barrok69

So I'm now looking for my 3rd LS6 throttlebody.... Anybody have any ideas what could possibly be killing my throttlebodies? Stock one went at 25k miles. Second oem replacement went at 18k miles. Right now the car is basically dead until I put another TB on it so I'm looking at options.

It is currently throwing P0120, P0220, P1516, P2101. It threw these codes the last time and replacing the TB resolved it for 18,000miles up until now.

Any ideas?? Maggie related? I do "exercise" the throttle quite a bit.

Thanks.

DMM

What is the voltage drop to ground? You can try to run a ground strap to the TB bolt and that may help.

Going through that many throttle body's is odd unless you keep trying used ones.

barrok69

Voltage is 12.12V on the motor side, which is exactly what my battery is at right now.

on the TPS side i have 4.97V and 4.3V to ground.

GFallen

I was having issues that turned out to be the connection plug at the throttle body. I bought a new harness and that fixed it, after I replaced the throttle body, gas pedal and checked all the connections...

88BlackZ-51

Have others had this issue?

Naf

iTrader: (1)

plz post your C0803 and C0805.

If they are too low, your cpu will think your car is a run away and go into limp mode.

Also i will need to know your MAX g/s on the maf during your dyno runs...

Brackets

I had all of those codes. I replaced every part of the drive by wire system (let me know if you need a throttle position sensor, throttle control module, or a gas pedal lol)after thoroughly checking all of the wiring including grounds. I even broke down and, wait for it....................took it to the dealership. Then i took it to a retired gm mechanic. In the end i found that some water had gotten past my ecm connector and corroded about 9 of the contact pins. To make things even more interesting either the dealership tech or the retired mechanic had reversed two of the throttle body wires in its connector but I'm now certain that the original problem was the ecm connector. So if you haven't already checked there I'd have a look at that, its an easy one and i was pissed at myself for taking so long to get there. Your situation is a little different than mine in that you seem to be okay after changing TBs (that didn't help me) but you never know, and like i said the ecm is easy to check. Good luck, i know it can be frustrating.

barrok69

I don't have that data unfortunately. Dr. Phil tuned my car and I have great confidence that he didn't mess up anything in the tune as the car was running great for almost a year. He completely retuned the vehicle from when I got it, and with my old ECM I had the TB fail on me.

Thanks, I read through your thread, it was a pretty interesting ride. lol.

It seems my TPS may be suspect. I have a new one on order to see if that will fix it. I put my old intermittent throttlebody TPS sensor in the car and it started up good then went back into limp mode like it normally did back when I had that TB in a year+ ago so that is a good indicator it might just be the TPS sensor that is going bad, not the rest of the TB.

Darkman over on the other board suggested adding some extra grounds from head to head and body to heads. It never hurts to have extra grounding. I'll add that to the "to-do" list.

If the TPS sensor doesn't resolve it I'm going to buy a new 90mm TB and go that route instead of buying a new LS6 TB.

serik21

Just go with the 90 and call.it a day.

barrok69

Has anybody ran a Nick Williams 102 or FAST102 TB with a maggie setup ? I'm most likely doing heads/cam and some porting down the road, so why not go big??

Any reasons why I shouldn't go 102?

Naf

iTrader: (1)

I run it on my NA, but i would strongly advise to get the 90mm. You dont have any heavy mods to require the larger tb...

its a 112, my buddy here is running a 90 on his 2300 with no issues...

Vcaddy71

iTrader: (2)

Any reason not to run the FAST 92 as opposed to the 90mm?

Naf

iTrader: (1)

The GM 90mm is proven and can be adapted to fit, last i checked all the FAST TBs are cable, and not fly by wire

barrok69

So I determined that the LS6 TB's were toast due to deformed springs internally, so nothing to really salvage. The 90mm are supposed to have beefier return springs so this should help with my situation.

So I got all my parts together: 90mm LS2 TB from rockauto, 90mm Maggie snout and Caspers conversion harness and 4x longer M6x45mm-1.00 pitch bolts. The 90mm snout is a bit thicker than the 78mm snout.

Thanks to Ronr from caddiforums for having an unused 90mm snout and harness just waiting for me to buy

I was able to clean up some of the maggie hose hell by getting rid of the TPS extension harness and T'ing in the passenger side PCV line to the driver side snout vac line as there is no provision on the 90mm TB for that hose. I wasn't in the mood to cut a hole in the intake at this point. I cleaned up most of the vac line routing and made sure nothing was going to be rubbing on the jack shaft with some zip ties to keep everything secure.

Another thing I did was eliminate the line that was used to the throttlebody heater on the LS6 TB. Since the 90mm TB doesn't have that (nor was I going to keep it if it did) I just plumbed from the block valley across to under the radiator cover and back to the factory T without having to modify the lines very much.

There is no gasket between the snout and the supercharger housing. Maggie suggested I use loctite 510 to form a seal between the two. That stuff is expensive but works great.

My Bypass valve was also hooked up to a small sensor looking thing on the firewall that has a wire going to the magnavolt. It also had a vac line going from the 78mm snout back to the sensor, and another vac line going to the bypass valve. My tuner and I found that whatever that thing is was actually preventing the bypass to open at idle causing the supercharger to make some excellent rock crushing noise. pushing the bypass valve manually made the noise go away. So when I started re-routing things for the 90mm conversion I eliminated that "sensor thing" and just put a direct vac line from the bypass to the snout. Idles good and sounds normal now. Since I did this though I definitely need to get it re-tuned as it surges off throttle then eventually stabilizes. minor stuff, but overall great success.

Next step is to delete the maggie fuel return loop hose and plug the stock fuel line into the opposite side of fuel manifold (needs to be drilled out) and plug other end with an oring'd fitting.

Before



Some pics of the new 90mm vs. old 78mm parts. Quite a huge difference between the two parts.



After

Naf

iTrader: (1)

Next mod aught to be relocate the batt to the trunk...

barrok69

I don't really see a need to do that at this point. It's happy where it is

88BlackZ-51

Will you be putting it on the dyno? I am curious what gains if any from the TB?

barrok69

It needs the tune cleaned up a bit now, so I'll have the tuner go through the whole tune to make sure everything is looking good. I might as well Dyno it to see what gains are to be made. I'm really just excited to have the car back up and running now.

barrok69

So in my rush to clean up the vac lines I mistakenly Tee'd the two PCV lines into the vac port on the driver side of the Snout....Whoops. This resulted in a fantastic oily smoke show from the tail pipes. lol.

I fixed it by buying a 3/8" Heater hose fitting with 1/4" NPT thread , cutting down the length of the PCV hose and drilled a hole into the Maggie intake tube. All is well now!

Haven't taken it to tuner yet so idle is still a bit bouncy. Hopefully after the holiday weekend he'll be able to get me in.

raven154

iTrader: (14)

That's odd. I have my PCV hooked up like you had. Both valve covers tied to the vacuum port and have no issues with oil. It does need a catch can but its nothing abnormal.