I was checking the vac lines and links on my carb ('84 Z28, L69, q-jet), and I noticed that there are a lot of lines that are either missing, and/or plugged with screws, etc. I've had my car for almost 2 years now, but I want to know where I could find a diagram of all the vac lines and where they go to, because I belive I'm running extra lean, there's pinging at half-full throttle and the rpm's have risen about 200. Any help is greatly appreciated. The only code on the ECM is 32.

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'84 Z28 L69, Edelbrock performer intake, stock q-jet

 

At one time, there was a decal under your hood that showed the routing of the vacuum lines. Look again and see if it's still there.

If not, a new decal might be available from the dealer - check it out. If not, then I don't know of any reliable source except the factory repair manual for your year, or somebody's car that does have the sticker (mine's an '86 LG4, so probably won't be exactly the same).

Your code 32 is probably saying your EGR valve isn't working correctly, or your barometric pressure sensor isn't working. If a bunch of vacuum lines have been capped off, that isn't too surprising.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam and intake, World 305 heads, Hooker headers & y-pipe, 3" Catco cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" Hedders, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere w/open diff & slipping tranny. Daily driver while Camaro was being put together.

 

Okay, thanks for the advice. I went ahead and checked the timing, which was way advanced, so I set it roughly to 4* (There aren't degree markings on the timing marker) and raised the idle accordingly. That stoped the pinging, but the idle varies rpm's now, and I have lost a ton of throttle response and torque. I can't even squeal the tires when I floor it from a stop now. I'm going to get the vac line diagram so hopefully that will help, but I'm confused as to what to do with the carb now.

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'84 Z28 L69, Edelbrock performer intake, stock q-jet

 

Having re-lined a few CCCS cars and NEVER having seen a vacuum diagram for any of them, this is cake. This is all you need to hook up, any left-over ports are capped. There may be some minor difference, but you should be able to figure out how to handle it if you have any mechanical ability.

#1 EGR solenoid - from the factory this usually is sourced from ported vacuum on the front pass. side of the carb, about halfway up the body. It should have a neat plastic hose running to it. Sometimes this may come from a TVS (thermostatic vacuum switch) on the front of the intake, and the TVS gets it's vacuum from teh aforementioned spot. If this is the case, screw that TVS and run the vacuum straight to the solenoid, and from the solenoid to the valve. The computer won't try to use EGR when the engine is cold anyway, so you've just eliminated junk.

#2 EECS (charcoal canister) - This one is a little tougher, cuz it has been different in every car i've looked at. The basics are the same though. I'll just describe this the best i can and you'll have to look at it for a bit to get it straight for your car.
Start by looking at the PCV valve. Follow the hose off that to the carb base. It will probably have T in it, but there might be a seperate big port on the base that has another similarly large hose coming off it around there. This is what we are looking for. This big hose then runs to the dumb looking valve thing sitting on your thermostat housing or thereabouts. The big dumb looking valve should be labeled as far as which connections are which. Also hooked to this valve will be another large hose, which will run to a TVS on the front of the intake. The other side of this TVS runs to the canister. Oops, i lied, there is yet another big port on that dumb looking valve that will run to the big port coming off the top of the carb, kinda on an angle, this is the carb fuel bowl vent. The last port on the valve is a little one, which goes to a ported vacuum on the front driver's side of the carb. Also, some cars have another little valve, either inline with the big hose coming from the canister, or in the canister itself, which IIRC i hook to full manifold vacuum.

These are the biggies that get the bad wrap. All associated vacuum lines for the EFE system (heat rise flapper in the exhaust) should be discarded. Also, i really don't recall the routing for the AIR vacuum switches, but if you really need them to work i am reasonabaly sure they get full manifold vacuum.

The only other vauum lines are the little one that runs straight out the back which goes to the VAC sensor on the driver's side firewall. Also, theres the brake booster (big metal line) and the hose that comes off teh intake behind the carb that runs to the climate control system.
...ed

 

My '84 L69 is just like yours, no bottom, you'll get most of your power mid to top. The 6* mark is right in the center of the timing plate. If it's bogging on the bottom end, check out Ed's tech article on the CC carb, helped mine some.
When you get your engine in order and if it still won't launch from a dead stop very well, you could consider a higher-stall torque converter, that'll get you going.



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DR Stevens
1984 Trans Am 305HO L69
sucks gas, hauls ***
1991 Firebird 305 LO3
for days when I need a/c