themack56

iTrader: (70)

ok this weekend i installed my fast intake and 90 mm wilson tb, i also went ahead and did the ls6 pcv conversion on my 98 z28, well i had everyhing hooked up and i go and turn on the car and it turns on but it shuts off immediately, at first i thought it was the maf not reading the air, but then i disconect the maf and the air sensor in the lid and i turn car and it stays on but at 3000 rpms, i leave the car like this and i go look at the engine and i hear the tb sucking up alot of air, its closed but its a little open cause it dosnt have the little hole as the stock tbs, well i put my hand near the tb and its sucking up alot of air, i put my hands around the intake ports around the heads and i dont hear nor feel a vac leak, the sensor in the rear of the car is connected the to vacs to the manifold are connected, i dont see whats the prob, plz help guys

y2k_ta

iTrader: (80)

Did you check the oil pressure sending unit on the driver's side rear of the engine for damage?

Was the plug for the Cam Position Sensor accidentally disconnected? (it's at the back of the engine)

Check to make sure you've hooked up the IAC and TPS sensors.

Did you put a gasket in between the tb and intake?

themack56

iTrader: (70)

i havent checked the oil pressure sensor, im not sure on teh cam positioning sensor, iac and tps are connected, and there is gasket between the manifold and the tb, so u think it might be the sensors in the back?

themack56

iTrader: (70)

anyone?

y2k_ta

iTrader: (80)

You might also want to check the vacuum hose at the passenger-side rear of the intake. It could have come disconnected during the install.

lastcall190

iTrader: (36)

Might be a stupid suggestion, but brake booster hose, check that. Mine did the same thing when I did the LS6 intake install and I was pissed... took 5 seconds to attach and fired/ran perfect Good luck.

-J

matt94z

iTrader: (49)

Is your map sensor hooked up and in the intake? It could have came loose from the intake.... Did you change valley cover bolts also?

themack56

iTrader: (70)

valley cover bolts were changed, ok i pissed so i just took the car to the mechanic, before i did that this is what i did, since the car wouldnt turn stay on, i tried to put the bellow on the maf and the tb, and guess what it stayed, but the problem now was that the at idle it sometimes it would go up and down little bit, so im thinking vac leak, i check and i hear no leak or anything, so i finaly just took the car to the mechanic , he said the maf is dead and the tps sensor has to high of a voltage so that needs to be replaced, that would explain the idle being up and down, i drove the car to work but when i went all the way up to 4000 rpm i would hear the clicking noise so i told my mechanic to check that to, and guess what it was something in the starter or something so that had to be replaced, im pissed cause the maf and tps worked good on the ls1intake, i think its because i didnt disconnect the battery when i was unplugging sensors lol,im an idiot for not doing that, i asked him if the manifold was sealed properly and he said yes

DirtyJohn

iTrader: (8)

Your TPS will likely be out of range if you haven't adjusted it to get it within the sweet spot (which is .5V <= X <= .69V fully closed if I'm not mistaken). If the mechanic is just pulling codes and seeing an out of range code, its prob not bad just needs adjustment. You can test it with a multimeter, look up the bumpstop mod to get the proper specs on voltage and info on how to do read it from the TPS.

I'm also no expert here, but it has taken me a while to get my idle solid with my 90/90.
I know its not a huge change from the LS6, but a tune might be in order.

DirtyJohn

iTrader: (8)

I'm feelin saucy so give this a try if you like, its free, easy and won't make it run any worse.

1. Start with car off keys out
2. Find the adjust screw on the TB and turn it one full turn counter clockwise. (this should be the direction to CLOSE the blade, but if it isn't for whatever TB you have, turn it the direction that closes it)
3. Adjust Throttle cable if need be to appropriate taught-ness.
4. Pull TPS wire connector out of TPS
5. Turn key to on position but DO NOT CRANK AND START, let it sit until its done "ding" ing the 5 times it dings.
6. Car off keys out
7. Replace TPS wire connector to TPS
8. You can try starting it now and see if it behaves better.

If I am right, and this is what's going on, after this try it will either improve some but not perfect, or totally choke. If its improving and your 3000 RPM drops but not all the way, repeat the procedure. If it totally chokes it and it dies right away, repeat, only reverse the set screw a fraction.

Your basically letting the computer relearn the TPS 0% with a new, hopefully closer to correct Voltage value by doing this.

I think and I could be totally wrong, is your TB was set open way too far, and jacking up your RPM. Getting your idle back to sanity isn't going to be as easy as this fix, but from what you described, something sounded terribly wrong, but not broken to me.
Granted I'm kind of new to this, but I did do my 90/90 and TPS voltage is def an issue, especially if the set screw was unknown from the factory, or wiggled out of range in shipping/handling whatever.

Also, am I the only one that thinks airflow will def be out of wack with this, affecting idle and MAF operation?

I did my 90/90 before I did the cam, but I can't remember if I had this many woes with idle or not.

If for whatever reason you feel like the car is running worse after doing what I said, you can just repeat it, only turning the set screw back to where it was depending on how many times your turned it. Using a multimeter or scanning software to get the TPS voltage in the proper range is ideal though.

themack56

iTrader: (70)

thnx for ur help, im picking up car in the morning, hopefully, the mechanic tested the maf, and it wasnt getting any voltage or something like that, he said the reason my idles were off was because of that, ill let him do his thing, but he better fix this if hes making me buy stuff lol

jmill96Z

iTrader: (3)

I hope you don't get it home and find a big hole in that new TB.

That TPS relearn trick is good ****. It settled my idle down big time. Car used to have about a 1K fluctuation, now I've got it down to about 100. Good enough for the girls I go with.

themack56

iTrader: (70)

ok. i got my car back and, guess what, i still hear a noise when i hit 4500 rpm, like a rack rack rack sound, i went back to the mechanic and he got in the car with me and he hurd it, so now he says that he will not charge me any labor until he fixes the prob, he said it might be coming from my left valve