[SOLVED] No power, enters limp mode on acceleration

yeah i definitely messed up, I must've been at TDC of the wrong stroke. I had seen that the best way was to connect the gauge and crank the engine until pressure would register indicating the compression stroke, then go until it stops adding pressure and go back a little bit
Guess I messed up, now my VC has 2 round bolts, don't ask me how someone managed that. I'd need to get new bolts before attempting to somehow get them off.
Is there a way to do it without removing it? I know that having a wrench on the crank while adding pressure is dangerous incase the crank rotates, but there should be another way?

 

Two things. One it's bad to try and turn an engine backwards cause you can cause slack in a chain/belt and make it jump time. Two if you try and do it via the compression tester method you can either go past TDC or be on the wrong stroke.

Just pull your valve cover. Buy some strip sockets to remove the rounded off bolts. They are M6x1.0 thread pitch for reference. So take one good one out and go to Lowes, Home Depot or whatever it is y'all have in Canada and buy some replacement ones which should only cost you a dollar or two.

If the bolts don't have a washer since the head has a washer base built into it then be sure to get a washer or two as well.

 

I used a big ass ratchet, appropriate socket on the crank and some fucking gusto. Also had a long screwdriver in the cylinder to tell when it was nearing TDC. Could use a timing pin for 1 and 4 but 2 and 3 you kinda have to eyeball.

 

So if I just use a screw driver, how would I know when it’s on the compression stroke and does that really matter as long as I’m at TDC
This would be much easier, the less time outside the better, it’s cold out here

 

if you're at TDC and cylinder 4 isn't holding any pressure, then cylinder 1 should have both valves closed. Same thing works for 2 and 3; one is open, the other should be closed.

 

The way I was taught how to find it is to put a small piece of tissue paper or something like that over the spark plug hole and when you get it turned to the compression stroke it will blow the paper off or move it noticeably

 

It's easiest to have someone watch while you turn the engine by hand via the crank bolt. I mean.... I had my 5 year old tell me when it moved haha Then stick a long ratchet extension in there or whatever you got like that and crank it up until it stops moving up and you're TDC.

 

@L337TurboZ is a professional and I am not so I'm sure removing the valve cover is a good idea but I didn't when I used this method. It gets you very close to tdc.

Like Enki said as well, your #1 and 4 cylinders are at TDC at the same time and the #2 and #3 are tdc at the same time too so you should only have to set it to TDC 2 times while doing the leak down test on our cars.

Cranking it until you see how hight the pressure goes for each cylinder is just a compression test not a leak down test. Compression test usually comes first and if something is low or off then the leak down is performed to find the exact issue like leaking valve or broken ring via excessive blow by and that type of thing.

 

So my compression is good but I'm just doing this to double check i guess
i definitely messed up tho because i assumed that because 1,3 and 2,4 moved together they would both be at Compression stroke TDC together so I didnt move anything just tested 2 then 4. I realize now that only one cylinder is on its compression stroke and the other one is exhaust stroke, so i definitely messed this up tho lol but that's how we learn right
So tomorrow ill set 1 at TDC and then redo everything properly with all of your suggestions, does it matter if I take all the spark plugs out at the same time?
I will also disconnect my DP tmr, its supposed to be dry and be 5 degrees woohoo

 

I usually remove the valve cover cause in the end it saves me time finding when the valves are fully closed instead of guessing.

If you do the leak down test you're listening for air leaks and checking for pressure drop in a cylinder. Having a valve cover off is the same as removing the oil cap or dipstick to listen for airflow into the crankcase.

Is it really necessary? No. I'm just lazy and get paid flat rate so I try and do things as quick as possible. If I have to spend extra time finding TDC compression stroke then that's money lost out of my pocket. To me it's easy to use my electronic ratchet to zip a bunch of 10mm bolts out and verify which cylinder is where in it's position/sequence.

 

Hey guys, I was going through some videos and this is when I first installed the cpe dp. Do you guys hear the choking at the beginning, I’m not sure if this is helpful?

 

No, it's still 4 times; you still have to reset to TDC on every cylinder to test them all.

This is completely wrong. Re-read what I wrote or better yet watch a video on how inline 4 engines run (and that one racing motorcycle doesn't count).

Why would it?

IIRC they are 8mm and there's a torque spec for them but I'm going to pocket this valuable knowledge you've dropped in the thread for later; makes perfect sense and isn't tough to do, since the TMIC would have to come off anyway. Do you torque them back down when you put it back on or just goodentite?

 

Yes Enki i understand it now, i was just saying what i thought before but I have since learnt that I was wrong

 

Yes sorry Enki and thanks for correcting me. They stroke together though right just one is on compression and one is not right?

 

No need to apologize, and yes. Look at my sig image, it's the firing order of our engines; each pixel of width = 1 degree crank rotation. You can probably figure out how they line up from there.

 

I never really torque valve covers to spec unless they have some weird design or are specified in a manual that they require torquing or damage can occur.

98 percent of the time I just run it down with my electronic ratchet and then double check how tight they are with a 1/4" ratchet. I'm not saying run it down and let it go 2-3 ugga duggas but enough that they all contact, the gasket isn't rolled or pinched, and then just tighten it up with a regular ratchet.

 

So disconnected my muffler and it didn’t change anything, I didn’t even need to drive it I can tell just by revving it, here’s a video and these revs I’m putting my foot to the floor and it only goes up less then a thousand rpm

going to reconnect go for a drive to warm it up then do leak down

 

Why would leak down be so shitty with decent compression?
So I redid the test and made sure I was at tdc of the compression stroke and my god cylinder 4 i don’t even know how it’s possible but 72% leak down and it was all coming out of the oil cap
Cylinder 1-8%, cylinder 2 55%, cylinder 3 18% and cylinder 4…..72% wtf
Idk guys I don’t even know how it would run with these numbers, and I made sure I was at tdc and it was coming out of the oil cap on every cylinder
Doesn’t make sense to me, I also made sure my compressor was giving more than 120psi to the tester. Anyways here are the pictures and a video for cylinder 2

 

Two different tests to measure two different things.

You did rotate the crank to make sure each cylinder was at TDC when you tested them correct? If so, the rings/ringlands are probably fucked, which is why it was sold to you and not kept; I'll have to go check the history of the thread to refresh my memory a bit.

As long as the engine can give the pistons even a small push it will idle. Sounds like you're probably slightly worse off than I am right now.

Congratulations on your new built engine!

 

You can have good compression but poor leak down. If there is a bad valve seat or burned valve face you can have it leak down a lot. The engine will spin up quickly and make compression but it won't HOLD the compression. That's the difference.