Still breaking up and backfiring
Was this the cause of the TPS flicker? Had a similar problem on mine for sometime,,,,,,drove me crazy.
Mine is at 13v when it's at full op temp. You can go down to 11.5 without any issues. I wouldn't go down that road at this point.
Check your pigtails and make sure that they are making good contact on your sensors. I just discovered this problem with my TPS today. It has driven me batshit crazy for the last couple months trying to figure out what was going on. Totally intermittent.
Check your pigtails and make sure that they are making good contact on your sensors. I just discovered this problem with my TPS today. It has driven me batshit crazy for the last couple months trying to figure out what was going on. Totally intermittent.
That's enough.. Now, disconnect the converter, and see how far it will push back into the trans. [Mine is an original install, and is at .160" back]. [You MUST determine the cause of this failure, B4 you proceed.]
Then pull the engine, take the pan off while it's still right side up. [So the **** doesn't fall up into the cam, etc.]
Once the pan is off, roll it over, & take a look at the cks wheel and the sensor alignment, w/ the crank full back, and full forward.
The engine WILL have to be completely disassembled, cleaned out, new brgs, etc, installed. Pay attention to the lifters.. they must be flushed, too.
Sorry to see it's more than a quik fix!
Post some pics of the brgs once you get to that point.
Yes and it was so intermitent at first that it could only be seen in a log at 100th of a sec intervals. Just enough to drive me batshit crazy for 2 months. I was just telling a buddy that I was so mad that for 2 weeks, I would walk by her and call her a ****. LOL
Yes and it was so intermitent at first that it could only be seen in a log at 100th of a sec intervals. Just enough to drive me batshit crazy for 2 months. I was just telling a buddy that I was so mad that for 2 weeks, I would walk by her and call her a ****. LOL
to cause loss of cks, and ***** up the firing order....
Now, disconnect the converter, and see how far it will push back into the trans. [Mine is an original install, and is at .160" back]. [You MUST determine the cause of this failure, B4 you proceed.]
Then pull the engine, take the pan off while it's still right side up. [So the **** doesn't fall up into the cam, etc.]
Once the pan is off, roll it over, & take a look at the cks wheel and the sensor alignment, w/ the crank full back, and full forward.
The engine WILL have to be completely disassembled, cleaned out, new brgs, etc, installed. Pay attention to the lifters.. they must be flushed, too.
Sorry to see it's more than a quik fix!
Post some pics of the brgs once you get to that point.
Now, disconnect the converter, and see how far it will push back into the trans. [Mine is an original install, and is at .160" back]. [You MUST determine the cause of this failure, B4 you proceed.]
Then pull the engine, take the pan off while it's still right side up. [So the **** doesn't fall up into the cam, etc.]
Once the pan is off, roll it over, & take a look at the cks wheel and the sensor alignment, w/ the crank full back, and full forward.
The engine WILL have to be completely disassembled, cleaned out, new brgs, etc, installed. Pay attention to the lifters.. they must be flushed, too.
Sorry to see it's more than a quik fix!
Post some pics of the brgs once you get to that point.
I will NOT be reinstalling any of this transmission stuff until I figure this out don't want to risk that again. Anyway I'll make sure I do what you said about tearing the engine down and I'll get some pictures up in the next week or so.
Had this same problem last year. Lost the thrust bearing and crank was moving .050". Would only show up at WOT throttle. Look close at the hub of that spacer where it slips into the end of the crank. Had to machine mine some.
As I mentioned B4, [Does the t-400 have the converter circuit modified to control psi?
Excessive psi will push the verter off the support, and can trash the thrust brg.] Remember to check w/ your trans builder to see if this has been addressed.
Here's a thread from Turbobuick.com, that has some BS posts in it. But overall, it goes into the problem w/ thrust failure due to excessive psi in the T-400.
http://www.turbobuick.com/forums/tra...-bearings.html
Excessive psi will push the verter off the support, and can trash the thrust brg.] Remember to check w/ your trans builder to see if this has been addressed.
Here's a thread from Turbobuick.com, that has some BS posts in it. But overall, it goes into the problem w/ thrust failure due to excessive psi in the T-400.
http://www.turbobuick.com/forums/tra...-bearings.html
Last edited by Old Geezer; Aug 7, 2010 at 06:27 AM.
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Brett Foote As I mentioned B4, [Does the t-400 have the converter circuit modified to control psi?
Excessive psi will push the verter off the support, and can trash the thrust brg.] Remember to check w/ your trans builder to see if this has been addressed.
Here's a thread from Turbobuick.com, that has some BS posts in it. But overall, it goes into the problem w/ thrust failure due to excessive psi in the T-400.
http://www.turbobuick.com/forums/tra...-bearings.html
Excessive psi will push the verter off the support, and can trash the thrust brg.] Remember to check w/ your trans builder to see if this has been addressed.
Here's a thread from Turbobuick.com, that has some BS posts in it. But overall, it goes into the problem w/ thrust failure due to excessive psi in the T-400.
http://www.turbobuick.com/forums/tra...-bearings.html
As soon as I pulled the oil pan off found bearing material in the pickup screen as well as the bottom of the pan good call on not turning it upside down to remove the pan. Pulled the center main cap off bearing was trashed crank had color change from the heat and also developed a nice crack! I'll know later in the week if I'm going to fix the block or not. It may not be worth it to re-build a 1999 orginal LS1 block when I'm trying to make 1000RWHP here in 2010.
Chunk missing out of crank
Chunk missing out of crank
Damn!!! That sucker is TOAST! It's a shame as the crank block look like they've been worked on, too.
Did you buy the engine already assembled? If so, I'd bet it was hurt when you got it.
@1000RWHP, I think I'd look at a 6.0 cast iron, some more CI, and go for it!
Sorry to see the mess....
Did you buy the engine already assembled? If so, I'd bet it was hurt when you got it.
@1000RWHP, I think I'd look at a 6.0 cast iron, some more CI, and go for it!
Sorry to see the mess....
Yea it was a Katech 418CI it's about 5 years old 10K miles or so before I swapped in the T400 and swiftly ended it it's life. That was a dragonslayer crank. Now I need to get a plan together.
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I've nearly reached the end of the road with what to do to solve this. I've brought up this problem at different stages trying to solve it and since it's progressed quite a bit further I'll try again to get someone who might have an idea of what's wrong with.
The problem is every time you get in it WOT and the rpms get around 6K sometimes less it just breaks up backfires sputters and proceeds to like clockwork shoot a flame out the exhaust. Here's the kicker so far we can't reproduce on the dyno only on pavement.
LS1 418CI Camaro
F1A Procharger @17 PSI
TH400 with 730RWHP
96LB Delphi LI Injectors
TR8 Plugs tried all gaps from .018-.030
Tuned for 93 octane have run 112 octane to try and rule out pre-ign
Timing around 16* depending on circumstances have brought it all the way back to 10* again to rule out detonation.
Lonnies twin pumper kit -8 feed with boost reference regulator fuel pressure is good and boost reference is working correctly.
3 Bar MAP
Open loop SD tune
The whole entire wiring harness has been removed checked inside and out and no problems. The PCM has been swapped out as well. Changed the battery and alternator added grounds checked grounds swapped out the + wire to the starter alternator and battery. Starter has been replaced. Crank position sensor has been replaced. TPS has been replaced. Valve springs are patriot dual springs.
The only thing I can say is that when it's relatively cold not heat soaked it doesn't do it. The hotter it gets the easier it seems to do it. One observation and the reason I changed the alternator is the when cold the voltmeter says 14-14.5 once it heats up the voltage 12.5-13 the new alternator does the same thing.
It really seems electrical in nature since it's not just one cylinder dropping off its all of them like there's a major short or it runs out of juice.
The trigger for this was when I re flashed my TQ to a lower stall it was way loose before. This obviously loads the engine more. The tune worked before now it doesn't I did have it retuned on the dyno but only very minor tweaks were needed and it ran perfect. Once on the track it started this.
I know it's a lot of stuff but the pro's around here are giving up and just want to tear everything down to try and find it (which we may do) but any ideas would be greatly appreciated.
The problem is every time you get in it WOT and the rpms get around 6K sometimes less it just breaks up backfires sputters and proceeds to like clockwork shoot a flame out the exhaust. Here's the kicker so far we can't reproduce on the dyno only on pavement.
LS1 418CI Camaro
F1A Procharger @17 PSI
TH400 with 730RWHP
96LB Delphi LI Injectors
TR8 Plugs tried all gaps from .018-.030
Tuned for 93 octane have run 112 octane to try and rule out pre-ign
Timing around 16* depending on circumstances have brought it all the way back to 10* again to rule out detonation.
Lonnies twin pumper kit -8 feed with boost reference regulator fuel pressure is good and boost reference is working correctly.
3 Bar MAP
Open loop SD tune
The whole entire wiring harness has been removed checked inside and out and no problems. The PCM has been swapped out as well. Changed the battery and alternator added grounds checked grounds swapped out the + wire to the starter alternator and battery. Starter has been replaced. Crank position sensor has been replaced. TPS has been replaced. Valve springs are patriot dual springs.
The only thing I can say is that when it's relatively cold not heat soaked it doesn't do it. The hotter it gets the easier it seems to do it. One observation and the reason I changed the alternator is the when cold the voltmeter says 14-14.5 once it heats up the voltage 12.5-13 the new alternator does the same thing.
It really seems electrical in nature since it's not just one cylinder dropping off its all of them like there's a major short or it runs out of juice.
The trigger for this was when I re flashed my TQ to a lower stall it was way loose before. This obviously loads the engine more. The tune worked before now it doesn't I did have it retuned on the dyno but only very minor tweaks were needed and it ran perfect. Once on the track it started this.
I know it's a lot of stuff but the pro's around here are giving up and just want to tear everything down to try and find it (which we may do) but any ideas would be greatly appreciated.
take those plugs and trash them run br7efs gapped out of the box.
And the reason you cant duplicate it on the dyno is because of it seems like it has something to do with your fuel or loose wiring in ur tankwhen force is applied at the rear of the car causing the pump not to pick up the proper amount of fuel or loose wiring connection. Do you have a factory tank? hot wire kit or direct wiring? also have u changed all of your spark plug wires?
And the reason you cant duplicate it on the dyno is because of it seems like it has something to do with your fuel or loose wiring in ur tankwhen force is applied at the rear of the car causing the pump not to pick up the proper amount of fuel or loose wiring connection. Do you have a factory tank? hot wire kit or direct wiring? also have u changed all of your spark plug wires?
backfire, battery, breaking, fuel, intake, ls1, misfires, procharger, replacement, supercharger, tps, turbobuick, unburnt, weak, wot
