Help Neeed: Car acting up on dyno (intake, ptb, xpipe, exhaust, stock tune)
03-18-2018, 04:07 PM
#21
Well there are plenty of folks here that ran it with no issues. A few I saw had some problems with all these mods on stock tune but for the most part everyone I talked to was fine. Hopefully it all works out. Thanks!
03-18-2018, 05:23 PM
#22
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Did you get a CEL? If the misfire was severe enough you should be able to dump the ECM history file that will tell you at what rpm it occurred, how often it occurred and at which cylinder it was occurring on. Even if didn't raise a CEL you may still find a Code P0300 with the history file showing the cylinder the misfire was most prominent on. I have been chasing an intermittent power loss on track and the history file showed cylinder #8 misfiring 64 times at about 5200 rpm. That corresponds to my seat of the pants feeling of a soggy response when accelerating in 3rd and 4th gear on long straights where I usually take the engine to just short of red line in each gear. The soggy response slows the climb in rpm and my top speed drops from 150 to 140.
GM Engineering thinks my problem is related to air in the Intercooler even though it is full to the top of the horizontal pipe that goes across the front of the supercharger. When we take the fill cap off the coolant is up into the vertical section the cap is on. GM told us they were going to release a new vacuum bleed tool in January that would make it easier to bleed the air. You can't eliminate the air gap at the top of the reservoir since it is required for expansion when the coolant warms.
Bill
GM Engineering thinks my problem is related to air in the Intercooler even though it is full to the top of the horizontal pipe that goes across the front of the supercharger. When we take the fill cap off the coolant is up into the vertical section the cap is on. GM told us they were going to release a new vacuum bleed tool in January that would make it easier to bleed the air. You can't eliminate the air gap at the top of the reservoir since it is required for expansion when the coolant warms.
Bill
03-18-2018, 09:13 PM
#23
Very interesting Bill. Hope they figure your car out. Yeah mine has no CEL. Next time the guy at the shop will hook everything up so could look at data. He didn’t yesterday. Hope they figure out my car and it’s easy fix . If not putting some stock parts back on. Either throttle body or back to BMS drop in filter.
Did you get a CEL? If the misfire was severe enough you should be able to dump the ECM history file that will tell you at what rpm it occurred, how often it occurred and at which cylinder it was occurring on. Even if didn't raise a CEL you may still find a Code P0300 with the history file showing the cylinder the misfire was most prominent on. I have been chasing an intermittent power loss on track and the history file showed cylinder #8 misfiring 64 times at about 5200 rpm. That corresponds to my seat of the pants feeling of a soggy response when accelerating in 3rd and 4th gear on long straights where I usually take the engine to just short of red line in each gear. The soggy response slows the climb in rpm and my top speed drops from 150 to 140.
GM Engineering thinks my problem is related to air in the Intercooler even though it is full to the top of the horizontal pipe that goes across the front of the supercharger. When we take the fill cap off the coolant is up into the vertical section the cap is on. GM told us they were going to release a new vacuum bleed tool in January that would make it easier to bleed the air. You can't eliminate the air gap at the top of the reservoir since it is required for expansion when the coolant warms.
Bill
GM Engineering thinks my problem is related to air in the Intercooler even though it is full to the top of the horizontal pipe that goes across the front of the supercharger. When we take the fill cap off the coolant is up into the vertical section the cap is on. GM told us they were going to release a new vacuum bleed tool in January that would make it easier to bleed the air. You can't eliminate the air gap at the top of the reservoir since it is required for expansion when the coolant warms.
Bill
03-19-2018, 11:35 AM
#26
Oh wow interesting. How many miles did you have? Mine is only 4K which is really low for something like plugs or fuel pump to be bad. I’ll let my guy know to check that also then. Thanks!
QUOTE=TXRR;1596812687]
QUOTE=TXRR;1596812687]
Fuel pump. Mine did the same thing and
[/QUOTE]
03-19-2018, 12:47 PM
#28
What? That’s insane. You paid out of pocket or under warranty? I would hope under warranty because a new car doesn’t just need a fuel pump after that low of miles. I don’t care what car it is. I’d probably have to put things back to stock to try and prevent the dealership from saying the mods caused the issue.
QUOTE=TXRR;1596814052]
QUOTE=TXRR;1596814052]
I had about 3k miles. This is a common prob. Fuel pump is $1400
[/QUOTE]
03-19-2018, 01:27 PM
#29
I was doing mods when they found the problem. My car was running 500 psi through fuel. Normal is 1900 psi. I just had my mechanic fix it. My family works in the Chevy parts department. I paid $700 for fuel pump with family discount
03-19-2018, 01:28 PM
#30
03-19-2018, 01:38 PM
#32
03-19-2018, 08:53 PM
#35
Torco will jack you plugs up trust me, it turns them to rusty looking color. It will cause misfires,KR.
i only used two bottles over 2months,it ran like a champ but after time it started causing problems.
BTW do you gerbal with the white q50 in HI
goggle it torco has some chemical that creates that rusty look.
i only used two bottles over 2months,it ran like a champ but after time it started causing problems.
BTW do you gerbal with the white q50 in HI
goggle it torco has some chemical that creates that rusty look.
03-19-2018, 09:57 PM
#36
That’s weird because I’ve been using Torco for a very long time now. Used it on both of my GTR’s and never had a problem once. I am aware of the orange residue that it leaves on the plugs but spoke to several shops and they said it’s normal and there is no harm. Many used for 100K plus miles. I only used it for 21K miles on my first GTR and 16K miles my second GTR, but many have used a lot longer. If anything it’ll prevent misfire/KR due to the higher octane rating. What kind of problems did you experience? I’ve met the white Q50 before at a car meet.
QUOTE=twostep361;1596817690]Torco will jack you plugs up trust me, it turns them to rusty looking color. It will cause misfires,KR.
i only used two bottles over 2months,it ran like a champ but after time it started causing problems.
BTW do you gerbal with the white q50 in HI
goggle it torco has some chemical that creates that rusty look.[/QUOTE]
QUOTE=twostep361;1596817690]Torco will jack you plugs up trust me, it turns them to rusty looking color. It will cause misfires,KR.
i only used two bottles over 2months,it ran like a champ but after time it started causing problems.
BTW do you gerbal with the white q50 in HI
goggle it torco has some chemical that creates that rusty look.[/QUOTE]
03-19-2018, 11:19 PM
#37
Well In my case it did affect performance, it had misfire on topend.
some misfire at low rpms.
It would pop like pop corn popping.
Not a lt4 but.
I had a Q50 3.0t tuned.running e40 and the torco when turn up a bit more.
so I was running about 110 octane easy.
i put some oem gtr plugs problem solved
it only had 7k
some misfire at low rpms.
It would pop like pop corn popping.
Not a lt4 but.
I had a Q50 3.0t tuned.running e40 and the torco when turn up a bit more.
so I was running about 110 octane easy.
i put some oem gtr plugs problem solved
it only had 7k
Last edited by twostep361; 03-19-2018 at 11:20 PM.
03-20-2018, 02:50 AM
#38
Oh wow. Very interesting!
Well In my case it did affect performance, it had misfire on topend.
some misfire at low rpms.
It would pop like pop corn popping.
Not a lt4 but.
I had a Q50 3.0t tuned.running e40 and the torco when turn up a bit more.
so I was running about 110 octane easy.
i put some oem gtr plugs problem solved
it only had 7k
some misfire at low rpms.
It would pop like pop corn popping.
Not a lt4 but.
I had a Q50 3.0t tuned.running e40 and the torco when turn up a bit more.
so I was running about 110 octane easy.
i put some oem gtr plugs problem solved
it only had 7k
04-07-2018, 03:35 PM
#39
Wish me luck. Finally got my car back in the shop. Hopefully they’ll be able to figure out the problem and have it running 100%. They are going to make a pull with wideband and datalogger hooked up. Depending on what they see will dictate what we to do next. If it runs lean, then they’ll put my stock intake back on with BMS drop in filter. If it's picking up a bunch of misfire/knock they’ll look at changing the plugs. Really hope it gets figured out today.
04-07-2018, 06:08 PM
#40
Super Happy 
My car is now running at 100%. They swapped the plugs and boom no more stuttering or crazy dips in upper RPM’s. Even better is I didn’t have to put any of the stock parts back on. I can sleep good now. LoL. Thanks everyone for the help and support!! Car pulls even harder now. Put down a healthy 574hp and 599tq which isn’t bad at all. 600hp/600tq would have been amazing but I’ll take these numbers for very minimal mods and on stock tune. Every dyno reads different so hard to compare to others with a bit more hp/tq. Mods are Katech ported throttle body, Injen Technology intake, Borla X pipe and Magnaflow exhaust.
My car is now running at 100%. They swapped the plugs and boom no more stuttering or crazy dips in upper RPM’s. Even better is I didn’t have to put any of the stock parts back on. I can sleep good now. LoL. Thanks everyone for the help and support!! Car pulls even harder now. Put down a healthy 574hp and 599tq which isn’t bad at all. 600hp/600tq would have been amazing but I’ll take these numbers for very minimal mods and on stock tune. Every dyno reads different so hard to compare to others with a bit more hp/tq. Mods are Katech ported throttle body, Injen Technology intake, Borla X pipe and Magnaflow exhaust.