4A-C help

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BlackStar
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4A-C help

Post by BlackStar »

These are reposted from another site, bear in mind.

I actually got a rebuilt and adjusted carb on a parts trade(i traded a lot of my 4ag stuff) My question is, how long does it fast idle? I ask because I'm unfamiliar with the carb, My old one was completely out of tune, and in need of a major overhaul, so I have no prior knowledge. I am wanting to see/read what is normal operation, and what isn't. being prepared pretty much.

which leads too

I got another 4ac AE86 question, related to the one i posted earlier. I ran the car, but it never came back down from fast idle, in fact, it climbed 1000 rpms higher then it should have been. Even flooring the car to get the fast idle to disengage didint help, the car actual stuttered. The higher it revved, the less effect the accelerator hadThe car was completely warm at this time. any thoughts or solutions?

and also

I haven't adjusted anything. I got another TVSV sensor, since the one on my car was broken and i jerry-rigged it together, that could be causing my car to stay so high and not rev down. I'm also going to back off the fast idle screw to see how it runs. Jut takes 1 or2 tries to get it to start.



besides hissing and spitting at the car, I haven't tried anything, I'm not sure were to start. I want to do the TVSV switch, but what else should i do?

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Re: 4A-C help

Post by dr.occa »

Is this with a stock/factory carb or an after market carb like a Weber 32/36 or equivalent?

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BlackStar
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Re: 4A-C help

Post by BlackStar »

nope, completely stock carb with all of the part on it.

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Re: 4A-C help

Post by dr.occa »

The idle mixture should be adjusted to factory and then the idle speed turned all the way out and then turned in until it just makes contact. Once it makes first contact then turn it in about 1 to 1.5 turns. It might even be 1.25 from first contact.

All vacuum lines and idle up vacuum solenoids, etc must be properly routed and with no leaks for the factory carb to work correctly and get a proper idle.

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Re: 4A-C help

Post by BlackStar »

I'll try to idle screw tomorrow, along wiht a tvsv that i icked up recently. my tvsv broke, and i tried to repair it. it could be what is causing the headaches.

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Re: 4A-C help

Post by dr.occa »

That TVSV is so ugly and a PITA. Also, try spraying the throttle plates with carb cleaner and open and close em a few times to work the built up turd out. Sometimes the throttle plates tend to stay open or shut due crud at their pivot points from over the years.

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Re: 4A-C help

Post by BlackStar »

I tested my repaired TVSV, it was completely non-functional. At any temperature it lets air go whichever way it pleases. The one i got at the junkyard actually worked(at low temps it doesn't let air go through L) I'll start the car up today and se how it goes, could very well be my problem.

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Re: 4A-C help

Post by dr.occa »

I'd like to hear if it fixed your problem.

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Re: 4A-C help

Post by BlackStar »

Actually did some work today. First i tried the car with the working TVSV, car still wet and high idled, and kept climbing. Shut off the car, backed off the idle screw, and it went even higher, now over 4000 rpms. backed off the idle screw, and the car wouldn't even start! pulled off the air filter, and sure enough, the carb was flooded.

Looks like I am going to learn how to rebuild a carb. I have two, so at least i can maybe do what i did with my engine, take them both apart and make 1 good one. My guess is that this carb runs way to rich.

pretty defeated now :(

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Re: 4A-C help

Post by dr.occa »

Sorry to hear the TVSV wasn't the culprit. Doesn't sound like a defeat but



A CHALLENGE!
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