Well it was a nice day so went out and replace the spark plug. Also did a compression test following the repair manual instruction.

Compression was 1-170, 2-170, 3-175, 4-170. I believe the number is good but not sure.

The spark plug looks good but not sure either. I went ahead and put new ones in. Plugs are the BPR7ES. Is the car running lean? Do I need to use BPR8ES?

Any help or suggestions would be appreciated.

 

From what I've heard, those numbers are good

 

Any addtional comments/suggestions?

 

how u do the compression test?

 

evo use idriums not regulars, but if you wanted to run regulars you should have used ngk r5671a-8's another number for these is stock # 4554. they run great in a lightly moded evo

 

The BPR7ES look to be doing just fine for you.

 

I just remember that I did not go WOT when cranking for the compression test. Does this mean that the results are incorrect?

 

That will only help the numbers usually. Your numbers are good and the plugs look normal.

 

What is the problem with the car you are trying to solve?
Previously you asked about a disconnected hose at TB but never posted back about it.
Let's stick to a post and fix the problem.
Talk to me.

 

Thanks for the help. Not sure what's wrong with the car. I suspect a vacuum, exhaust, or boost leak somewhere. During cold start the idle is not constant and will fluctuate. Just need to pin point the location. There was a tear on both the silicone coupler on the upper BR intercooler pipe so I replace it with a thicker one but shorter in length (3" vs 4"). Not sure if it's leaking from there.

The disconnected hose that I was refering to is underneath the TB. There are two vacuum line. The one with the yellow strip is connected where as the one next to it is not.

 

Here is a picture of the service manual.

 

I just tore my car apart and as far as I can tell (pic hard to decipher) that hose should be connected. It is either EGR related or Evaporative emissions related. Either way it is a leak and the idle will do exactly what you describe. Stock cam vacuum at idle should be around 17 and about 15 or so with cams. Your Idle Air Control motor is trying to adjust for the extra air and then when it drops it backs out and raises the idle up again. It does this on many cars if there is a vacuum leak. I will go out and look at that hose to see where it went.

 

The one next to it has a blue strip on the bottom side and goes to the EGR valve (yellow does too). EGR valve is disc shaped part bolted to manifold under throttle body.

 

timzcat,

Thanks for your help. I tried finding out where that line went but could not. My guess was that it was a connection to the boost solenoid or turbo inlet but not sure. So both needs to be connected? Not sure where the one without the yellow stripe is connected underneath but the upper portion ends right where the pictures shows which connects to nothing and sits next to the one with yellow stripe.

Can anyone else confirm whether that line should be connected. If you look under the TB there should two lines. One with a yellow strip and the other next to it.

Thanks.

Two bov didn't work.

 

I can assure you that's where it goes. Only two lines that go over there.
Look at the EGR valve and you will see the line missing.