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76 Z starts but will not idle.


280Vette

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You might try raising the idle speed to keep it running, while you do more diagnostic work. The rusty screw next to the thing that had the wrong hose on it (Post #5) is the idle adjustment. Turn it out to let more air in and the idle speed will increase. Might be enough to let it idle. Then you can use the old trick of spraying carburetor cleaner (carbs!, yay) around the various spots where there could be a vacuum leak. Injector seals to the manifold, intake manifold/head interface, PCV hose, EGR fittings, etc. If idle speed changes while you spray the outside, that means there's a leak. Keep fixing them and things will get better.

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Sounds like vacuum issues to me too. Of course when you did the headers, you had to at least unbolt (maybe not remove) the intake manifold. Did you re-gasket both? These engines are notorious for their rusty studs and leaks around the #6 and (to a lesser extent) #1 intake runners. In fact on my engine, my #6 exhaust was blowing right into the #6 intake -- sort of an enhanced local EGR thing going on. ;)

I'm guessing all your vacuum lines are a lot more raggedy than you think. It's a cheap and easy project to replace the whole, sorry mess with new lines. Go buy a bunch of hoses/tubing at your local auto parts store, and go to it! Follow the diagrams in the factory service manual (far, far, far better than Hayes or Chilton's), which you can download for free here:

XenonS30

You might also replace that cracked intake boot, which will cause you to run leaner if/when it leaks. I don't know how you fixed it, but I would think a durable fix would be unlikely. That part is still available, as far as I'm aware. Courtesy Nissan might have it. Also check ebay (caution if dealing with reddit -- more expensive, with steep shipping).

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MSA also has that intake boot. I would be curious to see if it will idle if you do what ZedHead recommended. There's a few other things you can do while its running but you already have a lot of things thrown at you. No need to get more confused right now. See if you can get it idling and lets go from there. And then maybe post a video of it.

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post-29967-14150830303867_thumb.jpg

Im having a similar problem. My car has a Far 311 Race Cam which is dropping from 1,100 to 500 RPM whenever i get stuck on heavy traffic, stalls and then dies. I did indeed remove the EGR system as the Servo Diaphgram was damaged.

According to one of the members this is what i really have in my car:

"a L26 crank makes my motor 79 mm stroke instead of the stock 73.7 mm

stock bore is 83 mm for the L24 and the L26 motors

my block has been bored out 1 mm to compensate for wear

that makes my motor a 2.627 liter motor

your E88 head from 1972 will give you about 8.7 to 1 compression

FAR performance went out of business in 2002 so I have no cam specs

311 could be their advertised cam duration

if it is the same as BRE 311-------

BRE 240Z 311/C-1 cam: At 0.001" lift: In open 33 deg Bef TDC In close 66 deg Aft BDC Ex open 66 deg Bef BDC Ex close 33 deg Aft TDC IN Lift at TDC 0.108" Total Lift 0.463"

At 0.050" lift: In open 14 deg Bef TDC In close 45 deg Aft BDC Ex open 45 deg Bef BDC Ex close 12 deg Aft TDC

IN Lift at TDC 0.108" IN Lift Total 0.463"

EX Lift at TDC 0.097" EX Lift Total 0.469"

HOW DO I SOLVE THIS IDLE PROBLEM? ANYONE?

post-29967-14150830303231_thumb.jpg

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I did change the idle screw and now it'll run for about 30 seconds, and a lot healthier, so it is getting better. I can hear what sounds like a vacuum hiss when the engine is running so now I guess I just need to track the hiss down. Sounds like it's coming somewhere over the #1 and #2 injectors

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It does idle now for the most part. Still sounds rough and stumbles and stutters and dies sometimes when I give it gas. I used a new intake/exhaust manifold gasket for the install. I also just noticed I do not have any clutch pressure. I don't know if it's related but the clutch was working fine before this all happened.

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. I can hear what sounds like a vacuum hiss when the engine is running so now I guess I just need to track the hiss down. Sounds like it's coming somewhere over the #1 and #2 injectors

Carb cleaner does work if there's a leak. Idle speed will change when you spray it on the leak.

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The spraying of the carb cleaner is most effective on EFI systems. With carbs, you would spray at any connection points between the carbs and the head. The gasket surfaces and any vacuum hoses, like the big one for the brake booster.

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Seems like the #1 and #2 manifold bolt wasn't tightened down enough. Tightened it up even more, played with the idle screw and timing a bit and now it runs. Ran for 10 minutes straight with no issues. I have some fine tuning to do, but for now I'm just glad it runs. Now I think I have to replace the clutch slave and lines, I think they deteriorated from not being used, but that should be pretty quick and easy.

Thank you guys so much for the help

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