Weird idle issues

Jpocolypse

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I recently bought a new (to me) 6GA it's a 2002 coupe with a M/T. It seems to run fine except when idling once its warmed up. RPMs are around 750 which seems normal but it has a bit of an irregular shake to it and if you listen to the exhaust it sounds like it has a misfire but it doesn't have any sort of pattern to it. It's just random. I have already swapped spark plug wires and distributors with known good ones and the dealership i bought it from said they replaced the spark plugs. Also the long term fuel trim is around -5.5 and the short term fuel trim is anywhere from -18 to -28 at idle but is usually around 0 when driving.

Other info:
has 133,000 miles on it
needs to have the timing belt replaced because I don't think its been done
ABS and SRS lights are on
I just changed the oil and filter
Have not tried cleaning the throttle body yet
I have another 6GA with the same motor so I can try swapping just about any part
Sometimes you have to crank it for a while before it starts, but it always does start
There are no codes stored in the computer
when its in neutral and you give it a little bit of gas then go back to idle the RPMs bob around a bit before stabilizing
if I pull the clock backup fuse or disconnect the battery the car will just barely run until it adjusts the fuel trims back to where they were
I have a compression tester but haven't tested it yet but it doesn't sound like it has a weak cylinder when cranking

I tried to give you as much info as possible but if you need more just let me know
 

Jpocolypse

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Not yet I still need to figure out how to do that and as of tonight I have bigger clutch related issues which I posted about in the urgent section.
 

Jpocolypse

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I cleaned the throttle body and replaced the gasket. I also replaced all the spark plugs and tested the compression while I was at it. It still idles rough and according the the plugs and my scanner the engine is running very rich
(LTFT -3, STFT -24 (at idle and warm), Spark plugs: very black) . I ordered a new map sensor at the dealership (they actually price matched Majestic Honda ). In the morning I'm gonna go back and pick it up then install it. Hopefully that fixes it. Also I checked the TPS with my scanner and it seemed to go up nice and linearly as i pushed the gas pedal. On a positive note the compression was between 197 and 202 psi on every cylinder.
 

Jpocolypse

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A little bit but it actually runs better if I create a small vacuum leak. The engine is running rich for some reason
 

james'99

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Could be a bad A/F sensor but I would run a half can of seafoam through the gas tank and maybe seafoam the engine through a vacuum line
 

Jpocolypse

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I already ran an entire can through the gas tank and half in the oil then switched over to full synthetic about 100 miles after putting it in the oil. The first thing I want to try is swapping IACVs between my 2 accords and see if that solves the issue.

Update:
Just went through an entire can of carb cleaner trying to clean the IACV and when I put it back together and tried to start it it wouldn't unless I gave it gas then it would die as soon as I let off. Time to go back and check everything

update update:
Some how it got clogged, but I managed to unclog it. Now it does have a vacuum leak because I had to reuse the old one. (the new one will be here tomorrow morning) Hopefully it will run right with the new gasket.
 
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twofast4u

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do you think maybe it could be a bad gasket? Not accord related, but the intake manifold gasket on my KA24 altima went, which caused the car to run really rich. After a few weeks i found the problem, replaced the gasket and all was well.

Thanks
 
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