[SOLVED] No power, enters limp mode on acceleration

[Enki]

That doesn't add up. Freek knows about this issue, correct? What has he said about it?

 

[chris' speed 3]

i feel like I need to do an update now that i've learnt a lot more since this issue first started happening.
So it stumbles a little bit on startup ill attach a video. but besides that from -11,-2 psi it drives like nothings wrong and pulls normally with normal power. But once I give it a bit more load it starts to Buck and make a loud vacuum kinda noise and then the CEL starts flashing, AFRs also are more lean then usual
There are no codes besides p0300 which pops up consistently after the CEL flashes, sometimes a p0442 and a p0401(egr is deleted)
Also ever since the downpipe install it rattles on decel, most likely irrelevant but worth noting

Compression is 140 in cylinder 4, the rest are 160-180

So now my questions, if cylinder 4 was causing the issue would I get a p0304?
If the issue seems to happen when boost kicks in, does cylinder pressure increase in boost or is it the same pressure just at a faster RPM
Also compression in cylinder 4 has been 145 since June
@Enki @StreetSpeed6 @L337TurboZ @Awafrican

That doesn't add up. Freek knows about this issue, correct? What has he said about it?

Im still waiting to hear back from him

So here’s a video of
-the startup
-the issue happening
-cylinder 4 compression test, dry and up to temp
-the rattle

 

[Enki]

None of those videos show anything that seems out of place to me. Was the issue on the OTS tune that "had the same issue" the leaning out AFR issue or some other issue?

 

[chris' speed 3]

None of those videos show anything that seems out of place to me. Was the issue on the OTS tune that "had the same issue" the leaning out AFR issue or some other issue?

Not exactly sure what your asking, Stage 1 tune that I flashed on had lean afr and my main issue that the engine bucks and chokes up when adding load like all tunes ive tried
Except for my last freek tune seems to have slightly better AFR, still lean however

 

[Easter Bunny]

Is your battery fully charged? If my car sits and the battery gets weak it runs like ass. Never got a cel but same stumble on startup

 

[chris' speed 3]

Is your battery fully charged? If my car sits and the battery gets weak it runs like ass. Never got a cel but same stumble on startup

I actually thought about this so i started monitoring battery volts and it stayed at 14 so i think its good

 

[Enki]

Not exactly sure what your asking, Stage 1 tune that I flashed on had lean afr and my main issue that the engine bucks and chokes up when adding load like all tunes ive tried
Except for my last freek tune seems to have slightly better AFR, still lean however

The engine is bucking because it's too lean to fire properly. If Freek tunes around this issue, when you do get it fixed the car will be undrivably rich.

 

[chris' speed 3]

The engine is bucking because it's too lean to fire properly. If Freek tunes around this issue, when you do get it fixed the car will be undrivably rich.

So what would cause that if there's no leaks? Fuel pressure looks good but is it possible its still a fuel issue?

 

[Enki]

If there's no air leaks anywhere, and the fuel system is fine (looks that way) or exhaust leaks letting air in (somewhat unlikely), then the only things left would be bad MAF sensor, wiring fault, ECU fault, or clogged injectors (probably unlikely because you said it runs pretty even until it starts bucking).

 

[chris' speed 3]

If there's no air leaks anywhere, and the fuel system is fine (looks that way) or exhaust leaks letting air in (somewhat unlikely), then the only things left would be bad MAF sensor, wiring fault, ECU fault, or clogged injectors (probably unlikely because you said it runs pretty even until it starts bucking).

How would I be able to test for those things?

 

[Enki]

Swap injectors and MAF with someone else. If it persists, probably wiring/ecu.

 

[chris' speed 3]

Swap injectors and MAF with someone else. If it persists, probably wiring/ecu.

If it is compression, why would it only be bucking under boost?
I have number from a cold, wet and dry for cylinder 4 from june and dry was 145 and wet was 180. So piston rings would be the problem here. How come its only noticeable under higher load, isn't the pressure in cylinder always the same it just revolves at a faster rate?
@L337TurboZ

 

[L337TurboZ]

Think of it like this. You have 4 2.3L bottles. You blow air into each of them at gradual rate. The first one holds up to 30 psi no problem. The second one does 28 psi fine. Third one does 29 psi fine. The fourth begins to leak air at 11psi.

You find that up to 11 psi it's ok but at 12 psi a pin hole starts leaking air out gradually getting worse the more air you try and force into it. You put some oil on the hole and it holds a little more pressure.

That's essentially what's happening with low compression and bad rings. In vacuum they're pulled against the cylinder walls through the PCV system. It's enough that it runs and is somewhat ok. But then you start building boost. Boost pressure is going into your crankcase now and bypassing the rings. The crankcase pressure builds and instead of being in vacuum it's now putting boost in behind the MAF sensor through the valves cover port. I bet if you didn't have that hose connected it would spray oil out.

Now I could be wrong. If your MAF/turbo inlet pipes have a bunch of oil residue more than a normal amount this is probably the case. Hell you could have a cracked piston, a broken ring, worn rings, worn block, bad head gasket etc.

Btw if the engine is burning any coolant even a small amount that moisture/water can cause a lean reading on the O2 sensor.

This is why you need to do a cylinder leak down test with a good leak down tester. 180 something on one cylinder and 145 on another is a big difference in terms of percentages.

I know you said 180 was the wet result but you also said you had 185 or something on cylinder one when it was dry. So if cylinder 4 is at 140 dry and cylinder 1 is at 180 that's a 40 psi difference. A 25% difference give or take.

 

[chris' speed 3]

Think of it like this. You have 4 2.3L bottles. You blow air into each of them at gradual rate. The first one holds up to 30 psi no problem. The second one does 28 psi fine. Third one does 29 psi fine. The fourth begins to leak air at 11psi.

You find that up to 11 psi it's ok but at 12 psi a pin hole starts leaking air out gradually getting worse the more air you try and force into it. You put some oil on the hole and it holds a little more pressure.

That's essentially what's happening with low compression and bad rings. In vacuum they're pulled against the cylinder walls through the PCV system. It's enough that it runs and is somewhat ok. But then you start building boost. Boost pressure is going into your crankcase now and bypassing the rings. The crankcase pressure builds and instead of being in vacuum it's now putting boost in behind the MAF sensor through the valves cover port. I bet if you didn't have that hose connected it would spray oil out.

Now I could be wrong. If your MAF/turbo inlet pipes have a bunch of oil residue more than a normal amount this is probably the case. Hell you could have a cracked piston, a broken ring, worn rings, worn block, bad head gasket etc.

Btw if the engine is burning any coolant even a small amount that moisture/water can cause a lean reading on the O2 sensor.

This is why you need to do a cylinder leak down test with a good leak down tester. 180 something on one cylinder and 145 on another is a big difference in terms of percentages.

I know you said 180 was the wet result but you also said you had 185 or something on cylinder one when it was dry. So if cylinder 4 is at 140 dry and cylinder 1 is at 180 that's a 40 psi difference. A 25% difference give or take.

So if i was to disconnect that hose from my catch can and see if its spitting oil out when I rev it into boost that would be a good indicator?
Also coolant level hasn't moved at all
No wet oil in the intake pre turbo but I do have catch cans for that, there is some oil in the IC piping but its always been like that.
Theoretically, of the boost is by passing the rings then coming out my VC into the post MAF port on my intake then this could cause the lean condition right.

Also yeah cyl 1 is 180 dry, I have a buddy that is in school to be a mechanic and I think he's Ana borrow the leak down tester this weekend and bring it over and well test it out

 

[L337TurboZ]

If you disconnect the hose you're going to run lean as it's an air leak. How fast is the catch can to pre turbo filling up?

You're also going to need an air compressor to use the leak down tester

 

[chris' speed 3]

If you disconnect the hose you're going to run lean as it's an air leak. How fast is the catch can to pre turbo filling up?

You're also going to need an air compressor to use the leak down tester

Last time i dumped it was 5-600km ago when this problem first started happening. Ill go check it after
For the air compressor i still live w my parents and my dads got a big compressor

 

[StreetSpeed6]

Last time i dumped it was 5-600km ago when this problem first started happening. Ill go check it after
For the air compressor i still live w my parents and my dads got a big compressor

I would say cap off the intake vc port and see if the lean condition is still there. I bet your bad compression is the culprit and it just finally got bad enough to actually cause issues.

My engine did the same thing but it boosted still it just was super slow and started leaving a cloud of smoke behind during wot

 

[chris' speed 3]

I would say cap off the intake vc port and see if the lean condition is still there. I bet your bad compression is the culprit and it just finally got bad enough to actually cause issues.

My engine did the same thing but it boosted still it just was super slow and started leaving a cloud of smoke behind during wot

Ill try some things out this weekend, ill plug that hose and the intake port and see if anything changes

 

[chris' speed 3]

I would say cap off the intake vc port and see if the lean condition is still there. I bet your bad compression is the culprit and it just finally got bad enough to actually cause issues.

My engine did the same thing but it boosted still it just was super slow and started leaving a cloud of smoke behind during wot

Mine still boosts and is slow only in boost, I haven’t noticed any smoke or excessive oil consumption

 

[chris' speed 3]

If you disconnect the hose you're going to run lean as it's an air leak. How fast is the catch can to pre turbo filling up?

You're also going to need an air compressor to use the leak down tester

So went out and emptied my cans
The one VC->intake is a Damond vented can, it had maybe 50ml in it after 500km it was also -0°c pretty much all of last week here at night so I’ve heard that increases the occ empty interval, it was also the lighter liquid in the bottle with some weird solid substance floating on top
PCV->IM is a sealed occ from mishimoto with a check valve to IM. It always has brown sludge in it. That’s what is poured ontop of the lighter color from the previous occ
All together maybe 150ml