Well, to make a long story short, I was boosting 8.4 pounds on Thursday when going from redline into 2nd gear, it seems that my clutch is starting to slip. The RPMs hung at 6500 until it finally grabbed, but at that point they shot up too quick for me to react in time. It hit 7000 rpm (redline is 6800), and I shifted promptly, only to hear a "Pop!" sound...

Well since then, the car is making a sort of gargling sound when I accelerate. It's hard to describe and very faint, but it wasn't there before. I have been driving the car like a granny after this, but I tried boosting for short bursts, and it still pulls, but to me it feels just slightly slower.

Anyhow, here are the compression test results that Jake (GSRwBoost) and I took tonight (thanks again, Jake)...

Cylinder:
1. 185
2. 180
3. 170
4. 190

Then we put a cap of motor oil into each cylinder, and these are the results:
1. 235
2. 215
3. 205
4. 230

The numbers could be slightly off due to the inaccuracy of the gauge, but these are probably pretty close. We think it could be something with the piston rings, but I'm not real sure. I invite anyone who knows anything about this to comment.
Thanks..

 

looks like your #3 piston ring mightve went out. try redoing the compression checks again to make sure

 

you cant hit the limiter on boost, thats what that pop was your car detonating, your ecu cuts the FUEL at redline, BLAMMMMOOOO. you need an ignition cut set and to bypass your rev limit if you want to drive off the limiter

 

Thise initial numbers seem just fine really. You *may* have a small headgasket leak between number 2 and 3, but side from that you have a maximum of about 20psi variation between high and low, and if I remember correctly, facotry maximum is 28psi variation, so I don't think you're in too bad a situation. Check the coolant for traces or oil, and the oil for traces of water and possible small metalic peices in the oil when you drain it, that'll lead you on if there's any ring or gasket damage. Is the car smoking abnormaly?

 

Before doing a head gasket, retorque your head. I know people have had that problem, of head bolts/studs coming loose. Check that they're torqued evenly first.

 

Your car is fine.

 

What about the fact that the pressure increased significantly in each cylinder after adding oil.. Isn't that a sign of blown rings?

The car doesn't smoke or anything...

What could be the explanation for the fluttering/gargling noise?

 

your car is fine, my motor has about 180-185 in each cylinder. As for the oil, it seeps into grooves in your cylinder wall and will make compression seem higher. For example, awhile back in my friends CRX he had no money to fix it after he melted all the pistons. So what we did was use an old set of pistons that I had laying around with the old rings and slapped them in his car. His cylinder walls were also slightly scored on the #3 cylinder. Well, needless to say it smoked like a hooker but it had about 180 psi of compression, even in the cylinder will all the scoring. Anyway, the point is that the oil test is pretty much meaningless and your motor is fine.

 

No, actually that's 100% normal. When you get a VERY low reading (like 150 or so) and you add oil and it shoots to very high levels, that's a confirmation that your rings have died. But in any case, when you add oil directly to a cylinder, compression will skyrocket.

 

I'm just a bit worried about cylinder #3 being about 10.5% lower than cylinder #4.....I have heard that a difference of about 10 percent or 20 psi means that there could be a problem. I might not have bad detonation, but I'm thinking that something happened to lower the comp of cylinder 3. From the factory, I don't believe they differ by very much.

And the noise the engine makes now leaves me a little uneasy. Why is there a gargling noise?! If my engine was perfectly fine, I wouldn't have symptoms like this... I might be wrong, but I'd like someone to explain this to me.. Maybe I'll bring the car to a mechanic just to make sure, unless you guys are positive that I'm totally okay.

 

I always go with anymore than 15% diff is a problem.

 

how bad is hitting the rev limiter in a turbo honda/acura???

 

I guess this tread right here answers my question about which type of limiter is better, fuel or ignition.

 

thats actually not bad... my compression test #s are 150-155!

 

There is another, easier way, of testing to see if that number 3 is causing problems. With the car at idle, pull the number 3 spark plug wire and see if the idle changes considerably, if the cylinder is firing right, the idle should change. If not, the idle will remain the same. But, like everyone else has already pointed out, there doesn't seem to be any problem at all with your compression readings.
That oil test is to see if your rings are what is causing low compression and if performed on a car with no problems will increase the compression readings. Say you had a really low reading on cylinder 3, like 100. You put the oil in there and the compression shoots up indicating that your rings are weak. If adding the oil doesn't chage anything, then the compression leak is somewhere else, valve, head gasket, hole in the piston, etc.