Multiple Misfire after turbo install??
Thread Starter
Teching In
Joined: Jun 2014
Posts: 25
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From: Wisconsin
Multiple Misfire after turbo install?? First let me say hi to everyone, I just registered but have been lurking here for awhile and have found a lot of help about different things from searching here, that being said I have not found anything for my current problem.
I have an 04 Silverado ss, In the last 5 months I have installed a built 4l65e, i6 converter and a new t-case. 3 weeks ago I started adding a front mount turbo setup, got it all done a couple of days ago and started it and it runs very poor. Before the turbo build it ran great, I am running 5 psi off of the wastegate, stock injectors and pump until I get it running right, engine is bone stock, I have hp tuners, aem wideband, no cats and rear 02s deleted. I have b1s1 02 signal wires tapped into bank b2s1. If I start the truck even at idle It runs very poor almost like a big old school lumpy cam, rough idle, smells very rich and after a brief minute of idle the afr settles around 11.5 -12.0 the second I touch the throttle it will dive down to 10.5ish. If I try to drive it it stumbles and and barely moves unless I go wot and it clears up a bit and goes. I have my wastegate and bov vacuum line t'd into the line at the back of the manifold. I just installed new tr6 plugs today and new wires with no difference. I know this is probably something I have done as the truck ran perfect before the turbo, any help or suggestions are greatly appreciated, thank you.
I have an 04 Silverado ss, In the last 5 months I have installed a built 4l65e, i6 converter and a new t-case. 3 weeks ago I started adding a front mount turbo setup, got it all done a couple of days ago and started it and it runs very poor. Before the turbo build it ran great, I am running 5 psi off of the wastegate, stock injectors and pump until I get it running right, engine is bone stock, I have hp tuners, aem wideband, no cats and rear 02s deleted. I have b1s1 02 signal wires tapped into bank b2s1. If I start the truck even at idle It runs very poor almost like a big old school lumpy cam, rough idle, smells very rich and after a brief minute of idle the afr settles around 11.5 -12.0 the second I touch the throttle it will dive down to 10.5ish. If I try to drive it it stumbles and and barely moves unless I go wot and it clears up a bit and goes. I have my wastegate and bov vacuum line t'd into the line at the back of the manifold. I just installed new tr6 plugs today and new wires with no difference. I know this is probably something I have done as the truck ran perfect before the turbo, any help or suggestions are greatly appreciated, thank you.
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Joined: Nov 2003
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From: Norn Iron
It should be safe to say it is something you have done. But you'd need to go back and look through the exact things you have changed, or may have disturbed that can affect running the way you describe.
the physical turbo install is not one of them.
You say you have HP Tuners....but have you actually changed anything from the original tune that was last working ?
Can you restore it to the tune that was working ?
Although cold start and running will be richer than a hot start/running. Have you made any tuning changes that have made it rich ?
Was it like that before ?
the physical turbo install is not one of them.
You say you have HP Tuners....but have you actually changed anything from the original tune that was last working ?
Can you restore it to the tune that was working ?
Although cold start and running will be richer than a hot start/running. Have you made any tuning changes that have made it rich ?
Was it like that before ?
Thread Starter
Teching In
Joined: Jun 2014
Posts: 25
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From: Wisconsin
I have not changed anything tune related since the turbo install, I did reflash back to the base tune just to be sure with no result.
What I mean by "tapping the 02" is I ran the signal wires from the upstream 02 sensor on the driver side ( I believe pin A and B) to the passenger side upstream which is mounted in the bottom of the down pipe. If I remember right it is pin A and B on both connectors, should be both signal wires, purple and tan. I thought this would just make both 02's read from the passenger side. Is this not right?
As soon as I get done here I will fail the maf and see what happens, thanks for the help.
What I mean by "tapping the 02" is I ran the signal wires from the upstream 02 sensor on the driver side ( I believe pin A and B) to the passenger side upstream which is mounted in the bottom of the down pipe. If I remember right it is pin A and B on both connectors, should be both signal wires, purple and tan. I thought this would just make both 02's read from the passenger side. Is this not right?
As soon as I get done here I will fail the maf and see what happens, thanks for the help.
Never heard anything like that before. I run open loop speed density so I don't use o2's.
Do you have the 2/3 bar operating software applied with the correct map sensor? Boost referenced regulator?
Do you have the 2/3 bar operating software applied with the correct map sensor? Boost referenced regulator?
Thread Starter
Teching In
Joined: Jun 2014
Posts: 25
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From: Wisconsin
I unplugged the maf and it makes no difference drives the same, when the truck is first started it runs "ok" and can be driven without getting into boost for about 30 seconds of so and then starts bogging down and cutting out. If I pull over turn it off for a few secs it will do the same all over again.
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Teching In
Joined: Jun 2014
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From: Wisconsin
I do not have that, it is completely stock with the exception of the turbo, it runs this way even out of boost, I think I may try a different mass air flow sensor as well as mounting the o2 sensor on the driver side in the crossover pipebefore the turbo, it seems like it should run good out of boost since that is the only thing that has been changed.. idk??
Thread Starter
Teching In
Joined: Jun 2014
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From: Wisconsin
Oh and new plugs only have about 1 hour of run time on them, every single time without fail when it starts acting up I can slip it into neutral turn the key off, turn it back on and it runs great again for 30-40 more seconds
I do not have that, it is completely stock with the exception of the turbo, it runs this way even out of boost, I think I may try a different mass air flow sensor as well as mounting the o2 sensor on the driver side in the crossover pipebefore the turbo, it seems like it should run good out of boost since that is the only thing that has been changed.. idk??
-ditch the MAF
-undo whatever wiring you did to the o2's
-get a 2 or 3 bar MAP
-HP Tuners upgrade to use the 2 or 3 bar MAP
-get a boost referenced regulator
-get appropriate injectors and correct the data in the tune
-set it up for open loop speed density and tune with the wideband
Thread Starter
Teching In
Joined: Jun 2014
Posts: 25
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From: Wisconsin
I have 42lb injectors and a walbro 255 but I wanted to get the basics done and up and running before I complicate it with more things. I am learning hp tuners as I go, I will still probably get it tuned locally but I would like to learn as much as I can in the meantime. This setup with this low of boost can work with a maf I thought, up to about 10 psi? Im just trying to get what I have on right now to work. Im going to mount the driverside 02 just after the manifold in the crossover pipe that goes across the front of the engine and just extend the harness, would that 02 cause this kind of issue? Thsts the only thing different that I can think of other than tee ing into the vacuum line at the rear of the intake.
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Joined: Nov 2003
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From: Norn Iron
So it's using all standard sensors, standard injectors, etc etc...
There is no baseline you need to find, as the standard tune should still be perfectly fine at idle, light loads etc.
It should be running fine
There is no baseline you need to find, as the standard tune should still be perfectly fine at idle, light loads etc.
It should be running fine
I would start with the o2 and unsplice what you have done and hook both up. That seems to be what you changed. Had a o2 wire get smashed by a lift arm one time and had a identical problem.