60 won't idle until warm (1 Viewer)

[Skeet]

The hesitation under load was solved by a Mark Algazy rebuilt carb. I chased the intermittent no-idle issue through the vacuum system numerous times until I wiggled the connection at the Emmission Control Module and it idled smoothly. Just resoldered the joints around the connector and will hopefully be good to go.

 

[g-man]

Do you mean the fuel cut solenoid wiring connection? Glad you got it resolved.

 

[NeverGiveUpYota]

Would seem since he posted a shot of the emissions board, he meant that and not the solenoid. That and the mention of reflowing the connections....
so it’s totally resolved @Skeet? Let us know if that was it. Did you pull the manifolds too?

 

[Skeet]

Resoldered EMC is in. Idled normally. Allowed me to tune the carb. Running really well. I’m optimistic.

 

[Skeet]

Never mind. Cranked it to ride down the road. Back to running way too rich, back firing on deceleration and won’t idle. I have known good ECM coming so I’ll give it a try.

 

[micruz60]

Friggin' idle issues.
Just to clarify, this is the ecm at the driver side footwell kick panel? And the connector was wiggled to help pinpoint the issue? I'm looking to do some preventative maintenance/inspecting on mine.
Did you also do the fuel cut solenoid mod as mentioned by g-man, or was that already on-board the Mark A rebuilt carb?
Thanks.

 

[Skeet]

Yes, the ECM in the driver's kick panel. Movement of the connector made it idle and led me to think its the problem with my deceleration fuel cut system. I haven't grounded the ICS to the carb body. I think that is a way to bypass the ECM if it's not functioning.

 

[morganism]

Do the EGR checks next. They cause really annoying issues if the rocks get sucked up into the valve from the cooler. You can do a simple check, once warmed up, put a longer length of vac hose on the tophat, use your mouth to put vac on the valve while tapping it with a screwdriver or wrench. If you here rocks rattle down into the oil pan, you know where the prob is.

If EGR working ok, it will attempt to stall on vac.

 

[Skeet]

EGR valve appears to be functioning

 

[morganism]

Does it try to stall on vac ?

Does the vac line off the top of the distributor cap shock you when you touch it while grounded? Cap could be carbonized on inside, and is sucking all the juice from the coil.

 

[mwebfj60]

Yes, the ECM in the driver's kick panel. Movement of the connector made it idle and led me to think its the problem with my deceleration fuel cut system. I haven't grounded the ICS to the carb body. I think that is a way to bypass the ECM if it's not functioning.

Before cutting up the ICS and grounding it out, there are a few checks you can do. The symptoms seem like this is a good place to look. When RPMs are above 1800 and vacuum at the decel diaghragm is high (throttle plate closed/ idle position) the ECM disrupts the ground that goes to the ICS. That’s why the ground mod normally works. You still have to have 12V on the yellow wire though. Good place to start would be checking there. Good luck.

Another thought would be to double check the choke operation. If you’re still in a stock configuration, when the BVSV heats and opens, it pulls the choke opener, forcing the choke plate open. Also the HAI diaghragm and HIC valve. That could cause a huge cold vacuum leak that seals at temp as the HIC closes.
I might have had this backwards in my head this whole time...have the FSM out for a resmog and looked at the HAI system just now.

Might help

Aisan Decel Fuel Cut Circuit

 

[morganism]

BVSV sounds right.

Double check the vac lines to the distributor, if wrong one off carb circuit, could be pushing advance around. You could also try the hose hack, of putting the hose closest to the body, to the one on the outside. plug the original outside vac line w golf tee.

HAC might be hosed wrong also, that circuit can bleed air in, but isn't supposed to at rest. Don't worry about the open hose at bottom, it is supposed to be open. There is a filter under the bottom cap tho...

Aisan HAC

 

[Skeet]

 

[Skeet]

Looks like a spliced wire coming out if the ICS bundle before it turns up to carb. Grounded to the manifold. Thoughts?

 

[micruz60]

Most likely that is the wire that goes to thermosensor that controls the carb cooling fan.

Edit: you could look underneath up to the manifold to verify this, I doubt it has any effect on idle. Certainly could be cleaned up with a heatshrink wrap or elect. tape?

 

[Skeet]

 

[Skeet]

Ah. That makes sense. Thanks!

 

[micruz60]

Looks sooty under the exhaust manifold, could be / probably a leak, causing the erratic idle and with the amount of rust on the j-pipe connection at the top-right of foto in post#36, I would recommend PB blastering (several times with pause of a day or so) that pair o' nuts and get the desmog kit with blockoff plate.

 

[g-man]

My guess bad vacuum connection or wiring connection. Check out your ignition system...plugs, wires, coil, ignitor, distributor. Make sure your vacuum lines are right and working. Best way to do this is pull each wire and plug one at a time and holding the plug close to ground metal with the plug wire still connected. Crank but don't fire the engine and check for spark. Spark should jump to ground if your within 1/8th to 1/16th of an inch. Do this with insulated pliers. Next check the EGR. Take a hammer to it and see if you can dislodge carbon build up inside while at high idle. Cut the engine off then pull the air cleaner top off and check the bottom of your air cleaner for chunks of carbon or powdered carbon coming from the EGR. Carbon build up can cause erratic idle and stalls at idle.

 

[NeverGiveUpYota]

What I see in that photo is the funky yellow blob. I zoomed in but still can’t get a good look. Could that be a shoddy crack repair?