Engine idle not working

[Fordication]

Here is another video. I will post 3 of them.

 

[Fordication]

I have only glanced through all the pages. But here's a thought...the car was purchased in Wisconsin and driven to Texas over a two-day period without these issues. After arriving at its new home, the issues popped up. I suspect the long drive and the constant heat soaking of the engine bay during this trip may have compromised a vacuum line somewhere in the engine bay and the constant poking around with fuel and ignition work may have made it worse. There are several vacuum lines that could cause an idle issue, all are easy to make contact with when working on the engine.

Let's not forget that the power brake booster could also be a contributor and could cause the largest possible vacuum leak of all. Sustained heat over a couple of days combined with the constant use could have cracked the diaphragm in the booster. In the process of checking ignition and fuel, I would have recommended you also perform a methodical vacuum line removal and isolation to verify there are no issues with any of these lines.

If it's in the shop, let's see what they come back with.

I wondered about that. The only problem is that line that I was not sure about. It appeared to be plugged in but it was never touched before the problem began. I flushed the master cylinder 2 weeks ago and installed a new gasket on the lid. I bled all of the breaks then emptied the fluid again and put in all new brake fluid. Even after that the brakes sucked. Seemed like all of the pressure was leaking out somewhere. So you may be onto something with that. I just took it to the shop.

 

[Fordication]

Here is a video of the muffler noise. This thing is really stinky like bad exhaust smell. Makes the whole car shudder and my wife wants to make me take a shower.

 

[Fordication]

Here is something new. After I installed a new coil and Ignition Control Module the voltage gage bounces all over the place during high idle.

 

[Fordication]

Not that this is your problem. Yet, If there is low voltage from the system I will not run good, I'm putting it here so you have it. At the battery the voltage should read 12.3 -12.5 v give or take. When charging it should be 14 v. Depending on the load.



This is for stock Mopar charging system.

1:With the key in the off position should have on the alternator output battery voltage.

2:The field wires should both read zero we should have no voltage.

3: If there is voltage at the field wires with the key off, there is a wiring problem.

4: If no voltage at the alternator output stud with the key off then we likely have either a dead battery or we have a wiring problem or blown fusible link.

5: With the key in the on position. there will be voltage at the alternator output, it's going to be lower than what it was with the key off, because the entire vehicle is energized. The voltage drop is going to be more you can still see it go from
12 and a half down to 11.7. Still going to have near battery voltage.

6: What's important. With the key on. The field wires should have voltage. It won't be full battery voltage but it's has power coming to the alternator and it will be a lot less on one side and one side is high. That's the inlet so that's power going into the field winding.
The other one, the one that's low is the output from the field winding.
The output from the field winding is what goes back to the voltage regulator.
The voltage regulator on this is simply a switch ( Remember it needs a good ground to function.) all it's going to do is connect this field terminal here to ground and when it connects it to ground electricity then flows through the field winding energizing it and causing the alternator to charge.

7: Run test: This is for stock Mopar charging system.
Before doing the run test you're going to want to connect directly to the field output terminal on the alternator with some sort of a jumper wire. You can remove the existing field wire if it helps you to get to it. Use a jumper wire that comes back to the battery and it's not connected to anything right now. Have the voltage meter connected to the battery. Just checking battery voltage 12.3 volts there abouts. By touching the jumper wire to the negative terminal.
Just grounding it you can hear the engine load up because it's pulling a load and the voltage runs up to 14. That tells you that when the field in the alternator is energized it's charging. The alternator is good. Now you know that it's not an alternator problem at this point. If it's not charging you have a no charge scenario but this passes then you know it's the voltage regulator or some wire to it. It's most likely the voltage regulator and that's all it takes to diagnose the charging system on one of these
Here again If the any ground is bad or loose. it won't charge correctly or reliability. They become phantom grounds that just keep haunting you! That being the Voltage regulator ground, chassis ground, engine ground, Bolts, bolt holes, nuts and mounting brackets. 99% of the time there overlooked. The whole car is a ground.

Ok so I took the voltage at the battery. 12.2 Volts
Voltage at the positive side of the coil is 9.6 volts while running. 5.5 volts with key in on position but motor not running.
Voltage at resister on top is 14.2 volts on bottom 14.2 volts. Both, on the right side. Left side is 9.6 Volts
Voltage at back of Alternator and all wires are checked is 14.2 volts going out during running. On the terminal on top, I just checked for the heck of it and its 13.2 Volts.
Took the voltage regulator lead off and measured on the left side of the connector while running and it was 12.2 volts.

So I am not seeing anything electrical at all. This is either a vacuum leak I cannot find or distributor or related components failed or the timing change lost a tooth. I tried to check the timing again today but I could not see a mark. I think I need to clean the balancer with sanding block or steel wool. However, I did get it running long enough to take it to the local classic garage. I gave them a list of everything I did and hopefully they will figure it out. To be honest, someone brought up the brake vacuum line and the master cylinder, it might just be a vacuum leak there that's kicking my ass.

 

[Fordication]

Here is a video of the muffler noise. This thing is really stinky like bad exhaust smell. Makes the whole car shudder and my wife wants to make me take a shower.

If only this was a radical cam doing this.

 

[HPP]

I wondered about that. The only problem is that line that I was not sure about. It appeared to be plugged in but it was never touched before the problem began. I flushed the master cylinder 2 weeks ago and installed a new gasket on the lid. I bled all of the breaks then emptied the fluid again and put in all new brake fluid. Even after that the brakes sucked. Seemed like all of the pressure was leaking out somewhere. So you may be onto something with that. I just took it to the shop.

You wouldn't have to touch it for it to develop a booster leak. The vacuum diaphragm is inside the booster canister. You couldn't see it even if it had failed catastrophically. However, it's entirely possible it developed a small tear and started leaking engine vacuum, making it impossible to get a good idle quality out of the engine, but still allowing the power brakes to function reasonably well. None of this would have any impact on the master cylinder or brake fluid. And this tear could have happened after you got home and parked it overnight and it cooled off and shrunk, creating the tear.

Its a simple test to check it. Unplug that hose from the manifold/carb nipple, plug that nipple. If idle improves, reattach the hose to the nipple and unplug the hose at the booster. This will help you determine if you need a new a new hose or a new booster. If it doesn't change, you've eliminated two variables and can continue testing other items.

I had this exact problem in a '74 D200 I used to have. Drove me nuts for a few weeks as I was chasing down spark, fuel, and checking the manifold and carb for vacuum leaks. I wasn't even thinking of checking the booster but a slip while climbing into the engine bay led me to lean on the hose and it pulled off the back of the carb. When that happened, the idle barely changed. When that hose came unplugged, it should have fallen flat on its face because that nipple is huge. I stuck my finger over the nipple on the carb and the idle smoothed right out at 750 rpm like there was nothing wrong. Re-attached the hose and the stumble came back. So, I turned everything off, used my Miti mini pump to put a vacuum load on the booster and watched the gauge bleed off pressure fairly quickly. Located a rebuilt booster, swapped it out, problem gone.

Boosters rarely go bad and if they do, it usually takes a long, long time. Odds are yours is original. Combined that with heat and a two-day road trip where it was constantly under pressure and being pressed for braking, it could certainly be a leading contender as the failure point.

 

[HPP]

Here is something new. After I installed a new coil and Ignition Control Module the voltage gage bounces all over the place during high idle.

May be nit-piking, but it's actually an amp gauge and not a voltage gauge. Amp gauges perform differently. Volt gauges will hardly ever move as it simply measure battery voltage. Amp gauge is measure current flow through the whole system. You should have seen it leaning towards the Charge side while driving and towards the Discharge side while idling at stop lights. Range of movement will be greater when using additional electrical accessories like lights, wipers, or a/c. To really see it drop, turn everything on at idle and watch it fall. When I was using a vintage Mopar as a daily driver, night time driving in the rain was always a bit of a challenge.

Replacing the coil and module wouldn't directly cause this movement, but moving wires and disturbing connections can create issues in places you weren't working and where there were none previously that could result in seeing something like this. Especially since you have a factory a/c car. All the amperage of the system comes from the alternator, into the bulkhead connector on the firewall, and into this gauge on the dash before being distributed to everything else. Any connection anywhere in the system, to include the alternator itself, could cause a slight fluctuation like this.

You have plenty of other issues you are chasing down right now, so I wouldn't immediately worry about this, but keep this in mind: You may want to inspect the main firewall connector to make sure it is in good condition. I have seen numerous a/c equipped cars burn up wires at this firewall junction. There was a factory service bulletin released back in the '70s that outlines how to fix this issue to avoid the overloading of these wires. Here is a good technical video about it. https://www.youtube.com/watch?v=5i-0GVm0Ax8 There are other suggestions out there that say bypassing the ammeter entirely is best. That also works, but I prefer to keep the wiring pretty close to factory to aid any future troubleshooting. Using a factory authorized fix for this is a good approach, IMO.

 

[Fordication]

You wouldn't have to touch it for it to develop a booster leak. The vacuum diaphragm is inside the booster canister. You couldn't see it even if it had failed catastrophically. However, it's entirely possible it developed a small tear and started leaking engine vacuum, making it impossible to get a good idle quality out of the engine, but still allowing the power brakes to function reasonably well. None of this would have any impact on the master cylinder or brake fluid. And this tear could have happened after you got home and parked it overnight and it cooled off and shrunk, creating the tear.

Its a simple test to check it. Unplug that hose from the manifold/carb nipple, plug that nipple. If idle improves, reattach the hose to the nipple and unplug the hose at the booster. This will help you determine if you need a new a new hose or a new booster. If it doesn't change, you've eliminated two variables and can continue testing other items.

I had this exact problem in a '74 D200 I used to have. Drove me nuts for a few weeks as I was chasing down spark, fuel, and checking the manifold and carb for vacuum leaks. I wasn't even thinking of checking the booster but a slip while climbing into the engine bay led me to lean on the hose and it pulled off the back of the carb. When that happened, the idle barely changed. When that hose came unplugged, it should have fallen flat on its face because that nipple is huge. I stuck my finger over the nipple on the carb and the idle smoothed right out at 750 rpm like there was nothing wrong. Re-attached the hose and the stumble came back. So, I turned everything off, used my Miti mini pump to put a vacuum load on the booster and watched the gauge bleed off pressure fairly quickly. Located a rebuilt booster, swapped it out, problem gone.

Boosters rarely go bad and if they do, it usually takes a long, long time. Odds are yours is original. Combined that with heat and a two-day road trip where it was constantly under pressure and being pressed for braking, it could certainly be a leading contender as the failure point.

You are going to make me run to the repair garage and try that, you know that right? Damn.

 

[HPP]

You could always try it and see! Tell them you had an epiphany and wanted to check it out before they start. If it works, then you've saving paying for hours worth troubleshooting. Since they aren't going after a specific repair, I bet they quoted a flat rate per hour for testing, whether they find it or not. I also notice another vacuum cannister on the passenger side of the engine. This could have a similar issue since it has a diaphragm within it as well.