Engine idle drops and dies after cold cranking?

Tiny
STEVE W.
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Only at idle, what does it do if you slightly increase the engine speed while setting? How about this test, Put it in drive and hold the brakes, now turn the blower to high, the headlights to high, wipers on. How does it act now? Trying to see if maybe it's electrical, did you do a fuel pressure test on it?
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Wednesday, March 25th, 2026 AT 4:50 PM
Tiny
ETERNALARIANNE
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I did an battery load test using a tester with everything cranked to MAX and the voltage was within spec and steady. I haven't checked the fuel pressure I have to see if my neighbor can find his gauges.
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Wednesday, March 25th, 2026 AT 4:53 PM
Tiny
ETERNALARIANNE
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Also, I've noticed a chattering sound when accelerating, could a valve adjustment fix all of these issues? It's been over 100K miles since it was done last time
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Thursday, March 26th, 2026 AT 12:01 PM
Tiny
STEVE W.
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It wouldn't hurt if it's been that long, however they normally wear and gain clearance and clatter. You said it ran better for a while but now acts up, did you disconnect the battery when you did the other work? I'm wondering if maybe there is a different issue. If you did, unhook it again, let it set a few minutes and reconnect and see if it still acts up? It might still be fuel related but on the other end, the idle is controlled by the throttle body and there is a relearn procedure that it follows and then adjusts over time, however if the throttle body is dirty inside it can cause a low idle as the throttle doesn't compensate properly.
Take a look in the throttle body and see if it has any built up crud, soot. If it does clean it and see if it helps. Book says you need to pull the TB to clean it, but if you have access I generally don't, instead I use a dowel rod wrapped with a towel and spray that with cleaner and scrub out the bore.

https://www.2carpros.com/articles/throttle-actuator-service
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Friday, March 27th, 2026 AT 9:48 AM
Tiny
ETERNALARIANNE
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I actually tried to clean the throttle body when I changed the oil last, but couldn't get the air cleaner hose off due to some hard-line hoses connected to it that I couldnt get off. I guess I'll end up taking it all apart anyways to adjust the valves since it's clattering.
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Friday, March 27th, 2026 AT 10:34 AM
Tiny
STEVE W.
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Sounds like a plan.
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Friday, March 27th, 2026 AT 11:19 AM
Tiny
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Ok after reading about how to do the valve adjustment, I ended up making an appointment at the Honda dealer to get it done.

Today I was sitting there idling in a parking lot and out of the blue the CEL came on (finally) but I didn't notice any shuddering or idle drop. Checked the codes and it was "system too lean" on bank 1 and 2. I forgot to mention when I tried to take the air cleaner hose off to clean the throttle body, the hose had a few splits in it, so I guess it's sucking too much air? I got a new hose I'm going to take with me and let the dealer put it on when they adjust the valves and clean the throttle body, hopefully that fixes the issue.
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Saturday, April 4th, 2026 AT 5:49 AM
Tiny
STEVE W.
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Yep, split hoses can do that as they will cause it to run lean and may cause the other issue you have as well. At idle is when the engine creates the highest vacuum and cracked hoses would cause it to act like it has low fuel pressure and run out of gas. Might want to stick the new hose on and see how it acts. May also want to get a can of carb cleaner and spray some around the other hoses. See if any others are pulling in air. Then if it runs good with no issues you can save some money, unless they are not charging you a ton for the valves.
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Saturday, April 4th, 2026 AT 4:18 PM
Tiny
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Ok valve adjustment, throttle body clean, and new intake hose all done today. Here's hoping that fixes everything!
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Friday, April 10th, 2026 AT 4:15 PM
Tiny
KEN L
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Please let us know, STEVE W. Is one of our best!
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Sunday, April 12th, 2026 AT 8:05 AM

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