i have an 88 wrangler yj and it starts fine but idles very high at first. for the first 10 or 15 minutes it will idle at almost 3000 rpms when either in nuetral or when clutch is in. when i have the clutch in half way it will idle at half that. when i put it in gear it will take off as i gradually let off the clutch because the rpms are so high. when the clutch is completely off the rpms are fine. when i looked at the carburetor the choke was totaly open and there was a lot of gas squirting out for just idling. i closed the choke a little bit by hand and the rpms dropped but the gas was still coming out at the same rate, as soon as i would let go the choke would open back up and idle at 3000 again. i have the 4.2 liter straight 6. anyone with an idea is greatly appreciated.
It's your electric choke. I had the same thing happen. I un pluged it and un bolted it.Bouht a new one a year ago and still have not put it on. It is fine with out it.
If the choke is open and it's still idling that high, it sounds like the fast idle cam is stuck. Look over by the idle speed adjustment screws on the left side. I think you'll find the fast idle screw sitting on the top step of the fast idle cam.
The only thing I can think of that would be affected so much by just letting the clutch pedal out in neutral would be that the body has lost it's ground and is stealing one through the clutch pedal. I have seen that happen with the brake pedal and gas pedal and gear shift and radio and... anyway.
There should be a wire mesh strap that runs from the rear of the engine head to the firewall. This does go bad.
It doesn't sound like the choke is working proper either, but that would have no bearing on the position of the clutch pedal...
A carb kit is only about $20.00 or so and is easy to put in them.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N> i have an 88 wrangler yj and it starts fine but idles very high at
OK, is this a new thing? Anything else happen or get changed?
It idles proper at 650-700 when warmed up?
A blown canister can cause a high idle, but that normally stays high.
Some had this vacuum solenoid valve behind the carb that can blow an open into the PCV system if it isn't working right or is stuck. It should be affected by the engine warming up too.
Has anyone been messing around with the vacuum line plumbing or working near any?
I would first verify what bllsht pointed at, the fast idle cam being stuck as that is very common. The fix is a clean with carb cleaner spray.
Next I would have the engine off and cold and give it two shots on the throttle like you should for a normal start, then open the air filter without starting it to verify the choke is closed.
I was thinking electrical due to me misreading your clutch settings and agree the basics should be looked at before messing around.
i checked the cam but it is moving fine. when i hit the throttle the cam moves as the screw lets it and the choke closed. when i started the car the choke opened a little bit but still idled at 2000 and spit gas out very fast.
i checked the cam but it seems to be moving fine. when i hit the throttle the choke did close all the way. when i started it the choke opened a little bit and still idled at 2000 rpms.
That sounds almost correct. It just sounds like a slight tune up adjustment is needed.
It 'should' only idle at 1750 when first started.
The choke linkage should have the fast idle cam sitting on the screw at the second from the end step when the engine is cold and off after punching the gas to close it. You then turn this screw to get it to come down to 1750 rpm once it starts.
The next step should be around 1400 rpm and the first step should be around 1100 to 1200 rpm.
I have mine so the first step is a 1200 rpm fast idle 'when warmed up' for my hand throttle and winch use which gives me the correct 'factory' setting of 1750 rpm at full choke when cold.
If you don't have the factory book for your Jeep, the Haynes CJ manual is the best one for your engine and it's basic controls as well as the engine bay wiring harness which matches the 86 CJ7's 258.
Oh, if you unplug the choke it just closes and the engine will not run for more than a couple minutes.
You 'can' easily put a manual choke cable on it like I did, but yours sounds like it is almost working perfectly.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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im actually starting to think that the cam was stuck somehow because when i moved it manualy the rpms dropped. thanks for the help with that. also, is there a way to adjust the air/fuel mixture without a gauge, i have a feeling its not set right due to the fact that i just got 28 miles from almost half a tank. i believe i know where the screws are to adjust it. theres two on the side closest to the front of the car towards the bottom of the carburetor, they also look like they are intentionly countersunk to prevent unwated movement. Im 90% sure its not the original carburetor so i doubt youll be able to tell me exactly where they are. but if there is a way cheaper than buying a gauge i would love to hear it
this is the second time im writing this, i dont know why its not showing up but anyways...i think the cam was stuck, i moved it by hand when the car was on and the rpms dropped. ive been runnin the engine and the choke seems to be working fine. also, is there a way to adjust the air-rule mixture without a gauge.
There is a computer adjusting the mixture via the O2 sensor and a POS Ford emissions computer.
The mix screws down front are only for the idle and the base setup for the carb. They are 'supposed' to be blocked off with a plug. They will not affect gas mileage a lot.
You 'can' mess with the idle mix screws, but as soon as you get them out of adjustment, the computer will kick in and adjust it back to where the O2 sensor says it should be, Basically you can carefully look down the carb and watch the pin at the center back of the carb move as you mess with the idle mix screws. It should hover around half way out when the mix is right.
You should also be able to see this pin move when you choke it a bit or give it a bit of throttle. It moves in steps.
You 'really' don't want to start messing with the high speed mix inside the carb.....
Has it ever passed emissions? Is all the emissions junk still on there? Is it required where you live?
'I' can remove the emissions computer and still get all of them I have done this to to pass emissions here in Canada easily, but I am really good with carbs it would seem. Well, lots that call themselves 'mechanics' just plain don't believe no matter how may sets of pass papers we show them but hey...
They just can't figure how a carb and engine can be tuned without a computer running things, they don't know we used to do it all the time in the analog days....
It is called the 'Nutter' bypass and is supposed to be for off road only but with a few tricks it is fine for on road. It gives a sweet 25% seat of the pants power boost with a red line of 4400 instead of 3500 and at least an extra 10 mph per gear. We also all get over 20 mpg with them highway. Mine gets 11L/100km or about 23 mpg but it is light.
Now attach the disconnected vacuum line from the distributor to a tee that you will have to install in the the ported vacuum line. The ported vacuum line is attached to a fitting on the BBD carburetor located on the side towards the valve cover, about 1/2 way up the carb......could you explain this to me in an easier way
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