origamy

knock sensor and it's wiring is ok, where else should i look?

origamy

Bought myself a new compression tester, and did compression test once again. Results:

DRY:

Cyl. no.1 first try - 200PSI, second try - 200PSI
Cyl. no.2 first try - 190PSI, second try - 195PSI
Cyl. no.3 first try - 190PSI, second try - 195PSI
Cyl. no.4 first try - 200PSI, second try - 200PSI

WET:

Cyl. no.1 - 220PSI
Cyl. no.2 - 210PSI
Cyl. no.3 - 210PSI
Cyl. no.4 - 220PSI

Any comments?

afnan

I guess they have to be near 173 PSI i suppose.

See I am interested in this thread as i faced the same issue. My fuel line pressure was in normal range at idle but car bogged down. What i did was completely blocked the return line temporary which solved the problem. Then it came to be FPR.

origamy

210PSI when new, manual states

holmesnmanny

those numbers are fine

ej7attack

I would like to jump in and add my .02 but like stated before could be a fuel delivery issue.
it seems as if you have done plenty of testing on the electrical components but not much on the fuel except for pressure.
fuel pressure can be fine but injectors or regulator could be faulty. if you can source a noid light check the injectors for electrical current. then pull them out of there home and check for carbon build around the nozzles.
have you changed the fuel filter?
partially clogged filter may inhibit fuel flow under load.
again if you are confident it has nothing to do with air, spark and sensors with no cel, go with fuel delivery.

origamy

Well, injectors are clean and o.k., no carbon build up whatsoever around the nozzles, they do spray fuel. Fuel filter was changed recently. Fuel pressure regulator was tested and is o.k. too...

afnan

This thread is turning into suspense digest. Fuel, Air, Spark and Timing is everything you need. so probably something is not right.

origamy

Did two videos on cylinder 2 compression test. Take a look, as I understand sometimes on the first crank it does not build up 100PSI, as it normally does. Other 3 cylinders always make ~100PSI on the first crank

Normally it goes like this:


But sometimes it goes like that:


I did not notice this happen on other 3 cylinders. What could be the cause?

afnan

Try using scope to see inside and condition of valves and piston

origamy

Well, I don't have a scope to do that. But I've noticed one more thing. When performing a power balance test (by removing spark plug wires one by one at idle) when cylinder no.2 spark plug wire is removed - engine dies almost instantly. When spark plug wires are removed from cylinders 1, 3 and 4 - engine just starts to shake more, but continues to run. Tried a few times, result is always the same. Maybe this says something? Maybe intake valves on this cylinder are possibly leaking? Or exaust is somehow restricted on this particular cylinder?

skhell

Can't understand those symptoms...
It would make sense if there was no change in idle when removing a wire plug, meaning there was some problem with that cylinder.

Removing that wire, and the engine just dies, it could mean there is a problem with all other cylinders, except that one... Have you tried another set of spark plug wires?

skhell

You can try the following: get a water bottle sprayer, go to a dark place at knight, preferably with no lights at all, and spray a little of water over the spark wires and distributor cap.

If you see same sparks(arches), it means your wires are not in the best conditions.
On the other hand, if you don't see any thing weird, it doesn't mean that they are in good condition...

origamy

Plugs, wires, cap, rotor, coil & ICM are new. Read older posts please

skhell

Damn, I'm out of ideas :s
I guess that you could try do same test with the fuel injectors, removing the plug of each one, one at the time...

afnan

What is the update? did you managed to get it resolved ? what is your short term fuel trim values?

skhell

How can you check the fuel trim values?

origamy

Recently I've changed fuel injectors to no improvement. Now about fuel trims. When driving, STFT changes fast all the time, range is wide. LTFT is about 7 when cruising at 100km/h. When car is stopped, results are:
At idle (750rpm):

STFT: from -5.47 to 1.56 (fluctuates all the time)
LTFT: 0 to 0.78 (remains almost constant)

At 1500rpm:

STFT: from -9.38 to 10.16 (fluctuates all the time)
LTFT: -0.78 to 0 (remains almost constant)

At 2500rpm:

STFT: from -13.28 to -5.47 (fluctuates all the time)
LTFT: -0.78 to 0 (remains almost constant)

At 3500rpm:

STFT: from -10.16 to 2.34 (fluctuates all the time)
LTFT: -1.56 to -2.34 (remains almost constant)

Car drives me mad half a year already. I guess the problem started after some high speed driving (@205km/h). Vibration at idle, jerking when accelerating/decelerating. I remember one thing. When I tested compression for the first time after the problems started, compression in second cylinder was just 8.5BAR, other 3 were about 14BAR. Maybe that was a mistake or something in measurement, I'm not sure. Then I added some oil into that cylinder, and compression became 13.5BAR. Then drived the car for a few months, and tested compression again. It was cyl.1 - 14BAR, 2nd-13.5BAR, 3rd-14BAR, 4th-14,5BAR with no oil added. Tested a few times after that again, on hot and cold engine, results were the same. But somehow I still think that there is some mechanical issue with cylinder no.2. It's spark plug is whiter, and when sparkplug wire is removed from cylinder 2 engine dies almost instantly. Engine consumes about 0.5l of 5W30 grade oil every 1000km, but there is no smoke at all. And no oil on the ground. I guess that's because catalytic converter still does it's job well (not for long with such a rate of oil consumption, I guess). Most probably I'm going to install new long block soon, because I don't know what else to test/check. Everything leads me to something mechanical.

skhell

You get those fuel trims through the OBD connector, right? Mine doesn't have one, would like to check them out, just as a curiosity...

afnan

Your values are in normal range. However they should not cross 10 either on + or -.

Please answer following.

1. Did you ever Changed or adjusted Fuel Pulsation Damper?
2. What is your ignition timing at idle. It should be near 12 degrees.

origamy

1. Never
2. 12 degrees

Anyway - new long block has arrived. Has 80.000 miles on it. Two weeks later it will be installed into my car and I hope that I'll forged about 0.5l of oil every 1000km, jerking/hesitation and rough idle

skhell

What do you mean by long block?

origamy

skhell

Nice!

I see that you are missing the knock sensor, don't forget to install it before you put the engine in the car ;-)

origamy

Yeah, sure