Cadillac CTS-V - My Dyno Numbers & Tune Question

Finally got the V to the dyno on friday, first pull was 418hp & 382tq, Second Pull after a few adjustments was 423hp & 380tq.

The major mods are in my signature, overall I am thrilled with the results. They came in right about where I expected them to.


So here's my Tune question, when I first took the car in it wouldn't idle at all, barley got it into the shop. With a few keystrokes on his laptop my tuner got it to idle great and not smell so bad! (apparently it was running really rich from the new injectors). Tune went great, was able to drive the car all the way home (180 mile journey) with no issues.

Then yesterday as I was exiting a freeway the car threw a code and immediately went into reduced power mode. I pulled over and let the car sit for a while and was able to start it right back up again and drive away. The code was a P1516 (Throttle Actuator Control Module Throttle Actuator Position Performance), I believe it was a result of a vacuum tube that connects to the TB falling off the passenger side valve cover.

The problem is now the car doesn't idle again, it wants to die as soon I start it. Could a reduced power mode or that code screw with the tune in anyway??

Here are Dyno Sheets:

http://i949.photobucket.com/albums/ad335/ellioth3771/07-29-2012093658PM.jpg

http://i949.photobucket.com/albums/ad335/ellioth3771/07-29-2012093449PM.jpg

I think you need to clear your codes.

I think you need to clear your codes.

Code was cleared right after it happened.

i had two ls2 tb's go bad on me..same code. one was the original and the second was a ported one..only way i fixed it was buying a brand new untouched gm tb. no issues since.

i had two ls2 tb's go bad on me..same code. one was the original and the second was a ported one..only way i fixed it was buying a brand new untouched gm tb. no issues since.

Good info, I was kind of thinking this may be the case. I think I'll just work on getting a LS2 throttle body and FAST 90 intake.

Look for vacuum leaks and re-seat the tb connector. Then pull the ecm fuse for 2 min

Look for vacuum leaks and re-seat the tb connector. Then pull the ecm fuse for 2 min

Sweet thanks for the info, I'll try this tonight.

The tune can't be lost by pulling the fuse or by the car going into reduced power mode correct? My understanding is once it's flashed you would have to replace it with new mapping to lose it.

Sweet thanks for the info, I'll try this tonight.

The tune can't be lost by pulling the fuse or by the car going into reduced power mode correct? My understanding is once it's flashed you would have to replace it with new mapping to lose it.

Tune can not be lost. Trims can be reset however. (Fuel and Idle trims)

Could you not carry the rpm to 6600? Your cutting off at 6300ish.

Nice numbers!! And like others said, try pulling that fuse or disconnecting the battery for a bit and see what happens.

Thanks fellas!!


Tune can not be lost. Trims can be reset however. (Fuel and Idle trims)

Could you not carry the rpm to 6600? Your cutting off at 6300ish.

Not sure about the rpm, I've never tried to get there myself and the guy tuning was running the car during the pulls.



Just got an e-mail back from the tuner, he told me to try an idle re-learn tonight, we'll give that a shot!

Here is Video from Last Pull:

http://www.youtube.com/watch?v=QBkSBGuSCSE&feature=youtu.be

i had two ls2 tb's go bad on me..same code. one was the original and the second was a ported one..only way i fixed it was buying a brand new untouched gm tb. no issues since.

I had to get another LS2 TB myself. My CNC ported one was also throwing REP mode and it got worse as time went on.

G/L OP. REP is a bitch.

Numbers arent bad, youll prolly see 440 with a FAST.

FAST is in the nearer future than I expected, my Throttle body is putting me into reduced power mode every time I open the car up... Damn MOD Hell...

porting the electronic tb's is not a good idea...it doesnt take much to mess up the tiny actuator

Yeah never again!! I guess you have to learn the hard way sometimes..

I had a ported TB and intake on my old setup and was throwing reduced power. I believe I had the same code as yours and borrowed 2 TB's from buddies, and didn't fix the issue. Ended up being my gas pedal went bad it was like $80 or $90. So try and borrow a TB before you buy a new TB.

Also man that graph sure is choppy who did your tune because there's still power left on the table?

This was my old setup in my ls2 before the ls3 with ported ls2 intake and TB, afr225, and pat g cam.

http://i1101.photobucket.com/albums/g431/racinking10/IMG_2818.jpg

porting the electronic tb's is not a good idea...it doesnt take much to mess up the tiny actuator

That's why you need to go to someone who knows what they're doing (or leave it alone). There are only a couple of guys in the country that have the training and experience to do it right. Shame that the Affordable Speed guy retired. The same goes for intake manifold porting.

That's why you need to go to someone who knows what they're doing (or leave it alone). There are only a couple of guys in the country that have the training and experience to do it right. Shame that the Affordable Speed guy retired. The same goes for intake manifold porting.

i had a janzer performance ported ls2 tb..lasted about a month before it shit the bed. before that was a stocker..both went bad. the problem i see with ported TB's is they for the most part are used tb's. no one offers new tb's that have been ported.

when i bought my new one i could feel the difference just pushing on the butterfly valve with my finger. my bad ones had hardly ant resistance..the new one took force to open it..i have not had a problem since and it will stay as it is.my car is finally problem free:drive:

outside of wornout tires >;-)

i had a janzer performance ported ls2 tb..lasted about a month before it shit the bed. before that was a stocker..both went bad. the problem i see with ported TB's is they for the most part are used tb's. no one offers new tb's that have been ported.

when i bought my new one i could feel the difference just pushing on the butterfly valve with my finger. my bad ones had hardly ant resistance..the new one took force to open it..i have not had a problem since and it will stay as it is.my car is finally problem free:drive:

Janzer Performance throttle bodies have a miserable track record. When I was looking for a shop to do mine, I found a whole bunch of horror stories regarding them. This is just one more to add to the pile.

The place that I went to rebuilds the entire throttle body, including the motor, before porting, polishing, and powder coating.

http://i.ebayimg.com/t/Ported-Polished-Powder-Coated-LS3-LS7-Throttle-body-/00/$(KGrHqYOKo0E33KcE(1BBO!jWsgve!~~_3.JPG

Personally i think the risk outways the rewards as far as TB porting. For the money and risk involved you MIGHT see 5-7rwhp on a heads/cam setup and no one in the world could feel that difference.

Personally i think the risk outways the rewards as far as TB porting. For the money and risk involved you MIGHT see 5-7rwhp on a heads/cam setup and no one in the world could feel that difference.

Agreed after this experience! Not worth it, the main goal for me of running the ported ls6 was just to get slightly more than 78mm. These ls6 throttle body's are incredibly restrictive, it's almost as if they stopped machining them half way through the process.

I just ordered an LS2 throttle body, harness adapter and adapter plate for my ls6 intake tonight. That will get me by until I scrounge up a little more cash for a fast 90 or 102, 90 mm will be plenty for my needs!

If this doesn't fix the issue I'll try a new gas pedal, wish I had a tech II scanner to test this stuff!!

I had a ported TB and intake on my old setup and was throwing reduced power. I believe I had the same code as yours and borrowed 2 TB's from buddies, and didn't fix the issue. Ended up being my gas pedal went bad it was like $80 or $90. So try and borrow a TB before you buy a new TB.

Also man that graph sure is choppy who did your tune because there's still power left on the table?

This was my old setup in my ls2 before the ls3 with ported ls2 intake and TB, afr225, and pat g cam.



I had it tuned at Wong's Performance which was recommended by all of the guys here on ls1tech in the Northwest section, they all rave about him. I even drove 150 miles down to go see him, he did tell me it was a "safe" tune which I was happy with. Now that you point it out, kind of makes me question if I should take the car to the local tuner here in Seattle after I get the ls2 and fast intake on.

Dont worry about that graph, its choppy because it doesnt have smoothing like most charts use. EVERY dyno chart looks similar until they change the smoothing.

If you look at Jrane's graph the upper right says SAE Smoothing 5.

Personally i think the risk outways the rewards as far as TB porting. For the money and risk involved you MIGHT see 5-7rwhp on a heads/cam setup and no one in the world could feel that difference.

But that's the thing--you absolutely do feel the different in throttle response.

I received my LS2 throttle body today, do you fellas think it is worth just polishing the rough edges of the throttle body lightly to get rid of the rough casting, no porting just a little polishing? Or should I leave it the fuck alone?

I received my LS2 throttle body today, do you fellas think it is worth just polishing the rough edges of the throttle body lightly to get rid of the rough casting, no porting just a little polishing? Or should I leave it the fuck alone?

Didn't a bad porting/polishing job get you into this conundrum in the first place?

I'll say that knocking the castings down shouldn't cause you any trouble as long as you stay away from the blade.

Leave it alone is my two cents.

Yeah I think I'm going to just leave it alone. It's interesting the LS2 has very unique angles to it which must have been engineered for a reason. Only thing that seems odd to me is the casting is so rough around the edges, is this for creating turblance on purpose or cost in production reasons? I can't imagine GM wouldn't design the manufacturing of these to make them completely smooth if it would result in better performance, seems like it would be an easy fix.

Anyways, just ramblings of a noob.

http://i949.photobucket.com/albums/ad335/ellioth3771/51d7959d.jpg

http://i949.photobucket.com/albums/ad335/ellioth3771/00e25d04.jpg

http://i949.photobucket.com/albums/ad335/ellioth3771/e760bcce.jpg

Leave it bro.. The sticker felt better than the ported when it was workin