Compression test results on Z22YH......

[Nik]

Right, was changing the plugs today, or going to, (silly ***** at Halfords have the wrong 1s listed ) and thought i would do a quick compression test to see what it was like and if it might have anything to do with my on going engine problem.

I dont know the firing order so will list the results in cylinder location i.e from left to right...

(190psi) (200psi) (230psi) (230psi)

Now i am aware that this indicates a problem as the range between them is so far out. But what sort of problem am i looking at??

[Nik]

Sorry, i got the results wrong after looking at the gauge again.

They were infact...

(190psi) (230psi) (200psi) (200psi)

[Nik]

Also, is it worth noting that after the 1st turn of the key, on the 2nd,3rd and 4th cylinder (again from left to right) it was making a "pop" noise.Only done it once on each test.

[Critch]

What did the plugs look like? What milage is car on? Im guessing no 2 could have a build up of carbon on piston crown.

Are you having other running problems?

[benny]

do you have a problem with your engine ? ...is it running correctly ? ...do you have any man lights on ......

[Nik]

The plugs were all a sort of light brown colour. Mileage on the car is 128k.

After having a look online, the general consensus seems to be what you are saying about the build up of carbon. How would i go about getting it off?? With an engine/fuel additive??

My running problem seems to be the car mis-firing under load, but its fine when feeding the power in slowly. If i was to plant the foot in 2nd gear, it gets to about 4k rpm then the EML comes on and the car mis-fires. Need to pull over, switch the car off, then re-start it for it to go away.

[Nik]

do you have a problem with your engine ? ...is it running correctly ? ...do you have any man lights on ......

Where do i start. lol.

I have a few threads up regarding my engine problem but no1 seems to have any ideas.

[benny]

have you checked the fuel system out is the high presh fuel pump ok is it giveing the correct presh ?...is it part of the regulator recall ? .....a missfire caused by another reason would give a low comprestion reading on the afected cylinder ....fix the miss and the comprestion will go back to normal ....what are they like after a wet test ?>

[Nik]

Problem started a few weeks ago benny.

To start with, the car would struggle to go, and had a mis-fire feel up to about 3k rpm, then it would pick up from there and pull all the way with no hesitation.

Then it was slowly getting worse. Now, it wont rev clean at any point in the revs if i was to plant the foot down.But it is fine when feeding the power in. The lower gears, 1st, 2nd, and 3rd seem to be the worse.

When stationary, if i was to quickly blip the throttle, you can feel it mis-firing, then clearing as the revs rise.If i was to feed it in till its over 2k while stationary, then floor it, it will rev fast and clean all the way.

Checked for fault codes when the problem 1st happened and it was coming back as the swirl valve flaps and the IAT sensor.

Done some live data with the car running and fuel pressure is 5000kpa at idle, then it rises when giving it some throttle.

[Nik]

Also, whats a wet test??