Had compression test done...

Hey All,

Had a compression test and 'partial' leakdown test done on my 05 Legacy GT. Its been stage 2 (etune) most of its life, max 18psi or so. I dont track the car or abuse it really, its mostly a daily driver to and from work. Might attack a on/off ramp here n there or give it some extra go pedal here n there.

Compression test showed the following:

1. 135

2. 58?/140(hot)

3. 135

4. 95/120(hot)

The shop was supposed to do a leakdown on all 4 cylinders but apparently only did the 4th due to some 'misunderstanding', the results were 15-20% for a few tries.

Obviously cyl 2 and 4 have issues, but cyl 2 seems to clean itself up when warm. Cyl 4 seems to not reach what it should at all and with that leakdown, im guessing there is something really wrong there.

Any thoughts of whether its valves or piston (ringlands) for the 2 'bad' cylinders? If it is a valve issue over a broken piston, do any of those valve cleaning services actually work? Stuff like seafoam or whatever the dealership claims they do in their fliers.

Seafoam is a cheap thing that may help.

Tell us why you decided to have the test done, did you have something that made you thing something was wrong ?

How did the car run before ?

Seafoam is a cheap thing that may help.

 

Tell us why you decided to have the test done, did you have something that made you thing something was wrong ?

 

How did the car run before ?

I had the test done as a checkup on a 110k mile car really. It was going in the shop for some other work and figured a health check would be a good idea.

I believe the car runs good. I thought it burned some oil but apparently I had a pretty bad oil leak from the oil pan (reason it was in the shop). Dont have smoke out of the tailpipe, gets the same gas mileage it always seemed to have (about 20-21 combined). I think it might idle a bit low, or is just not as smooth as it used to be during idle. Just had some groupN motor mounts installed so that kinda magnifies it now. Seems to spool fine and cruise well.

I'll let others who have a lot more experience guide your way. But to me given there are a problem with two cylinders on the same side of the engine I would think there's something in common with them which results in the lower numbers.

head gasket maybe?!

Compression test showed the following:

1. 135

2. 58?/140(hot)

3. 135

4. 95/120(hot)

 

The shop was supposed to do a leakdown on all 4 cylinders but apparently only did the 4th due to some 'misunderstanding', the results were 15-20% for a few tries.

This seems really strange to me because generally when you do compression/ leakdown test, that means that you do all four cylinders, every time. This allows you to compare numbers between cylinders and find out if it is leaking into the exhaust or through the piston rings themselves. IMHO, if you paid full price for a leak down test, you got ripped off hard.

In most cases, the leakdown results from cylinder 2 would be the key to determining what your issue is, so its really hard to say without those results.

Drive it...stop trying to find problems.

Have you replaced the O-rings at the intake to TGV's ? The new larger orange ones seal much better in cold weather.

Has the car always been on the stock MAP ?

This seems really strange to me because generally when you do compression/ leakdown test, that means that you do all four cylinders, every time. This allows you to compare numbers between cylinders and find out if it is leaking into the exhaust or through the piston rings themselves. IMHO, if you paid full price for a leak down test, you got ripped off hard.

 

In most cases, the leakdown results from cylinder 2 would be the key to determining what your issue is, so its really hard to say without those results.

Yeah it sounded really strange to me and thats why I asked them what happened. It was an issue with the work order not getting marked for a leakdown which isnt generally included in their standard compression test and the tech did it just because of the low number. But this is their words, it still may not be the whole story.

They offered for me to come in and get a leakdown done for free.. but im going away for 2 weeks so it wouldnt be until then, and probably when I have something else for them to fix.

About the headgasket.. I would think they would have brought that up as a possiblilty after doing the compression test and seeing the plugs and stuff right? I haven't had any over heating issues and they recently (9 months ago did a coolant swap when I had my timing belt done, so unless its really recent, I dont think thats it.

you might want to remove the oil cap and see if it blows any smoke from the filler when idling (which would be another indication of broken ringlands). hopefully you can rule that out!

Yeah I just read about that test.. ill try that soon.

Drive it...stop trying to find problems.

 

Have you replaced the O-rings at the intake to TGV's ? The new larger orange ones seal much better in cold weather.

 

Has the car always been on the stock MAP ?

I had the orings done in the last year or 2 with the orange ones. Was having issues on cold mornings till I had that done.

Car has been on a custom etune for most of its life. Back from the TDC tuning days. Always meant to get a retune but then got stuck into the needing to buy a new accessport to get a tune and that kinda stopped that since I always felt the car ran great. I know open source tuning is an option now, but being that im unsure of the health of the motor, I dont want to put it through the stress of a dyno or etune unless I knew for sure it was causing issues.

Car has been on a custom etune for most of its life. Back from the TDC tuning days. Always meant to get a retune but then got stuck into the needing to buy a new accessport to get a tune and that kinda stopped that since I always felt the car ran great. I know open source tuning is an option now, but being that im unsure of the health of the motor, I dont want to put it through the stress of a dyno or etune unless I knew for sure it was causing issues.

Very Smart^^ You never wanna do a new tune without doing a full physical first

IMO, start with that complementary leak down. If they offered it for free, capitalize on it before the offer disappears.

that's good that there's no smoke. it's an odd sensation, under normal conditions, the air "pulsates" out of the oil filler neck. it's hard to tell which direction the air is moving, but it's actually both directions.

do you get the sense that it's just pulsating like that? or is the air clearly just coming out?

that's good that there's no smoke. it's an odd sensation, under normal conditions, the air "pulsates" out of the oil filler neck. it's hard to tell which direction the air is moving, but it's actually both directions.

 

do you get the sense that it's just pulsating like that? or is the air clearly just coming out?

Pulsing for sure.. To the beat of the exhaust basically.

If you've had the car for a long time,you don't have any head gasket issues, it runs well.

When I had my wagon dyno'ed at 142,000 miles I didn't bother with all that. I owned it since new, it ran will, never had any issue until the turbo went. I knew the car well. It did fine on the dyno.

In your case, I wouldn't worry about that test.

You seem to know your car pretty well.

Sounds like you have a AP v1 not version 2 ?

If you've had the car for a long time,you don't have any head gasket issues, it runs well.

 

When I had my wagon dyno'ed at 142,000 miles I didn't bother with all that. I owned it since new, it ran will, never had any issue until the turbo went. I knew the car well. It did fine on the dyno.

In your case, I wouldn't worry about that test.

 

You seem to know your car pretty well.

 

Sounds like you have a AP v1 not version 2 ?

Yeah I have the OG accessport v1. My next worry is the turbo, which I had planned on replacing with a vf52 and getting tuned of course.

Where do people seafoam their cars when they live in a neighborhood that wouldn't like it to much if you sent a cloud of smoke in somebody's direction? Empty parking lot somewhere? Or is the method of adding it to a tank of gas good enough?

Is Cobb still doing the trade in for V1 ? I did that years ago.

I dont think so and I dont imagine them giving me much for it if they did. Could always fine a used one if I really needed one, but I dont think a new dyno/etune is in my near future.

So wait, when they did the leakdown on #4, did they tell you where the air was escaping?

The guy said "it might be dirty valves". If opening the oil fill tube and seeing smoke is absolute proof of a cracked ringland, then maybe he is right. Maybe a burnt valve?

I hope your still driving the car and not worrying about that botched test.

I agree with this,

that's good that there's no smoke. it's an odd sensation, under normal conditions, the air "pulsates" out of the oil filler neck. it's hard to tell which direction the air is moving, but it's actually both directions.

Main thing is, no smoke

I hope your still driving the car and not worrying about that botched test.

 

I agree with this,

 

that's good that there's no smoke. it's an odd sensation, under normal conditions, the air "pulsates" out of the oil filler neck. it's hard to tell which direction the air is moving, but it's actually both directions.

 

Main thing is, no smoke

Have no choice but to drive it Its running fine thankfully.

The guy said "it might be dirty valves". If opening the oil fill tube and seeing smoke is absolute proof of a cracked ringland, then maybe he is right. Maybe a burnt valve?

Did the guy just think it is dirty valves, or did he specifically say air is escaping from the exhaust and/or intake valves?

I hope your still driving the car and not worrying about that botched test.

 

I agree with this,

 

that's good that there's no smoke. it's an odd sensation, under normal conditions, the air "pulsates" out of the oil filler neck. it's hard to tell which direction the air is moving, but it's actually both directions.

 

Main thing is, no smoke