasting your time and chasing ghosts.
How can I have the pcm tuned if its not even firing properly? At this point I cant even get the damn thing to start, its only spinning. I'll say again, at this point I have the stock 5.3 injectors and rockers back on the engine and it will not start. So whats the purpose in tuning now. The vats has been turned off, and all the unnecessary emissions were deleted also. Is it possible for the cam or crank sensors to go bad without throwing a dtc?
