ENGINE ISSUES AFTER TUNE: NEED HELP - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Vicster · 11-09-2015, 08:36 AM

H

Hocky · 11-09-2015, 08:45 AM

Your open loop stumbling is because your tune is way off with wrong AFRs and it won't run right until the fuel trims are there to "fix" it. The rpm hang is probably related to idle airflow tuning. Either way, both are major failures on the tuner's end.

vicnkathy · 11-09-2015, 08:47 AM

Find another tuner asap. Those are both amateur mistakes..

ZL1Kid_AL · 11-09-2015, 09:34 AM

Is the car stock? Or what's done to it?.. If you haven't added a cam you shouldn't have any of these problems... Even with a cam I think a good tuner would have still addressed these problems

Vicster · 11-09-2015, 10:19 AM

Quote:

Originally Posted by Hocky

Your open loop stumbling is because your tune is way off with wrong AFRs and it won't run right until the fuel trims are there to "fix" it. The rpm hang is probably related to idle airflow tuning. Either way, both are major failures on the tuner's end.

Thank You for your input!!

owhite3003 · 11-09-2015, 10:48 AM

Give Tom Wong a call in Vancouver, he will dial it in for you.
http://www.wongsperformance.com/index.html

Vicster · 11-09-2015, 11:04 AM

Quote:

Originally Posted by owhite3003

Give Tom Wong a call in Vancouver, he will dial it in for you.
http://www.wongsperformance.com/index.html

This is my tuner...

owhite3003 · 11-09-2015, 11:16 AM

Tom is usually spot on, my Z will stumble for a brief second when just starting out cold and I didn't use Tom. Let us know what you find out.

DrkPhx · 11-09-2015, 11:37 AM

I'm sure there's a cam and bigger TB in the list, but can you list your mods?

DrkPhx · 11-09-2015, 02:08 PM

Now that's a mod list. Well done.

Assuming your cam has a wide LSA with low or negative overlap that should be relatively easy to dial in along with a 90mm TB. As mentioned above the cold start stumble is in open loop which uses the VVE table. It just takes time to dial it in because the engine temp rises so quickly on start up. The second issue is more concerning especially the surging. Since you already paid him to tune, I would bring it back with the specifics you listed here and ask him to iron it out.

DrkPhx · 11-09-2015, 02:43 PM

I like the specs. -5 overlap is considered mild for this motor. Those are good lobes for this application. Should have a nice and quiet valve train. The second issue could be a couple of factors depending on exactly when and where it occurs. Assuming the fueling is correct, it could be spark timing through a few tables along with the idle airflow table noted above. When you bring it back ask him to datalog while you drive the car so you can point out the problem areas. Hopefully he allows that and it will help a lot.

camaro500 · 11-09-2015, 03:17 PM

Has the car been on the dyno or remotely tuned? If remote, then data log it and send your tuner the data logs. If he still does not correct the situation then I would suggest using one of the reputable tuners on this forum. They can do a great job remotely by just exchanging logs.

Vicster · 11-09-2015, 03:17 PM

Quote:

Originally Posted by DrkPhx

I like the specs. -5 overlap is considered mild for this motor. Those are good lobes for this application. Should have a nice and quiet valve train. The second issue could be a couple of factors depending on exactly when and where it occurs. Assuming the fueling is correct, it could be spark timing through a few tables along with the idle airflow table noted above. When you bring it back ask him to datalog while you drive the car so you can point out the problem areas. Hopefully he allows that and it will help a lot.

I am trying to set up a saturday appt. so I can drop the car off friday night, it should be nice and cold in the morning. Data logging during a drive is a great idea. He should be able to see exacty what is causing the rpm to jump up.

Thank you, Victor

DrkPhx · 11-09-2015, 04:03 PM

^^^ Surprised there was no street tuning done with a cammed car.

11-09-2015, 08:36 AM	#1
Vicster Drives: 13' ZL1 Join Date: Jan 2013 Location: . Posts: 396 View My Garage	ENGINE ISSUES AFTER TUNE: NEED HELP H Last edited by Vicster; 05-09-2024 at 06:32 AM.

11-09-2015, 09:34 AM	#4
ZL1Kid_AL Drives: 2014 ZL1- Summit White M6 Join Date: Aug 2014 Location: Thornton, Colorado Posts: 462	Is the car stock? Or what's done to it?.. If you haven't added a cam you shouldn't have any of these problems... Even with a cam I think a good tuner would have still addressed these problems __________________ 750whp @ 13psi Garage Built on Jack Stands.. 850++ 100 shot of sauce

11-09-2015, 03:17 PM	#12
camaro500 Drives: 2017 Jaguar F Type R Tuned 498awhp Join Date: Apr 2013 Location: Canada Posts: 871 View My Garage	Has the car been on the dyno or remotely tuned? If remote, then data log it and send your tuner the data logs. If he still does not correct the situation then I would suggest using one of the reputable tuners on this forum. They can do a great job remotely by just exchanging logs. __________________ JRE cammed w.full bolt ons 444rwhp/422rwtq SOLD 2017 Jaguar F Type R ''Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.'' - F. Bueller

11-09-2015, 08:45 AM	#2
Hocky Drives: Cts-v2 Join Date: Apr 2013 Location: Fishers, IN Posts: 116	Your open loop stumbling is because your tune is way off with wrong AFRs and it won't run right until the fuel trims are there to "fix" it. The rpm hang is probably related to idle airflow tuning. Either way, both are major failures on the tuner's end.

11-09-2015, 08:47 AM	#3
vicnkathy Account Suspended Drives: 2014 Subaru Forester Turbo Join Date: Aug 2013 Location: NY Posts: 536	Find another tuner asap. Those are both amateur mistakes..

11-09-2015, 10:48 AM	#6
owhite3003 Z-BEAST Drives: 2013 JDP ZL-850 Track Spec ZL1, Join Date: Mar 2013 Location: Oregon City, OR Posts: 1,470	Give Tom Wong a call in Vancouver, he will dial it in for you. http://www.wongsperformance.com/index.html

11-09-2015, 11:16 AM	#8
owhite3003 Z-BEAST Drives: 2013 JDP ZL-850 Track Spec ZL1, Join Date: Mar 2013 Location: Oregon City, OR Posts: 1,470	Tom is usually spot on, my Z will stumble for a brief second when just starting out cold and I didn't use Tom. Let us know what you find out.

11-09-2015, 11:37 AM	#9
DrkPhx Drives: 2013 Triple Black ZL1 / 2006 TB SS Join Date: Feb 2011 Location: MN Posts: 2,250	I'm sure there's a cam and bigger TB in the list, but can you list your mods?

11-09-2015, 02:08 PM	#10
DrkPhx Drives: 2013 Triple Black ZL1 / 2006 TB SS Join Date: Feb 2011 Location: MN Posts: 2,250	Now that's a mod list. Well done. Assuming your cam has a wide LSA with low or negative overlap that should be relatively easy to dial in along with a 90mm TB. As mentioned above the cold start stumble is in open loop which uses the VVE table. It just takes time to dial it in because the engine temp rises so quickly on start up. The second issue is more concerning especially the surging. Since you already paid him to tune, I would bring it back with the specifics you listed here and ask him to iron it out.

11-09-2015, 02:43 PM	#11
DrkPhx Drives: 2013 Triple Black ZL1 / 2006 TB SS Join Date: Feb 2011 Location: MN Posts: 2,250	I like the specs. -5 overlap is considered mild for this motor. Those are good lobes for this application. Should have a nice and quiet valve train. The second issue could be a couple of factors depending on exactly when and where it occurs. Assuming the fueling is correct, it could be spark timing through a few tables along with the idle airflow table noted above. When you bring it back ask him to datalog while you drive the car so you can point out the problem areas. Hopefully he allows that and it will help a lot.

11-09-2015, 04:03 PM	#14
DrkPhx Drives: 2013 Triple Black ZL1 / 2006 TB SS Join Date: Feb 2011 Location: MN Posts: 2,250	^^^ Surprised there was no street tuning done with a cammed car.