When diagnosing engine misfires after a replacement, systematic troubleshooting using diagnostic tools is essential; the process involves checking for loose connections, swapping components like coils and spark plugs, and using smoke tests to identify air leaks in the intake system, which are often the root cause of persistent misfire issues.
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Porsche DIY novice engine swap - the first drive since replacing the bore scored engine!
Added:A couple of months ago, I saw this beautiful Malachite Green Boxster at auction.
I fell in love with the color of this car, and I really wanted to buy it.
But, there were a few issues.
Now, this generation of Boxster, especially the 3.4, is known for bore score.
And bore score usually has a couple of symptoms, both of which were on the list of problems with this car.
The first one is the engine was tapping.
And the second one was the engine was smoking. But, I thought maybe I could take a gamble on this.
Could the smoking and tapping just be because it hasn't been started for a while?
So, the car turned up.
Oh, no. And oh my goodness, did it smoke? And did it smoke and did it tap as well?
I was really worried at this point, so we took it to my friend's garage.
We got it up on the ramp, and we decided to look inside the bores, and this is what we found.
Yep, that's bore score, all right.
And there's also some weird kind of damage on the piston there. All of this meant that I would need to get a new engine.
So, I got one from eBay.
So, I got this engine and replaced quite a few parts on it, like the air oil separator, the rear main seal, the IMS seal, the water pump, the thermostat.
[music] And it came out looking pretty good.
So, we got the engine in and started, but there's a massive misfire.
So, in today's episode, we're going to try and find out what this misfire is, and hopefully go on the first drive.
So, welcome to another video on my Malachite Green Boxster. And yeah, in today's one, I hope to be driving the car and doing the first test drive, and maybe seeing how well it performs. But first, we do need to fix this misfire.
And to do that, what I'm going to do is check a few things. So, I think it could be something like a loose connection on a coil pack or on a sensor.
Or it could be an air leak somewhere, maybe around the plenums or AOS hose or something like that. And to fix this, I'm going to need to use a diagnostic machine. So, I'm going to use the Mucar 892 BT. Um if you do want to buy one of these after watching the video, I'll put a link in the description and here's the QR code as well.
But what I want to do is kind of go through, check if it's misfiring on a certain cylinder and if it is, I'll concentrate on those ones. And if it's not, then I'll start looking at some of the sensors, maybe seeing if there's like an air leak or something like that.
So anyway, yeah, let's have a look and see what the machine says and we'll get this fixed.
All right, so I seem to have a bit of a misfire.
So, what I'm going to do is see which cylinders are misfiring.
And I can select them all here. Um So now on this screen, I can see that a couple of cylinders are misfiring.
Let's have a look at this on a graph to make it a bit more obvious.
And now you can see the misfires going up on the graphs. So, let's take a look at why. I think what I'll do is swap over the coils and spark plugs and just see if that moves the problem around.
I did buy some brand new coils and spark plugs from Design911. So, I don't think it will be that, but we can take a look.
Just going through to see if we've got any codes here.
Park assist, I know about.
So, we don't have any codes. Let's change the spark plugs and coils around.
Well, unfortunately, the same problem is still there.
So, it's something else, but I think I can hear some air leaking somewhere. So, I'm going to get my smoke detector out and see if we can find the leak.
So, I think I've got an air leak. I'm going to get my smoke machine and poke it down where the air filter goes.
Let's see if we can find where this air leak is.
That's the air filter out.
So, I've got a rubber glove. I've cut the end off a finger.
I'm going to put this over where the air filter goes.
And then we're going to poke our smoke machine through into that finger.
And you can see here I stretch the end of the glove over where the air filter plugs into.
All right, so got some baby oil. Uh we're going to put it in here. This is a smoke generator.
And what this will allow us to do is it will blow smoke into the glove.
And then that smoke should go around the whole system and hopefully we'll see where there are any leaks.
Where the smoke comes out.
Yeah, there we go. Smoke coming out there.
See where this is coming from.
So, I can see from the camera on my phone that the smoke is coming from the rubber gasket on the end of the plenum.
So, I think this is our smoking gun, quite literally.
So, the problem is here with the rubber gasket on the end of the plenum there, it's actually not over the inlet manifold enough. So, there's a gap at the bottom, quite a big gap. So, what I do, I adjust it around and then tighten everything up and we should be good to go here. Hopefully, no leaks.
So, while I've got everything in bits like this, I'm actually going to replace the tube to the AOS. Now, I did notice a split in this which I did repair.
But, for the price of a new one, I thought it'd be better to replace it and do everything properly.
So, let's get that replaced as well.
Yeah, so that was my temporary repair.
That's never going to last, so >> [snorts] >> See, it's broken there, isn't it?
So, let's get a new one on.
Now, this was a really fiddly job and I had to loosen the inlet manifold, but I got there in the end.
Right, so I've just got to clip the hoses back on now.
And then we should be able to run it.
Now, as well as the hose I replaced, there's another hose which goes from the air oil separator to the inlet manifold.
So, let's get that one on and we should be ready to start it.
All right, last one.
Right, let's see if this works.
Perfect. Come on.
Yes.
That sounds really good.
That sounds better than this car ever has.
Now, we need to get this clutch pipe on.
Get the back fitted up. And we should be ready for the first test drive. Right, so let's get the old clutch pipe out.
See how difficult that is.
Now, if you're wondering why I'm changing the clutch pipe, it's because I broke the other one when I took it off.
Really expensive mistake that.
Now, I need to lower the car to get access to the pipe by the seal.
So, there's our new clutch pipe.
Uh and I just need to put the union on and I can pop that quick release end [music] in.
So, I plug the quick release into the union first and do it this way. This way it's pulling it all together.
It was quite tight otherwise.
That's my cup of tea.
>> I've got a cup of tea.
>> Yeah. You got any milk?
>> Yeah.
>> So, that's the clutch pipe done. We do need to bleed it, but for now, let's go and have a cup of tea and then come back.
But, because I've got the bumper off, it's going to make it a lot easier to bleed the clutch.
The bleed screw is just at the top of the gearbox on the passenger side.
So, we take the wheel off and we can see it from there as well.
So, let's attach this bottle to the bleed nipple.
And this is where we'll pump out all the fluid.
And if you follow the hose here right to the top, that's where you plug in the bleed nipple.
So, let's move to the front now.
So, we've got our DOT 4 fluid.
What I'm going to do is fill this up.
Put this onto here.
So.
And this has to go to 19 PSI.
>> So, the way I did that was I actually fluid in there. So, I loosened the bleeding plug with the socket. Um that's why I was not so worried about sharing it. It's plastic, so you have to be really careful to not to round it off.
Then, I just got the um this ratchet spanner here so I could tighten it up afterwards.
So, yeah. I think we'll can test it now.
Uh see if the car changes gear. Uh we'll leave it in the air and try it.
Uh and we can see if the clutch works.
So, what I'm going to do now is put it into gear and just check that the new clutches are working and engaging. And we should see the wheels turn.
And while I'm here, I'll go through a number of different gears uh just to check that the selectors are all working okay. And fortunately, they are.
So, I think that's everything. Wow.
Okay. We're finally done.
Um now, let's get the bumper and everything back on and we can maybe give it a first test drive.
Uh it's quite scary. Let's go.
Putting the bumper back on is pretty straightforward. You got your crash bar there. You got some heat shields down the bottom here.
I would say if you have two people with this bit, it's a lot easier. So, putting the bumper cover on, it does require you going backwards and forwards. Obviously, being very careful not to damage any of the paint. I actually put some masking tape down to stop any damage from happening.
But, it would really have been a lot easier had I had some help.
Once it's in place, we button up all the screws and we're good to go.
Let's get the lights in next.
The light clusters are held in with three nuts on posts, and then you have the electrical connector to connect as well.
Well, the last thing to do is put the wheels on and I also bought some wheel spacers just because I think they look good.
On the rear I've gone for 10 mil and on the front for 7 mil.
So not a great deal, but I think it does improve the stance. So let's get the wheels on and take a look.
Right, so I think that's everything back on the car now. I know I'm ready to give it a just a quick run around the yard.
Check nothing falls off.
Check the gears kind of work.
So yeah, let's give it a blast and fingers crossed it's all good.
It's really nice to see this up and running and looking like a car again.
It's been weeks now.
Need to have a massive tidy up in this place.
Lost the end.
Well, the steering went really heavy and look at what we have here. It's dumped all the power steering fluid. So let's have a look underneath and see what's going on here. It's under the seal.
I think what's happened is this quick release connector has come out.
It isn't good.
Don't tell my power steering fluid.
So, I need to have a look at that.
So, that's pretty annoying. Um what's happened is then the there's a quick release on those pipes and it keeps popping off. Um there's a retaining cage inside there which clips into the quick release.
But apparently they're really only single use. I mean, I unbolted everything, so I'm not sure why that's come out at all.
Um and it seems that you can't get a hold of those little cages. You can buy the whole hose which is a ridiculous price, like hundreds of pounds.
So, not quite the test drive I wanted today. Um yeah, it's a bit of a setback, but nothing major.
Um and if I get one of these specialized hydraulic hose people to come out, replace that quick release, uh then I think it'll be a lot better. Um unfortunately, they can't come out today, so I'll crack on with a few other jobs like tidying up.
But yeah, the engine is perfect uh so far, so that's the good news.
Um I'm going to get the car back in now uh and we'll have to come back another day to do the power steering and have the first test drive.
Never mind.
So, amazingly, recently I reached 10,000 subs and I thought I'm going to treat myself to something.
So, you can probably guess what it is by what I'm doing now.
Let's get this off.
We'll come back with something else.
So, here we go. I bought a cheap number plate from the DVLA, but I don't think it's too bad, to be honest.
Nice white screw, but I'm joking.
Got some nice Porsche dealer plates, as well.
Porsche High Wycombe.
Thank you, Neil, there, who always helps me out.
Actually, one of the subjects of Porsche dealers, they have just started a new club, um, like the Porsche Classic Club, and it's called I've forgotten the name. I'll put the link in I'll put it on the screen now.
But, it's similar thing where you get 15% off parts.
But, yeah, nice to join, especially for the cheaper parts. Believe it or not, Porsche parts are cheaper from them than you find on eBay and on other websites that sell Porsche parts. Always worth going to your dealer, especially with a 15% discount.
So, number plates installed, and isn't the car looking just great? I'm just so looking forward to driving this now. I can't wait.
Now, I've still got another day before the power steering can be fixed, um, so, I thought spend my time doing something useful.
I'm going to fit a dash cam. I thought it'd be really nice if I had a dash cam to kind of film the first drive, and yeah.
Let's take a look. So, I've been sent this one here by a company called Botslab. Um it's a Botslab G980H.
And this is a 360° um camera, so it's got a front and rear basically.
Um and it looks pretty neat.
So, let's have a look inside.
So, in inside the box then you get um this main camera unit here. Um it's got these two side cameras. So, this has interior-facing cameras, which is going to be really cool for my first drive video.
Um and yeah, that that goes in there. SD card it came with goes in there, so all good.
Now, underneath here we got some more stuff.
And there we got our rear camera.
So, I need to find cuz we've got box, so I need to find somewhere to put that. Um I might put it on the rear roll hoop actually and see how that goes.
Uh but yeah, that's going to be an interesting uh thing to try.
And you've got another box here, which I'm guessing will be for the cabling.
Got a trim removal tool here, which is cool.
Comes with that.
Yeah, and this is um if you want to power it by your cigarette lighter, you can use this. But they did send me this hardwire kit.
Um and this will allow me to wire into a fuse box. We got accessory, ground, and permanent live. So, three wires to wire in for the fuse box.
Right, so I'm going to get this in the car. Let's take a look and see where we can put it.
So, I think with the rear camera, the obvious place to put it is on the wind deflector there.
I'll put it down there in the middle, I think, so it's kind of out the way.
And for the front one, I'm going to put that underneath the rear view mirror there.
All right. So, I'm going to put that about there. That's going to be in the middle.
There's a line for the antenna going down the middle. If you just put that to the left of it, seems to be perfect. And that will help me get it straight.
All right. So, what I need to do is remove the sun visor, and there's a screw underneath this flap here.
And we've got two screws uh just there.
Then, I can pull this A-pillar out.
And go down there into the fuse box.
And we can find the accessory live and a permanent live ones to use. I've got some fuse taps, so I'll probably use those.
Installation of this camera is really easy. As I say, you remove the sun visor, then you can get behind the trim at the top of the windscreen, go down the A-pillar, and then finally poke the wires down into the fuse box area. And it's that easy.
For the rear camera, you just remove the seal trim, and you can run it up to the back.
So, there are the fuse taps that I put in.
That one's permanent live. That one is accessory. I had to reuse an existing fuse for that one. Uh there was no free slot cuz this car's quite fully loaded.
But you may find that yours has some free fuses in that row.
So, the camera's in, and the last thing we need to do now is get the power steering fixed. And good news, the man has arrived from the high-pressure hose place. And he's going to replace that section of pipe which popped out. Um I'm just going to put some standard connectors in there instead of the Porsche one.
A lot cheaper doing it this way, and makes it a lot easier for the future as well.
And I guess if these hoses are used on trucks, it's going to be more than enough for this, isn't it? Application.
>> Loads more.
>> And there we have our replacement section of pipe.
Right, so good news, the power steering has been fixed. Uh we put a new pipe in, we bled the system, and it's all looking good. So, I think we're about ready for the test drive. Um I'm a bit nervous. Hopefully, nothing falls off.
But yeah, let's get let's get it outside and see what happens.
Right, so taking it out now. I'm going to keep an eye on everything like the engine temperatures, obviously. Um There's no rattling or no knocking, which is good.
Uh so, yeah, so far, so good. I'm going to do a quick drive around just just to check nothing is falling off. Um I'll come back to you shortly.
So, I'm having a quick drive around the country roads. Um taking it very easy.
I've obviously got the engine covers off, and I've got a fire extinguisher to hand just in case there are any problems.
And this footage is from the Box Lab dash cam. And if you do want one, here's the QR code again, and the link is in the description below.
But on the whole, there were no rattles, there were no knocks, there's no ticking, and I'm quite happy at this point.
Until So, there was a check engine light that's just appeared. Um a bit annoying, but [clears throat] it's not an important one because it's not flashing red, so I'm guessing it's some kind of sensor or something like that, and it's spotted something or something's come unplugged. So, let's go back and uh we'll hook up the diagnostic machine and see what it is.
>> So we got the diagnostic machine plugged in again. Let's see what this code is all about. And that's what it says on the dashboard at the moment.
So I need to look in the engine control module or DME section.
All right, we're in the DME. So let's read the fault codes.
See what this could be.
Uh catalyst efficiency.
Now, I wonder if that's to do with the old engine dumping oil into the cats.
Let's clear it. Um I'm going to think about that.
Okay.
Okay, clear. Let's see if that goes.
Yes, it's cleared it.
That's good. So it's gone.
So we need to keep an eye on that. Um yeah, see if I can do something to fix that, but I imagine that's to do with the old engine dumping oil into the cats.
A bit annoying.
So I went to Halfords and I bought some of this stuff here called Cataclean, um which should hopefully uh clear my cat out. I don't know if this stuff works.
You let me know in the comments below if it does. Um but we'll give it a go. It's worth a try.
Uh so what we need to do is I'm at about a quarter of tank petrol.
We need to pour this in um and then give it a blast for at least 20 minutes. I'm going to do longer than that, so let's get this in and we'll see how it goes.
Done. Let's go and give the car a blast.
I'm going to do quite a few miles on it um and I'll see if the engine light comes back on or not.
All right, so I've done quite a few miles since putting the cats clean in. I think maybe 70. So the engine light hasn't come back on which is really good news.
Hopefully it was just needing clearing out.
Yeah, obviously the old engine was bore scored so it dumped a lot of oil in the cats. So touch wood, I think we're there. Now what I want to do is put the engine covers back on. I think the car is now ready to drive properly and start using my day as my daily again. I also need to put the under trays back on the bottom now that I'm happy there's no leaks. Really surprised that I've had no leaks.
Water and oil is fine. The levels are staying good. I did have to bleed the car but yeah, it was all all very easy.
So I think what I'm going to do is go to a car show tonight, get some miles on the car. There's a car show in Whitewater Meerfield near me. So we'll pop down there. I'll take a few videos of the car driving about and if there's any problems I'll let you know but touch wood there won't be.
Let's get to the car show.
>> [music] [music] [music] [music] [music] [music] >> Well, that was a great night and the car got there no problem at all. And the good news is it's a few days later I've done well over 500 mi and I've had no problem so far.
The engine light hasn't come back on since I put the cat clean in. And also there's no leaks. Um, the fluids are staying at the right level. So, it's unbelievable really.
Um, I really thought I would have more problems, but I guess I did take my time, cleaned everything, talked everything to the right settings. So, yeah, I guess it wasn't all luck that this is where it turned out okay.
So, I think that's about it for this engine swap series. Um, nothing else to do. The car's complete. I'm using it as my daily now.
So, we'll end it there. Um, I've learned so much doing this. It's so cool to be able to take out the engine, see where everything is, see how everything works.
And yeah, I like I say, I've learned so much. I hope you learned a bit too watching the videos.
If you did enjoy this series, then please do check out the sponsors. Uh, BoxLab with a dash cam, which is the footage on that is amazing. And I'll definitely be using that in other videos. And also Mu Car, who gave me a diagnostic machine, which was so, so useful for this whole process. You know, checking the sensors, finding things like the misfire. All of this was really, really useful. So, the link for these is in the description below.
Please check them out. The next video will be out soon. Um, I'm going to do some interior mods to this car. And also, I've got a new car coming to the channel. So, I hope you enjoy that. Keep an eye on this gram if you want to have a look at that. Anyway, I'll see you in the next video. Until then, have a good time.
>> [music] [music] [music]
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