Installed fast 90 90 setup, have a few problems now :(
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
Installed fast 90 90 setup, have a few problems now :( FIXED! lol
2001 corvette auto, stock motor with intake/full exhaust and a tune. havent had it tuned for the 90-90 yet
things i changed since the LS6 intake-
Fast 90mm intake and 90mm TB, also put my stock fuel rail with 28# injectors (used to be on my trans am) no fuel leaks anywhere
#1 The car is idling like it has a cam in it, rather rough, but when i rev it, its plenty responsive. definately more responsive than before
#2 wideband is pegged at 16.0 afr at idle. before it was at 14.7
codes- P0300 Random/multiple cyl misfire
i used the special panhead bolts on the valley cover, i torqued the intake down properly with the whole tightening/tq sequence.
i rtv'd my map sensor.
all vaccum lines are on. -HVAC, Power brake booster line, pcv line and that evap line up front.
here's a short clip of the idle. hopefully this link works. what do you all think?
2001 corvette auto, stock motor with intake/full exhaust and a tune. havent had it tuned for the 90-90 yet
things i changed since the LS6 intake-
Fast 90mm intake and 90mm TB, also put my stock fuel rail with 28# injectors (used to be on my trans am) no fuel leaks anywhere
#1 The car is idling like it has a cam in it, rather rough, but when i rev it, its plenty responsive. definately more responsive than before
#2 wideband is pegged at 16.0 afr at idle. before it was at 14.7
codes- P0300 Random/multiple cyl misfire
i used the special panhead bolts on the valley cover, i torqued the intake down properly with the whole tightening/tq sequence.
i rtv'd my map sensor.
all vaccum lines are on. -HVAC, Power brake booster line, pcv line and that evap line up front.
here's a short clip of the idle. hopefully this link works. what do you all think?
Last edited by 98TADRIVER; Jan 4, 2011 at 12:03 PM.
I have had that issue with using injectors that have been sitting awhile. They need to be cleaned. Since it runs you might get buy with going and getting a bottle of Chevron Techron injector cleaner and put it in the tank and drive around. On some I have taken the injector rail off and pressureized the rail with cleaner and had to tap on each injector with a screw driver handle to make them spray. I have a Snap-on injector testor to individually fire each injector. Almost a must if the injectors are that dirty. Try the cleaner in the tank first. I have cured them from that before.
This might sound odd, but did you use the FAST stainless allen-headed intake bolts instead of the stock hex intake bolts? I initially used the stainless allen bolts, but developed a vacuum leak. Chased it down and couldn't find the culprit, but a friend suggested switching back to the stock intake bolts.
I did, and problem solved. Obviously the above doesn't apply if you used the stock intake bolts to begin with...
I did, and problem solved. Obviously the above doesn't apply if you used the stock intake bolts to begin with...
check your coil wiring. I have had the same problem before and the coil wire connector was the issue. sometimes after being removed and plugged back in the wires dont all make a good connection
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
thanks for all the input fellas, i greatly appreciate all of it. Ill go over everything again tomorrow. i need to get some carb/tb cleaner, im all out. And theres a blizzard going on up here in nj, so im not sure when ill be driving in it for a can of that stuff lol
Squirts11- im using the stock intake manifold bolts. tightened them in sequence and torqued them to 44in lbs first pass, then 89in lbs on the final pass. i
Squirts11- im using the stock intake manifold bolts. tightened them in sequence and torqued them to 44in lbs first pass, then 89in lbs on the final pass. i
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
In closed loop shouldn't the computer be pulling fuel out to maintain 14.7:1 despite the injectors being larger and the computer no knowing it. If anything I could see it running rich not lean.
I could see it go either way.
x2 on the vacuum leak, I think that's why it's at 16:1
I could see it go either way.
x2 on the vacuum leak, I think that's why it's at 16:1
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
figured it out today 
sprayed some carb cleaner where i thought the problem might be.
change in idle was noticeable.
apparently, rtv gasket maker isnt a good substitute for the O ring gasket.. i went down the street to the local machine shop and lucky me, he had exactly what i needed! put it back together, fired her up and what do ya know, smooth idle and runs even better!! thanks for all the troubleshooting help fellas! No retune yet. however, driveability is fine and the afr is at 14.7-15.0@ part throttle and cruise, and 12.6-12.7:1 @ WOT. Should have it re tuned on sunday
sprayed some carb cleaner where i thought the problem might be.change in idle was noticeable.
apparently, rtv gasket maker isnt a good substitute for the O ring gasket.. i went down the street to the local machine shop and lucky me, he had exactly what i needed! put it back together, fired her up and what do ya know, smooth idle and runs even better!!
thanks for all the troubleshooting help fellas! No retune yet. however, driveability is fine and the afr is at 14.7-15.0@ part throttle and cruise, and 12.6-12.7:1 @ WOT. Should have it re tuned on sunday 
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
I RTV'd it between the intake manifold and TB. I wouldnt recommend it, as the seal was not good enough. The the new gasket i used looked like a regular rubber O-ring and works great
Lol.. uhh ya dude.. you should have posted that info in ur beginning post lol.. glad its fixed tho now go enjoy it!
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
Thread Starter
Joined: May 2005
Posts: 1,449
Likes: 0
From: South Jerzy
Me 2!! lol
i was told that the TB is a nickwilliams ported, and the intake manifold is unported.
cant wait til' theres a track rental or the new season begins. whichever comes first lol
I'm considering doing a FAST swap on mine, it would be good to know if it was worth it.. lol