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Got A Compression Test Done Today

Fujiwara

By Fujiwara,
in Engines & Forced Induction

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Fujiwara Proficient

Fujiwara

Posted
Posted (edited)

Here is the WHOLE story.

Purchased a Skyline R34 GTT from E&M Unique Motors 3 weeks ago *** Not flaming them so i don't see why i can't mention the dealership ***

I had it inspected by Stateroads before i took delivery and i also went over the vehicle and had it for a test drive.

1st issue - Took it for a dyno run at CRD. Was pulling 110kw@tw. Was an issue with the boost controller not being set right so they fixed this and now it's running 200.5kw@tw on 12psi.

2nd issue - Clutch release bearing was stuffed. They took the car in and replaced the clutch and machined the flywheel free of charge. Although i had to pay for a hire car...

3rd issue - Went to Advan today and got the compression test performed.

Cylinder 1 - 175

Cylinder 2 - 170

Cylinder 3 - 175

Cylinder 4 - 170

Cylinder 5 - 75 <--- WTF!!!

Cylinder 6 - 170

The guys at Advan said that it could be something in there like dust etc...unlikely but it could.

Also said that it could be the ring not sealing properly or the piston has worn out.

Advised me to drive it off boost and to get it checked out again at E&M.

Called E&M and advised them of the issue.

The first thing they asked was "is it idling rough? Is it misfiring?"

Advised them that it wasn't and they said "no need to bring it in".

I insisted on taking it in and he told me to call next Monday to book it in.

So was the guy trying to not do the test because he owes me new pistons or a new engine?

Or is he right? ie. no misfiring and no rough idle = engine ok?

POST EDITED

Edited by Fujiwara
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Cubes Grand Master

Cubes

Posted
Posted

So it has warranty?

If thats the case definitely bring it in. Say you've had it compression tested and cylinder 5 has shown up as having issues.

Regardless if its running smooth or not missing if a cylinder is down on compression it has issues and should be sorted under warranty asap.

GGG Proficient

GGG

Posted
Posted

Hi

Overall it does not sound right, check out the warranty conditions. They may only have to cover you for 1 month and thats why they are stalling. Check with governing departments or the car yards warranty company.

good luck

Cubes Grand Master

Cubes

Posted
Posted

Yep drop it in ASAP and have them sign a statement stating when the car has been dropped off and what the problem with it is.

Attach a letter from Advan stating the compression test results and say to the workshop it is to be fixed under warranty.

Don't let them stall and push you around; I've been there and done that and learnt the hardway. :dry:

If they state they can't get to it until x date still leave the car there as if that date is after the warranty has ran out your out of luck.

writeoff Mentor

writeoff

Posted
Posted

If you think the company is deliberately stalling you to avoid having to pay for any repairs then write a letter to them stating what the issue is, where it was found and by whom. Then post this as registered mail IMMEDIATELY. This then becomes their first formal notification and they have to sign for it to acknowledge they they received the correspondence. Do not delay doing this as it may be crucial in the worst case scenario where you end up ahving to take them to court. I'm not trying to scare you but it takes very little effort on your behalf, costs stuff all, and can save you heaps of $$$$ in the future. The one thing that I've learnt about our legal system is if it doesn't exist on paper then it simply doesn't exist.

benl1981 Grand Master

benl1981

Posted
Posted

thats odd. i thought you would have noticed if the comp was downs that low on 1.

And I wouldn't have thought you'd get 200rwkw out of it at 12psi.

Pays to get it checked out though.

Maybe repeat the test..at the place that are going to do the warranty. Make sure you are there and check they reset the gauge before they put it on the faulty cylinder

Fujiwara Proficient

Fujiwara

Posted
  • Author
Posted (edited)
Isnt 170-175 too high for a turbo engine? Shouldn't it be around 150?

Are you sure u didnt buy a non turbo?

Definitely bought a turbo. Has the turbo rush. Guys at Advan didn't say anything about being too high. They just said it's heaps healthy.

Also, fastened the VIN and it is a turbo

post-38029-1184016955_thumb.jpg

could it be a screwd gasket??

Can someone else comment on this?

And can a head gasket cause just one cylinder to be down by 100psi?

yeah. is it a 10year old car?

yeap...10yr old car.

it wouldnt hurt to do a leak down test while you are at it, might give you a little better insite?

was performed when i had the prepurchase inspection.

No issues. Pity they didn't perform a compression test..... :thumbsup:

yeah. make it formal. or simply say yes it is f**ked and running like shit.

Definitely sending an email today (better to track with email)

unusual. the turbo will pop before the motor

How so? And how will i know IF my turbo is about to go kaboom?

thats odd. i thought you would have noticed if the comp was downs that low on 1.

And I wouldn't have thought you'd get 200rwkw out of it at 12psi.

Pays to get it checked out though.

Maybe repeat the test..at the place that are going to do the warranty. Make sure you are there and check they reset the gauge before they put it on the faulty cylinder

So 100psi down on one cylinder would make it impossible for me to get 200kw at the rears?

The guys at Advan say that it COULD be a one off issue. They retried the same cylinder about 4 times though. They said once i start driving around, any "dust" in there could go away and the rings could seal properly IF it was that issue.

Can anyone else comment?

I have the dyno graphs here...excuse the crap quality...taken with my phone

post-38029-1184017969_thumb.jpg

post-38029-1184017931_thumb.jpg

Edited by Fujiwara
BHDave Grand Master

BHDave

Posted
Posted

If you had a leak down test done pre purchase and it was good then you may want to read up on what it is you tested before jumping the gun based on a compression test result.

You will not make 200rwkw on 12psi if one cylinder is bleeding off pressure.

I suggest 3 possibilities, 1) it's a dud compression test, 2) Your initial leak down test was dodgy, 3) you've broken the car between your initial leak down test and the later compression test.

If you take the car back to E&M to be checked and it shows all good, you will be charged for it. If it shows up bad, then make sure you are familiar with your warranty conditions because you had it independently tested, and it was good when it left the lot. You've played with it in the mean time. I think you will lose if it goes before a judge.

Not trying to be harsh, but seriously, find out what you tested pre purchase before going any further.

Cubes Grand Master

Cubes

Posted
Posted

Im with Dave. Now that you say you had a leakdown prior to purchase and all was good there's not really much you can do.

Have another comp test done; chances are the test was a bit bogus. How many times was each cylinder tested, should be seperately tested at least twice if there's any funky readings.

If it has lost compression all of a sudden it would indicate detonation and smashed ring lands in that cylinder.

It is making 200rwkw on the stock ecu with 12psi so really it is quite highly strung. That small SMIC would heat soak fairly quickly after a hard run, keep your boot in to it and it will rattle its head off. The knock sensors only protect the motor around peak torque, high rpm the ecu ignores it.

mad082 Grand Master

mad082

Posted
Posted

also if it was that low in compression in 1 cylinder you would be using a touch of oil and it would blow a bit of smoke when you got into it a bit. get someone to follow you and then give it a good bootful through first and second. if there is no sign of smoke it make be a dodgy test. if it does blow white smoke then the test is correct.

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