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Okay so i just got my car running less than a week ago. I got plates and insurance on it on Friday and today has been my 1st day off work and school so i worked on my car all day (1983 gsl 12a)
It wouldn't start before i rebuilt the carb (it flooded hard) after the carb had been rebuilt its been okay starting and it runs but this hesitation is getting to me. My parents want me to get it fixed before they let me drive it all the time soo can anyone help =)).
When i hit the gas its rpm's go down and seems like its gonna die then it picks up and runs normal.
What ive done to it so far
put a new inline fuel filter in
new air filter
new spark plugs (densos yeh i kno i wanted ngk's but they were out)
new wire set
new battery terminals
i have seafoam for once i start driving it to clean it also.
What do i need to do.. my dad thinks its either timing or the air fuel mixture is off.
I have searched and searched and couldent find anything please anyone.
Just to be clear, the carb will draw fuel in when it's running, and you could be seeing that. I'd recommend pulling the plugs, turning the car to 'run', and pulling the throttle cable while looking down the primary barrels. Without the engine running, you should see the Accelerator Pump shooting fuel into the carb. Once you're done, turn the engine over a few times, put your plugs back in along with the wires, and crank her back up.
The only reason to pull the plugs is to avoid flooding. There's a good chance you'll flood it while playing with the AP, and it's a lot easier to restart if you'd already removed your plugs and they're still dry.
The AP is the likely culprit. Another possibility is that the car has mechanical secondaries (not stock, but a common mod) which you're not used to, and it'll make the car bog if you drop the throttle too quick. While you're checking the Accelerator Pump again, also pay attention to the two larger bores. If you slowly turn the primary throttle linkage (or pull the cable) and the secondaries (larger bores) open smoothly with the primaries, then you have manual secondaries. Let us know what you find.
77 PA236 : 4-port 13B, 51 IDA
okay so i just checked it. I had the car off but they key to run when wee p[ushed the gas it shot a little bit in then nothing more. so is it the ap?? and if it is how do i fix it?? do i have to replace it or what?
thanks for the feedback guys
Okay soo i have a bit of a update to see if u guys can help me. We checked the accel pump and i still dont know if its working correctly or not (we tightened the screw down under it a bit to see and it didnt change much.. idk if i did somethign wrong please tell me). Me and my dad changed the idle screw and the air fuel mixture screw. Right now the car idles between 12-1400 wich is about double what i wanted it but it wont go down much more.. we had it at 1000 at ont point. After messing with the afm and the idle the hesitation isnt as bad.. still bad tho.
starting at 1500rpm's is almost fine... with little hesitation. if i start it at 1700-2000 rpms it almost dies... its like a complete dead spot. and when ur driving and shifting it ont he road it bucks the car every time u shut cuz of the hesitation around that rpm. we can drive it at higher rpms fine and just shift at 2500+ but i still want to get this fixed..
Bump, I'm having the same issue! There's a dead spot right at 1700 RPM. I don't hit it when revving very lightly, but it cuts in the same spot every time I take off below 1700. So how is the accel pump adjusted?
If your idle's that high, then you have a vacuum leak. Since the engine now draws in more air than normal, you've also adjusted your idle to be super rich. That way, what little bit of air DOES come in through the carb, it has to mix with an extra-rich mixture in order to get it to run once you add in the air from your leak.
You should be able to spray starting fluid or brake cleaner on your manifold gaskets and ports (including everything that gets a vacuum line), which will temporarily clog any air leaks. If the idle changes for just a moment, before the fluid evaporates, then you've found your leak.
Once you have your idle down to a semi-steady 600, you can bump it up to a rock-solid 800 or so and deal with the AP. You'll also lean your idle mixture back in the meantime, and your throttle response should improve a little.
You can use Mazda gaskets, RTV, or gasket dressing (I swear by hylomar) to resolve the vacuum leak once it's located. Just be patient, and check everything.
77 PA236 : 4-port 13B, 51 IDA
If you can have a vacum guage it will help a lot to diagnose your problem.I think for a rotary it should read about 15.These are pretty cheap at the auto parts store.All you have to do its to conect to a vacum source.
83 rx7 bogs out going up hills n when throttle is pressed fast.... hesitation
I'm having the same problem. 83 limited edition rx7, k&n airfilter n rb headers only mods. If I hit the gas at all fast, It drops rpm n almost bogs out, and when I'm driving up a long hill, after about half way my car starts bogging out to the point where I have to pull over for a second then its fine when I pull off. I've put new ngk plugs n wires, k&n airfilter, seafoamed it. I do know that there is no intake manifold gasket but I just ordered it n have it and also have a nikki carb rebuild kit I just got. I got mine running at about 750 rpm since I've kinda tuned it. I have no timing light to time it or understand how, n I dnt have a oxygen sensor to see what my exhaust is putting out to tune the gas mixture. Its tuned as good as I can get it. I dnt think my carb is the problem although I am rebuilding that n I'm putting a intake manifold gasket on. But why would my car drive steady up a hill then just start bogging out, I down shift, bogs out, down shift to first bogs...... sit for 15 seconds n I can drive.....?