This issue is nothing new, a couple months
Did anything unusual happen just before? You replaced or disconnected the battery? You tanked up at a station you normally don’t use? etc?
Not that i could tell you, this issue happened when my father would drive the vehicle and he doesn’t know anything either
Based on that, have you ever checked for a vacuum leak? Bad connections, old hoses, etc?
Sounds to me like some manner of vacuum leak is a possibility.
I bought a smoke tester off Amazon and hooked it onto the intake hose that goes down to the throttle body, didn’t see any leaks that way
Vacuum means it is sucking in not under pressure. You can try spraying water on the connections to see if anything changes but usually just an inspection is revealing.
The old studebaker hose came off entirely and ran terrible. That was 50 years ago though.
That won’t help much. First, the throttle body has the throttle plate in it so all you really did was test the intake snorkel. But even then maybe not as the smoke tester very likely produces no pressure, whereas a running engine does. It’s negative pressure (vacuum) on the order of something like 18-22 inches of mercury - figure in the neighborhood of a 10 psi equivalent.
Take a butane or propane torch, and stick a small length of hose on it. Idle the engine, turn on the torch gas - but DON’T LIGHT IT! - and feed some gas all around the intake manifold and any vacuum lines you can see. If it hits on a leak the engine will respond. Alternatively, vacuum leaks hiss - forget the torch, stick the piece of hose in your ear and use it like a stethoscope.
I have no idea whether you have a vacuum leak. But rough idle that smooths out by adding some throttle is one way they can present.
I’ve tried this with a can of carb clean and couldn’t find anything, is there any other hoses i could hook up the machine to look for any bad hoses?
Out on a limb here but not just hoses but things like the intake manifold and leaky gaskets.
Suggest to test the brake vacuum booster holds vacuum. I do that w/a hand-held vacuum pump gadget called “Mity Vac”.
Small vacuum leaks can cause the check engine light to illuminate, vacuum leaks cause the fuel trim values the become out of normal range.
Misfires cause PCM faults, failing ignition coils cause PCM faults.
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Was driving this night and realized at the red light while the engine is rough idling the headlights are flickering too very subtle but it’s flickering, does that point to anything?
Charging system, also check battery cable (terminal) ends for corrosion and make sure you can not move them at all, have to be tight, check for corrosion at the grounds…
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Got in the car just now and got a code, P0441 evap system incorrect purge . What can I do to fix this? And does it have any correlation with the idle?
The purge function is part the engine’s evap system. When you re-fill your gas tank the evap system directs the gasoline fumes that were in the gas tank into the evap canister. That canister has to be emptied of the gas fumes before the next re-fill. That’s what the purge function does. The car’s computer opens the purge valve during a driving condition when the extra gas sucked from the canister won’t affect the mixture too much. Freeway speed driving would be a good time for that. If the purge valve is open during idling, especially cold-engine idling, that could cause a poor idle.
As for fixing it, a mechanic would inspect the purge valve, usually a simple electric-actuator controlled valve. Sometimes there is something obvious, like a tube to or from the purge valve is split. Then they’d replace the tube, not the valve. If nothing obvious then they’d probably replace the purge valve on a flyer. The old one might be stuck or clogged.
Purge valve problem reports are pretty common here, you can see for yourself using the forum search feature, link upper right this page. Best of luck. Hopefully a faulty purge function is the problem for the rough idle, and the diagnostic system finally found it. Often this fault will show up in a fuel-trim test, but not always.
Have you ever done that yourself ? It is a waste of time . Too many threads get sidetracked , the person with the problem hardly ever returns with the results .
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So, you can plug the purge valve as a test and see if idle is better? To see if it is stuck open? Or have a cracked line?
Is it simple enough to do it at home? If a mechanic is necessary I can definitely take it to him no problem and also if it does fix it I’ll let everyone know with a reply in the forum