Help identifying a part

[AMC Diplomat]

I'll admit I have no idea what the hell the two black little cylinders circled in yellow are called. Obviously not my engine bay because it is way too clean. What are these things called?

 

[Duke5A]

They're vacuum solenoids for the catalyst system. If you convert to s standard electronic ignition they can be removed with tons of other junk.

 

[AMC Diplomat]

Thanks. One is ticking loudly and it's super annoying.

 

[Duke5A]

That's a vacuum leak and will cause the motor to idle high. Probably a cracked hose or the solenoid body is cracked. Needs to be fixed, or removed with an ignition swap.

 

[AMC Diplomat]

Well that explains the strange idle. Sometimes it's a little high but not terrible, sometimes it's wtf shut it off its way too high. This car is just one in the fleet though. Definitely not my go to car for everyday A to B. If I get into putting an ignition into it, then I might as well buy a 360 or even a lower mile 318 from a junkyard and make it nice.

 

[AMC Diplomat]

I have a follow up question. I started following the vacuum lines and I found this one plugged. I have no idea where this is supposed to go. Does anybody have any ideas?

 

[GregG48213]

any ideas?

From where it's located, I would guess that it goes to the air pump. There should be a sticker under the hood with a diagram for the vacuum lines. These are also found in the factory service manual.

 

[AMC Diplomat]

The un-goobering continues

 

[SonOfaTomP]

Thanks. One is ticking loudly and it's super annoying.

is your "ticking" similar to this?

 

[SonOfaTomP]

I have a follow up question. I started following the vacuum lines and I found this one plugged. I have no idea where this is supposed to go. Does anybody have any ideas?

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i believe that goes to the bottom of the air cleaner

 

[LSM360]

i believe that goes to the bottom of the air cleaner

I think so too and I don't think there's a vacuum line like that to air pump and that idling video definitely sounds like car has a serious vacuum leak or faulty lean burn computer. Some of that ticking sounded like fan, clutch or pulley.

 

[Mikes5thAve]

Check the vacuum sticker on the hood like Greg said, that'll tell you what's not hooked up properly.
I looked at the manual and there is a vacuum connection to the air pump that ties in near those relays.

 

[AMC Diplomat]

Vacuum diagram under the hood? lol that's gone
Air pump? Well someone deleted on that too

It looks like someone looped the vacuum lines on the solenoids from the bottom of one to the top of the other? This just doesn't look right but I could be wrong

The lack of an air pump explains a lot

 

[Mikes5thAve]

The top of at least one of the solenoids should be open.
No air pump confirms where that line went then.
It's rare for the label to be missing it should have been in the cut out near the front of the hood. But here's from the 87 manual

 

[AMC Diplomat]

The top of at least one of the solenoids should be open.
No air pump confirms where that line went then.
It's rare for the label to be missing it should have been in the cut out near the front of the hood. But here's from the 87 manual

Thanks I appreciate it. One of the previous owners was just was a complete idiot with this car. With how bad the paint is cooked off the hood I'm not surprised the sticker is gone.

Update: I undid that loop on the vacuum solenoids. Now it only ticks when I hit the gas when its in park and then stops. It was ticking all the time in park before. So I'd call that an improvement.

 

[Aspen500]

Originally there was proably a tiny foam filter on the solenoid vent port(s). They generally only last a couple years before the deteriorate and fall off.

 

[AMC Diplomat]

Originally there was proably a tiny foam filter on the solenoid vent port(s). They generally only last a couple years before the deteriorate and fall off.

I'm still confused as to why someone would loop one to the other. And deleting the smog pump... like did they think it would help on this crappy set up?

 

[Mikes5thAve]

Maybe someone thought something was missing and they were supposed to be looped?
People used to remove air pumps thinking it robbed power. If they did it was probably minor but they can also seize up if they sit for a long time so maybe that's what happened?

 

[AMC Diplomat]

Maybe someone thought something was missing and they were supposed to be looped?
People used to remove air pumps thinking it robbed power. If they did it was probably minor but they can also seize up if they sit for a long time so maybe that's what happened?

All it's really doing is sealing my driveway right below the tail pipe at cold start. Idk what fun stuff is in that cold start exhaust but man does it coat the asphalt really good

 

[Aspen500]

It's just soot combined with water vapor in the exhaust.

I always got a kick out of people taking the air pump belt off for "more power and better mpg". An air pump takes about 1/4 hp to turn. Kind of like blocking the egr valve because it robs power. At anything over about 75% throttle opening, it isn't open anyways.