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- #121
fresh desmog, no start. DIAG (1 Viewer)
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- #122
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- #123
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- #124
Okay.
Part one: first start of the day. Here's a video. in the end of the video I back the idle screw Out fully and there's no change in idle. Still high at 1000. IDLE SCREW DOES NOTHING.
Part two: turned off and let it sit for 10 minutes, then start it again. Rough idle or won't idle until I raise the IDLE SCREW Again... it works again. But after a little
I can pull the IDLE SCREW back out fully and it will still be high. So the IDLE SCREW works 50% of the time.
^ after this video I was able to adjust the carb and get vacuum Stable at 20. idle will still be high. * But I know that if I drive it, turn it off and let it sit it for a bit, that it will run rough again when I start and will have to adjust the carb every time I start the car.
Part one: first start of the day. Here's a video. in the end of the video I back the idle screw Out fully and there's no change in idle. Still high at 1000. IDLE SCREW DOES NOTHING.
Part two: turned off and let it sit for 10 minutes, then start it again. Rough idle or won't idle until I raise the IDLE SCREW Again... it works again. But after a little
I can pull the IDLE SCREW back out fully and it will still be high. So the IDLE SCREW works 50% of the time.
^ after this video I was able to adjust the carb and get vacuum Stable at 20. idle will still be high. * But I know that if I drive it, turn it off and let it sit it for a bit, that it will run rough again when I start and will have to adjust the carb every time I start the car.
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NeverGiveUpYota
Dare me.
Every time? Yea that's odd. Busy w/ my kid and making breakfast but hopefully the others will chime in their wisdom.
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Pop the throttle linkage off the carb throttle arm and verify the pedal is not holding up the idle speed.
If high idle problem persists, then remove carb and see if throttles are both fully closed with idle speed screw backed out.
If high idle problem persists, then remove carb and see if throttles are both fully closed with idle speed screw backed out.
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Visual aids.
Bottom of carb, primary throttle.
Part throttle, idle transition slot & ported vacuum orifices visible.
Primary throttle, closed to typical idle setting, idle transfer slot is only slightly visible.
Idle speed screw backed off so primary throttle is completely closed, reducing idle speed to zero.
HTH.
Bottom of carb, primary throttle.
Part throttle, idle transition slot & ported vacuum orifices visible.
Primary throttle, closed to typical idle setting, idle transfer slot is only slightly visible.
Idle speed screw backed off so primary throttle is completely closed, reducing idle speed to zero.
HTH.
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- #128
Ok, so I just disconnected the Throttle linkage and there is no change In idle. Idle screw is still doing nothing even tho it appears healthy. idles at 950 and vacuum is at 19-20.
( I can raise idle, but not lower ) On the first cold start of the day it will bounce from 650-750 for half a minute before stablazing at 950. (Not using choke, one pump of gas)
Is that a forsure diagnoses or is there ANYTHING else that could be causing this before taking off the carb.
1) is there anyway to try and push The plate into a fully closed position using the linkage outside.
2) And if I take the carb off and verify that it is slightly open, what do I do to close it.
( I can raise idle, but not lower ) On the first cold start of the day it will bounce from 650-750 for half a minute before stablazing at 950. (Not using choke, one pump of gas)
Is that a forsure diagnoses or is there ANYTHING else that could be causing this before taking off the carb.
1) is there anyway to try and push The plate into a fully closed position using the linkage outside.
2) And if I take the carb off and verify that it is slightly open, what do I do to close it.
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NeverGiveUpYota
Dare me.
I can't remember if this is your DD? I have my carb off now and the pixs that Jim added made me put mine in the sun and really examine the linkages and the butterfly flappers on the bottom and how they react to what. I took a bunch of pics but I won't add them here. I probably wouldn't make anything more clear for you but just to say if it's not your DD, it's not hard to pull it. Holding the carb and really watching how movements act on it is pretty interesting. I did note that one of the screws is different than the other three (on those butterflies) and one of my linkage plate arms whatever it's called appears bent in a way it should not be. I'll add pixs to my thread.
I'm sorry I'm not any real help. Only commiserating over the frustrations I know well too.
I'm sorry I'm not any real help. Only commiserating over the frustrations I know well too.
CuCruiser
SILVER Star
Not to bust your chops but Jim is the man and if he says so, I would do what he says.
Taking the carb off is a 10 minute affair.
Once you have the carb in your hand and can play with the linkages and see how they act on the valves you might have your answers.
Taking the carb off is a 10 minute affair.
Once you have the carb in your hand and can play with the linkages and see how they act on the valves you might have your answers.
Did you check the PCV valve? (didn't read back in all the posts)
At idle there shouldn't be any air flowing through the carb base pipe that leads to the VCV. That pipe entrance into the carb base (& VCV) are only there to vent the charcoal canister when the throttle is pushed down a bit. Is it plumbed up correctly?
Remove that hose going to the carb base pipe & plug that pipe. That will at least rule out a malfunctioning EVAP VCV.
An intermittent vacuum leak could simply be a sticking PCV valve.
At idle there shouldn't be any air flowing through the carb base pipe that leads to the VCV. That pipe entrance into the carb base (& VCV) are only there to vent the charcoal canister when the throttle is pushed down a bit. Is it plumbed up correctly?
Remove that hose going to the carb base pipe & plug that pipe. That will at least rule out a malfunctioning EVAP VCV.
An intermittent vacuum leak could simply be a sticking PCV valve.
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- #132
No, It's my only car but I work 3 blocks from home.
This is a game changer. I haven't touched the charcoal canister at all. The pipe off the carb insultator has a constant strong vacuum.
This is a game changer. I haven't touched the charcoal canister at all. The pipe off the carb insultator has a constant strong vacuum.
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A small clarification on that, the port/tube coming out of the spacer (part of insulator plate)under the carb that the VCV hooks to will have vacuum at idle as it is below the carb, it should show the same vacuum readings as the 3 prong fuel filter. The vacuum port on the VCV is tied into the other side of the carb by the valve cover via the BVSV. That is the side that the vacuum varies on with throttle position.
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NeverGiveUpYota
Dare me.
Correction. The pipe from the black carb insulator goes to the VCV (I had mine capped). The one sorta below and to the right facing side and points extreme to extreme right goes to the PCV. This is the pipe that I said above was totally clogged on mine when I pulled that whole section off the side of the intake manifold.
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gregnash
Anal Retentive Analyst
Based on your second video I am thinking a leaky valve or possibly spark plug gap issue?
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- #136
i don't think so, @gregnash because it only acts like that when the car is turned back on after being off for a little. That was the purpose of the video is that 5 minutes before it was running very smoothly. I replaced the VCV with a spare, and adjusted air fuel and i believe that issue may be resolved, or atleast it has in the driveway. vacuum is more stable and slightly higher. I just detailed the thing so i don't want to drive in chicago dirt rain
The Canister purge system works as follows: The port on the VCV circled in green is the vacuum coming from the other side of the carb through the BVSV, there shouldn't be any significant vacuum on this line at idle as the throttle plate is closed and the 'ported vacuum orifice' as in Jim's pic isn't pulling vacuum. As the throttle plate opens, vacuum is applied here to open the VCV ports so the canister line 'connects' to the line going to the insulator plate port (red arrow). If the motor is not warmed up, the BVSV does not allow the vacuum to pass (that's the whole purpose of the BVSV), it allows the vacuum to pass once the temperature is reached. The port marked with a red arrow, will have vacuum at idle and will behave with the same characteristics as the gauge you have running in the cab. It is below the carb so that is the reason for this. So, as you open the throttle, the vacuum is applied to the VCV and air will be allowed to flow into the port below the carb as marked with the white line/arrow. When you use a mighty vac to check the VCV, the port (S) circled in green should hold vacuum.
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- Thread starter
- #138
Thanks!
I think it's all hooked up correctly, I was referring to carb insulator pointed in red. I replaced the vcv with another one and I now can maintain the same driveability to and from places... before vacuum would drop and idle was rough at first
Im debating removing the carb and checking beneath right now but I'm kinda lazy
I think it's all hooked up correctly, I was referring to carb insulator pointed in red. I replaced the vcv with another one and I now can maintain the same driveability to and from places... before vacuum would drop and idle was rough at first
Im debating removing the carb and checking beneath right now but I'm kinda lazy
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- Thread starter
- #139
I read a thread where this happened to customer of marks and said it could of been an error during rebuild? Or did I somehow fxxx up. I'm pretty confused and regretting staying with an Aisin. I've treated the carb like a baby since recieving it.
Jim, how do I lower idle. The car runs amazing, starts with zero hesitation, vacuum strong at 20. It's perfect aside from this.
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- #140
