Secondary Air Valve Issues 83 T-Type

[nothingman]

So I've been becoming increasingly frustrated with this carb that I rebuilt... The choke hasn't been opening completely and then after running for a good 30mins it will shut sometimes killing the car. I've already swapped another electronic choke coil in and same result so I'm thinking there is an electronic issue in the wiring. So I have temporarily propped the choke open and that solved it, which has me thinking about removing the choke all together. Not to mention I've read in both of my rochester service manuals that folks remove it sometimes.

Well anyway that isn't my main concern but I'm not sure if it has anything to do with the secondary air valve malfunction. My main concern is the secondary air valve butterflies do not seem to be opening??? BTW I've got the the secondary butterfly stop lever held back so they are free to open. What happens is when i'm accelerating I hear the turbo start to spool and the boost gauge approaches 0 then as it heads to 5 psi when i feel like i should have some pickup... I get nothing but a cloud of unburnt fuel puffing out the tail-pipe and a motor that feels and sounds like it wants to get up and go but is being restricted??? I've swapped the front vacuum break for one that held vacuum but still same issue. i'm convinced the air valve is not opening but since i can't see under the hood when i'm driving i'm not 100% sure. Has anyone experienced the same issue or know how to test for my problem? Should the air valve open when i rev the car in park, because it isn't? Any help would be much appreciated because it has seriously been driving me nuts haha. thanks!

 

[b4black]

If the air valve didn't open, then the rods would not be lifted up out of the jets - there would be very little fuel flow. The air valve will not open reving in park.

Maybe your air valve is opening, but the secodnaries are way too rich. Are you running the stock rods and hanger?

 

[nothingman]

Oh yea didn't think about that whoops. I'm pretty sure they are the same stock rods, although I do have two 83 t-type stock quadrajet e4m carbs and when i did the rebuild i took the best parts from both... I'll pull the rods from the spare and compare the markings to the rods i'm using.

could there be another explanation?
i'm also having trouble finding the timing specs for the stock car, could that be an issue?
i don't think this has anything to do with it; but i did replace the idle tubes with a pair that i ordered from cliff ruggles and the inner diameter did seem larger.
would you recommenced removing the choke?

thanks in advance i'm still really new to turbo and electronically controlled carbs, double whammy i guess haha. any info is much appreciated

 

[b4black]

I believe timing is 15° BTDC with the electrical connector disconnected. It should be listed in the emissions stocker on the fan shroud.
I wouldn't think the idle tubes would effect the secondary A/F metering.

I believe the stock rods aree stamped DD. They are thick, but I find that I am running very rich at WOT - about 11:1 on the wideband O2 sensor. I haven't changed anything on the carb accept for bending the tab that allows the air valve to open fully.

I have never had an issue with the choke. I would fix it vs. removing it.

 

[nothingman]

you're right, there it was on the shroud haha deem so 15 btdc is that for the turbo so there i won't have any detonation... most the other cars which were na it wad far more advanced in timing... just curious being new to forced induction n all.

happened across a reman elec quadjrajet for only 100 so i picked it up n put out on... runs and idles better even got the secondary air valve opening while i rev it in park but the choke it's still giving me issue n i can't drive it, must not be giving it enough gas because it won't even get the car up a slight incline lol... I'll prob have to run the numbers to see what the carb came off... would it be easier to change the main jets on my new carb than to trouble shoot my old carb for the secondary issue?

 

[b4black]

There are no main jets to change on the electronic quadrajet. The primary fuel mixture is controlled by the computer. There is an idle air control valve adjustment under one of the tamper proof covers. Before messing with that, I would look for vacuum leaks and make sure the oxygen sensor is fresh. Lazy O2 sensors will cuase idle issues. Do you have a scan tool?

 

[Freddie's Buick]

I'd forget the secondaries for now. I'd worry about getting that carb working right. There's a 10 amp fuse on the fusebox for early Regals, (81-84), it clearly shows CHOKE. Check that fuse first for your choke issue. If the fuse is ok than use a testlight on the wire that attaches to the choke when the ignition switch is on. It should show some current. If not you have an electrical issue also. Rebuilding a Q-Jet is not like rebuilding a Holley or Carter, (those carbs are made for tunners that can't handle complex plumbing). If you don't know how the carb works farm it out. Cliff Ruggles can deal quite easily with any Q-Jet. No sense in ruinning the engine with a bad carb. Q-Jets are not DIY friendly, you really have to know how they work thoroughly before messing around with them.

 

[b4black]

Good book:
http://www.amazon.com/Rochester-Carburetors-Doug-Roe/dp/0895863014


I haven't seen this before: :
http://www.amazon.com/Rebuild-Modify-Rochester-Quadrajet-Carburetors/dp/1932494189

 

[charlief1]

There are no main jets to change on the electronic quadrajet. The primary fuel mixture is controlled by the computer.

To a point Rich. You can modify the seats and change the dwell with the solenoid to increase fuel some and can even drill the seats out slightly, but the puter will correct for the fuel mixture so it's at the best ratio.

 

[Freddie's Buick]

I haven't seen this before:

http://www.amazon.com/Rebuild-Modify-Rochester-Quadrajet-Carburetors/dp/1932494189

IMO no way near as good as the Roe book, (I have both). But it's a great addition. I consider myself well doctored due to having the Roe book. The Ruggles book is mainly tuning for big block engines, (Pontiac's and Chev's), modifying and repairs. While the Roe book actually teaches one how they work.

 

[Freddie's Buick]

To a point Rich. You can modify the seats and change the dwell with the solenoid to increase fuel some and can even drill the seats out slightly, but the puter will correct for the fuel mixture so it's at the best ratio.

From my experiance if you drill anything on the primaries of a CCC carb and you will ruin it. Yes the ECM is programed for 14.7 but limited to correcting OEM on the Q-Jet's primaries. As far as I know Dwell is not adjustable. You will burn fuel like a gas whore. There are some slight differance on the primary metering rods from one car to another. The only thing one can do on a CCC Q-jet is on the secondaries.

 

[nothingman]

thanks for the advice folks, i'll check the O2 sensor and the choke fuse. but i think i will put the original carb that i rebuilt back on. the pepboy remaned carb i bought that is on it now is from a NA 307(i guess, googled the carb number) i've heard the throttle linkage and base plate are different than the turbo carb. the carb that i rebuilt drove and idled fine on the car the whole issue was when i tried to accelerate quickly the turbo would wind up but the car would just bog and blow smoke out the pipe... unburnt fuel, which carboned up my spark plugs and possibly the O2 sensor? Just confused about why the secondary air valve butterflies were prob not opening... here is a video of the original carb i rebuilt on the car idling...