my 85 gs has been stumbling at idle ever since i did the RNR a few months back. since then i have been over the vacuum leak idea a billion times, ive replaced the cap and rotor, new intake, and intake gasket, carb spacer, and niki rebuild, new fuel pump, fuel filter, fuel lines, and gas cap, 2gdfis, $100.00 msd super conductor wires, decarbonized engine, new clutch, new clutch slave, and master, 2gtranny, new brakes, u joints, new custom exaust system, and tires....WTF....why cant i get a 750 rpm prrrrrr like before the RNR, BTW i tried putting the rats nest back still the same. right now she runs rough at 1500 rpm idle but still runns super smooth at speed and cruisin. also has lots of pep smoked a stang this morn on the way home from work as a matter of fact + ive had this car to 120mph so i know it running good. what could i be missing, a sticking apex seal or something

sorry for the novel just frustrated

 

Take some detailed pictures of your carb from all angles. Meaning from the driverside, passengerside, etc.... Would like to see what you have.

 

alrighty

im on it.

 

well i took some pics but i cant get my computer to take them anymore, it keeps going to new hardware wizard. ill see what i can do to get them up

the carb is nothing more than a stripped nikki w/ mech secondaries.

 

this should be the pics

 

here are the pics

 

in the upper left pic circled in yellow is the vac line going to the advance on the dizzy in red is a check valve the i weld filled and replaced

 

Put a timming light on it to make sure the miss isn't from your spark. You seem to have covered the ignition pretty well. Just go over it and make sure everything looks good. Try some new plugs too.

Did you rebuild the nikki yourself? It sounds like it could be a slightly sticking float. I recently rebuilt my nikki and it is doing it also. When I adjusted the floats I used a pair of needle nose plyers. This works great but it can put little rough spots on the tab. This causes the spring arm to catch. Just take some sand paper and smooth them up nicely. Also look at the two guide holes that the little rod goes through to make sure they are even and that the float doesn't hit the side of the bowl.

Good luck

 

ive put new plugs 1 week ago, the floats never needed adjustment, i did go over the floats again last night before last i will check the timming right now though i acually never thought to check it ill post result

 

errr i cant get my fsm to come up, my comp is on the fritzznn. where should my timing be set leading and trailing?

 

That 1st picture with the circled broken piece is a from a SA manifold. That is the end of a early model PCV. That should be a vacuum leak right there.

 

the valve is miged closed with a new crush ring + ive pray tested it as well running with no rpm jump

 

im going to run and pick up a timing light be back soon with time spec

 

If you are stating that the idle will not go below 1500 rpm. Have you checked to make sure the throttle plate (primary side is closing all the way?)
Also you have 2 different types of vacuum leaks. One will cause the engine to idle low and will pick up rpm when you spray it with carb cleaner.
The other type will make the RPM's stay high and there is no effect when you spray it.
If you did not touch your timing before you did the RNR then the timing is not an issue.
When you check the timing. Unless you custom marked your pulley then the exisiting stock marks will show up. Being the yellow for the leading and the orange for the trailing. Meaning that there is no need to know what the timing should be degree wise because those are stationary marks.

 

OK i havent moved the timing at all and i just checked it and its spot on then.

i just cecked the throttle plates and they are closing all the way. i have the idle set to 1500 rpm, but i can adjust it down to 950-1000 rpm but any farther than that and the engine will stall. 1500 it runs a little smoother and is not so embarrassing at a stop light.

 

on a side note what is this for ?

 

According to the FSM it is a main air bleed control solenoid valve. In short it is supposed to allow air to come in from the intake manifold under certain circumstances to help with idle issues.
To further understand it access the FSM for carburetors and on page 31 it gives the description of the operation.
Since you have all emissions removed I would remove the 2 hoses at the top of the carb and put vacuum caps on them. Then wherever the other 3 hose goes cap that off also.

 

you think that this could be affecting my idle

also i saw a thread a few weeks ago about doing some rewiring after the RNR, i looked back on the write up for the RNR and they dont say anything about rewiring anything. i used the mazspeed write up. ive searched for this thread but w/ no result. is there some specific rewiring that has to be done to trick the ecu into thinking all the emissions stuff is still there?

also my adobe quit working so i cant look on my FSM at the moment

 

The emission computer should have no effect on the running of the car when all of the equipment has been removed.
To answer your question I really don't know. However it would be a easy thing to find out by capping off the mentioned things in my previous post.
I just installed the stock carb back on a fellow members SA. I left all of the rats nest off and capped off the vacuum ports on the carb spacer.
I left the emission computer hooked up with the wiring going to the various components on the carburetor.
Without any of the control solenoids there from the rats nest the carb idles and performs perfectly.

 

dang i figured the wiring the guy was doing was just to make the engine bay look alittle cleaner ill pull the valve and cap those ports tomorrow morn *crossing fingers* hope that does the trick. if not im going to tear the whole induction system apart and start over with new everything again $$$

 

Aren't the plug wires connected wrong in the last picture? The wires from the direct fire 2nd gen coil are connected to the trailing (top) plugs and the wires from the T terminals on the cap appear to be connected to the leading (lower) plugs.

 

You have removed the secondary diaphram and it doesn't look like you plugged the vacuum ports to it, there's 1 vacuum leak. If you aren't running mechanical secondarys, then they aren't working properly. If your timing is dead on, but your idle is 1500 rpm, then the timing isn't correct because the vacuum advance has kicked in at that rpm, which means the base timing is retarded.

 

^^^^^^ good catch on the spark plug wires 74RX4.

 

how do you figure there hooked up wrong....?

leading is the top right??
this is what i figured anyway becaues the motor turn clockwise and the top is the first fire that the rotor would come to hence leading---right?

i could be wrong..

 

vac advance is disconnected when doing time check, i do have mech secs and the vac port to the secs diaphram are pluged w/ JB weld