84-85 Trucks & 4Runners 2nd gen pickups and 1st gen 4Runners with solid front axles

misfire all of a sudden?

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Old Jan 10, 2015 | 10:02 AM
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misfire all of a sudden?

Got new windshield and muffler welded on the other day. About a 50 mile trip, parked it, and this morning it barley ran. I did noticed one of the welds between the cat and the muffler didn't hold. I find it hard to believe that would cause it to barley run. What happened? Coil maybe?
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Old Jan 10, 2015 | 05:05 PM
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Got gas coming out of tail pipe also....new wires cap rotor and plugs...
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Old Jan 11, 2015 | 10:44 AM
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Ok...50 degrees today and truck cranks fine....been about 15 degrees on days it was misfiring and spitting gas. Coil worse on cold days?
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Old Jan 11, 2015 | 06:57 PM
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Uhhh....help
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Old Jan 11, 2015 | 07:35 PM
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Spark plug wires connected correctly? Check engine light on?
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Old Jan 11, 2015 | 07:43 PM
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Originally Posted by rworegon
Spark plug wires connected correctly? Check engine light on?
Yep wires and plug are good. No check engine light.
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Old Jan 12, 2015 | 04:38 AM
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What engine?
All the vacuum hoses good and in place?
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Old Jan 12, 2015 | 04:53 AM
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Originally Posted by rworegon
What engine?
All the vacuum hoses good and in place?
Yep...all good...sprayed for leaks...none
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Old Jan 12, 2015 | 06:19 AM
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You have fuel coming out of the tailpipe? You sure it isn't water?


If your truck is carbureted your carb is dumping too much fuel in, if it's injected one of your injectors is installed wrong or is stuck open allowing fuel to pour in. If you are really getting raw fuel out of your tailpipe DO NOT crank your truck without removing all spark plugs as you may have a hydro-lock condition.


Confirm fuel is coming from your tailpipe.
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Old Jan 12, 2015 | 06:35 AM
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Originally Posted by jimbyjimb
You have fuel coming out of the tailpipe? You sure it isn't water?

If your truck is carbureted your carb is dumping too much fuel in, if it's injected one of your injectors is installed wrong or is stuck open allowing fuel to pour in. If you are really getting raw fuel out of your tailpipe DO NOT crank your truck without removing all spark plugs as you may have a hydro-lock condition.

Confirm fuel is coming from your tailpipe.
Now I'm second guessing the gas from exhuast. Could have been condensation mixed with fumes. It is carbed. My electric choke hasn't turned on since it happened. Possible choke malfunctioned? Allowing gas to pour in the carb?
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Old Jan 13, 2015 | 03:44 PM
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Originally Posted by mikeyd6789
Now I'm second guessing the gas from exhuast. Could have been condensation mixed with fumes. It is carbed. My electric choke hasn't turned on since it happened. Possible choke malfunctioned? Allowing gas to pour in the carb?
Yes, it is unlikely it was fuel.

You get the priviledge of going down the list: spark, fuel supply, compression, etc...
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Old Jan 14, 2015 | 04:56 AM
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Another sub freezing day. Ran good and smooth for a about 30 seconds. Then crazy misfiring again.
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Old Jan 14, 2015 | 06:19 AM
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Sounds like a fuel system problem. Restriction, pump pressure or volume. Most likely it's a carb tuning issue. Could be an ignition issue but usually this kind of problem lies in the fuel system.

Check spark and ignition timing. If your timing isn't jumping around (loose rotor) and you have spark it's time to look at the fuel filter, pump pressure and flow and retune the carb according to manufacturer specs.
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Old Jan 14, 2015 | 06:24 AM
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Also, electric chokes do not turn 'on' the choke, 12v heats up a spring and pulls the choke open. If your choke butterfly is closed it will make your engine run rich. Manually set your choke full open if it is not hooked up to constant 12v.

Is this a Weber or factory carb?

Last edited by jimbyjimb; Jan 14, 2015 at 06:25 AM.
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Old Jan 14, 2015 | 06:35 AM
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Originally Posted by jimbyjimb
Also, electric chokes do not turn 'on' the choke, 12v heats up a spring and pulls the choke open. If your choke butterfly is closed it will make your engine run rich. Manually set your choke full open if it is not hooked up to constant 12v.

Is this a Weber or factory carb?
Weber
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Old Jan 14, 2015 | 08:20 AM
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You can adjust your choke full open by loosening the three small screws on the pass side of the carb and rotating the plastic housing fully to the right. Leave your choke open until you wire it to 12V keyed.
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Old Jan 14, 2015 | 08:22 AM
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I actually have it wired to the factory wiring harness. Red wire.
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Old Jan 14, 2015 | 08:34 AM
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When engines are cold they require less air and more fuel. A choke provides this service by restricting airflow into the venturi. If your choke is too far closed at idle the truck will run rough. With an electric choke, the choke will not open until the spring inside the choke housing is heated sufficiently by the 12v source to open it. While there could be many things causing this problem, a simple choke adjustment is a likely culprit for this exact issue.
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Old Jan 14, 2015 | 08:38 AM
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I'm going to definitely check that this evening when I get home. When it does crank like it's suppose to the choke is not engaged. When it is, you know it with the weber. Rpms go way up.
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Old Jan 14, 2015 | 08:56 AM
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Fast idle and choke butterfly adjustments are independent on the Weber. One means nothing to the other. You can have a perfect fast idle and your butterfly can still be off.
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