CreamPuff

Hey S2KI,

I own a 2007 AP2 with 52,000 miles on it. A short while over a month or so ago the car seemed to idle rough but it wasn't very consistent and wasn't bad enough for me to make much concern about it. After a while I drove the car more frequently and the car's idle is really rough. It idle's at about 750 rpm and it's almost as if the car is pulsating. I don't drive the car everyday for I have other vehicles which is why it took so long for me to notice it. The check engine light is also not on and I just took the car in and got all the belts, oil, etc checked just before this happened. I was wondering if you guys had any idea what could be the issue. The car seems to have close to the same if not the same amount of power it did before this started happening. The best way I could describe it though is that it doesn't feel as finely tuned as it did before and it's almost like there is a leak of power somewhere. Any suggestions would be greatly appreciated, thanks!

- Matt

Ap2sant

A few things can cause a rough idle , let's see fuel delivery , insufficient fuel pressure ignition coil packs spark plugs vacuum leaks stuff like that man check your plugs

wineboy

I also have a 2007 AP2 and encountered the same symptoms right around the same mileage you have now. It got to the point where the check engine light came on. I brought it to the Honda dealer and according to the head mechanic, I needed a valve adjustment. I got the valves adjusted and it went away. According to the Honda mechanic, we need to get the valves adjusted every 30,000 miles. Whether this is true or not, the symptoms went away after the adjustment.

Greg W

A couple easy checks...
1. Get some carb cleaner and clean the IAC valve (idle air control valve), then check it out.
2. Look for disconnected vaccuum lines around the intake (driver) side.

Hope this helps...

CreamPuff

Update on the thread:

I took the car to my personal mechanic and found out that my first to cylinders have low compression. They are running at about 75% compression. I have no check engine light on. The mechanic then ran a compression test to see where the compression was leaking and it turns out I have a leak on my exhaust valve. He said the valve was already pretty tight and he tightened it up a little more maybe giving me an additional 5% compression. My warranty just ran out and I have opened a case with Honda USA to see if they will cover the problem. My mechanic estimated the fix to be $1,800 - 2000 so this is why I opened a case with Honda.

If Honda does not cover the valves I will be modifying the vehicle. God speed.

THanks for the tips guys, greatly appreciated.

NoTorkS2k

I've got 38% compression loss in cylinder 1 only. Rest are perfect. And the culprit... .drum roll. . . . . leaky exhaust valve(s)! I too did a valve adjustment, and the idle got smoother and it didn't die nearly as much. But the real problem still remains! Time to pull the head!

CreamPuff

Damn. My car is about to be finished and is in the shop right now. Honda USA said they would cover all parts cost and I have to cover labor up to $800. Apparently as they were pulling the valves my header was bad too and they bought a new header for the car... I wonder what it could be that could cause all of these problems. The car only has 52k miles on it...

How many miles are on your lil' guy?

I'll help you pull the head.

NoTorkS2k

I've got a MY00 with a fresh f22 in it. Only about 10k miles. But I'm boosted, and had a spark plug back out on me. So I already know what caused it. But I also had a cracked exhaust runner from cylinder 1 now that I think about it. Weird coincidence.

s2000maniac

Why would the header get header get messed up at such a lower mileage?

9grands2k

I just had the same thing happen to me. I'm also boosted and running a greddy kit. It looks like the spark plug was loose and then blew out taking the last few threads from the head with it. How did you fix yours? Any insight would be much appreciated. Can you try retapping the head without taking apart the engine?