Speedfreack_198

Hi guys, Need help and expertise. I have an Civic si 2010 130k miles, bone stock no mods. Well it started a while back; only at a cold start coming to a red light literally down the street. Every thing works fine intel I push the clutch in and rpm needle just drops to zero. Oil and battery light comes on and literally I cant even tell it stalls out intell I try to give it gas. Well I have done my research on the issue but every thing that I see is to clean Throttle body, iac and etc....

Well I found a vacuum leak while back and I fix it. I clean both throttle body and Mass flow sensor (MAF) as well and also I did Idle relearn procedure and nothing change. It idles fine around 750-800 rpm and no surging at all at a stop.
Note this only does it at a cold start after it warm's up I feel like the rpm's is bounding around when I'm coming to stop(clutch engage) but never go's below 1000 rpm's (when slowing down) then 800 rpm's (complete stop).
I have done all the research I can; I came to a road block.
Note again please don't suggest cleaning IACV or TP this civic does not have IACV(electronic throttle body). Also TP is one component with the throttle body on the side. I really don't know if its a good idea to start opening that. lol I have notice oil in one of my vacuum hoses the one connects to valve cover head and air intake duct which the vacuum leak originated.
No cel ether. Here is my video I record as it does it. And i I upload to youtube https://www.youtube.com/watch?v=9xlTd1Wbtm8

dpetro1

do you have any CEL codes? even if the CEL is not on you might try scanning the ecu

Speedfreack_198

I don't know that. So it stores it? If so can AutoZone or O'Reilly can pick it up?

dpetro1

yes, if you don't have a scanner you can have a local parts store scan the ecu just to be sure

Speedfreack_198

Ok, just came back from AutoZone and no CEL or store it.

holmesnmanny

Have the spark plugs ever been replaced?

Speedfreack_198

Yes, I did it at 100k miles NGK type

97emsedan

Maybe have your throttle position sensor relay changed out. The part is about $50 USD and is easy to find ( engine bay fuse panel ). That might cure it.

holmesnmanny

Most parts are going to throw a code if they are bad. It's possible you have an exhaust leak and/or the oxygen sensor is bad, I would seafoam it to see if any exhaust leak from the exhaust manifold to the oxygen sensor and if no leaks then swap out the upstream sensor.

Speedfreack_198

Ok, updates still doing the same thing and I think it's getting worst.
Parts that I change and for misdiagnose

1. Idler pully
   
2. Tensioner pully

So now I’m leaning throws Mass Flow Sensor. I tried cleaning it and no change. I want to know if there was a way to test if it’s a bad. I saw a video in you tube a guy disconnect the sensor and car shut off, but he said if it is bad car would still run. Is that true? Anybody haves a better way of testing?

holmesnmanny

Sounds like you got this figured out all on your own.

Speedfreack_198

Well we will never man I literally total it this weekend RIP

DaveSi677

wow that is unfortunate!

bckasper3

I would check the throttle body or the idle control valve. It should be pretty simple to take them off and clean them with throttle body cleaner. I would also check to make your spark plugs are gapped correctly. I had this issue and I noticed the car idled low at close to 500rpm because the idle bypass valve was dirty. Cleaned it up and now it idles at a more typically 850rpm and fixed the issue. give it a try.

Ryanthegreat1

Hey, newb, this thread is 5 years old and if you read it you would know the OP totalled the car before bothering to resolve the issue.