Well we're back. On this car we've checked the vacume hoses, we've replaced plugs, wires, cap, rotor, fuel filter, pcv valve, CHTS, and we have no check engine light we've still got a very stumbley idle and I REALIZEd the throttle cable was tight to the point where the car is always getting SOME throttle. if it doesnt get throttle it stalls. if I adjust the cable so its tight but not opening the throttle, the car will stal immidiatly on startup unless I rev it and keep it running. after it warms up a little its slightly better but still idles low and shitty and stalls out.

What else will control idle and cause an issue like this on a 1984 N/A Z31? I would just like to get this thing running smoothly if at all possible :-D. As much as I like randomly tooling on it... it would be good to get the idle problem solved and move onto other things. Anyone got any suggestions here? Please something anything?

OH ALSO it has a 240sx throttle body on it apparently, there is a plug coming off that therottle body and another one near it, entiher of them is hooked up, for the hell of it I pushed the one that would fit onto the throttle body onto it, with no affect. Anyone have anything on this? Should I go back to stock on that?

Charles

 

What rpm will the car idle at if you manually move the throttle? There are 2 adjusting screws on the FICD. This is located just in front of the throttle body on the side of the intake. You will only adjust the screw closest to the throttle body. This will move the idle speed up and down depending on which way you turn it. Do not adjust the screw in the front.
If you have a manual you have probably already tried it but I figured I would throw it out there.

 

with throttle on, it will idle with even a little bit of gas but its VERY rough and choppy and uneven. more of what you'd expect from a cammed muscle car or something than from a car. It stumbles and such... it'll idle at even like 800 but you need to set the throttle like I said,.. no throttle = the car dies.

 

you have either an injector problem or a vac leak, the 240 TB has only one vac port from my knowledge, whilst thez31 tb has 2, from memory you need to use a tee piece to connect them up. my car has the same problem and 2 days ago an injector died.

 

So we should probbaly just replace all injectors, and associated harnesses next? Any chance it could be like the fuel pressure regulator or anything? I will also check the vacume situation out and see what we can figure. Going to look over the vaccume system real thoroughly. Maybe get some starting fluid and spray around a bit.

Charles

 

Sometimes, using the crappy tuning parts sold by AZ or AA or PB cause the engine to run worse than before the tuning was done. It is highly recommended that gin-u-wine Nissan cap and rotor be used.

Based on your description of the symptoms, and the timing (immediately after tuning), the probability of a vacuum leak would also be highly suspect. It's almost impossible to complete a tune up on one of these VGs without disturbing other elements. Also, look for an electrical connector you may have pulled loose during the process.

Look for the simple, easy stuff before jumping to the more obscure, complex, and difficult items that may (or may not) have failed.

 

don't replace whats not broken, simply test them. take your injector connector off and test the injector harness with an ohm test or condenuity test, if you get a reading it means its all good. then put the multimeter on your injector plug terminals and see if you get the same thing. if all is good there your injectors are most likely fine. next run the engine and disconnet a spark plug lead on one cylinder, then shut the engine off reconnect the plug, start the engine again and pull the next plug, if you pull a plug and the car doesn't sound any worse, then thats your troublesome cylinder. Check the idle control valve and turn the adjust screw out or in and see how that goes, since its an adjustment and the design of the plenum, one cylinder may be getting more air than the others.

hope this helps

 

Why does no one end these thread?!?!

A. This fixed my car
B. This did not fix my car

It's not brain surgery people!!! Help each other out!!!

 

Original poster has not logged in for 7.5 years... I think a rain dance would get you an answer sooner than the OP. Thread closed.