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My Custom Engine Bay.

22K views 119 replies 15 participants last post by  GK27V6 
#1 · (Edited)
A lot of you probably have come across my Exterior Project, which I have effectively completed (well not entirely) and not yet unveiled to the internet- sorry guys; there's a good reason for it.

In Post #231 I wrote:

"After this exterior project, I do have plans for a shaved and partially-tucked engine bay anyway, so what I thought I'd do is lay the adhesive over the area, to act as a filler, and also smooth out other details. For example, I ground off some welded-in nuts which were intended to hold the washer reservoir and ABS module..."

Well I have been working on just that (and more haha).


Let's get started.

First, I am extremely grateful that I have been blessed with the opportunity to do this. I have a friend who's in the process of opening a car shop and has let me use the space to work on my car in my spare time. That said I have been working on the project on my own and expect it to stay that way. That is, I don't think my project will be receiving any additional or professional help from others.

Before this project, in October 2018 something went horribly wrong with my steering. Thankfully it was while I was in a parking lot. In short: it would steer to the left way too much, and to the right not enough (and even that wouldn't be consistent). I assumed the steering rack failed, which I expected to fail next on my car, and as such I had already bought a replacement steering rack ahead of time. So part of this project will involve investigating what happened and overgo its repair. I figure at this point I could as well do a full power steering delete, and it'd be best to replace the timing belt as well. over the 2018-19 winter I had the poor thing parked outside. Here we are at the end of March 2019 when I had it towed over:



Absolutely disgusting. The worst of it is not seen in the photo. This is what happens after several years of neglect + shortening CAI to prevent hydrolock (due to not having fender liners) + throwing and zip-tying things in the engine bay quick to drive the car again upon completion of previous exterior project lol (I can explain all of that). There is many years' worth of road salt, dirt, grease & oil all over the place.

Poor headers :( I will put in the effort to restore these.


Also, if you didn't catch it: one stud is missing - which was actually a bolt since I stripped the threads on the headers install so instead installed a longer bolt.

More on missing bolts later...

I don't like to start the thread off like this as a neglegence of care is not how I treat things; it's not who I am. So let's fix that.





More grossness here:


That is a coating of dirt stuck in place. Here it is cleaned up with some brake cleaner:


This side, while also dirty, is black because when I was 20 years old I thought it was a neat idea to paint whatever of the engine bay that I could until eventually I'd have it all black. lol, I was a kid...:


As for the steering rack. Well, it could have an internal issue (likely does), but it seems my issue was really mostly a simple matter of two out of four bolts having gone missing:


Also notice how disgusting this area is lol. More on that later when we get to the subframe work haha.
Now you might wonder: how do two bolts go missing? I have a guess as to why: solid motor mounts. I have them installed front & rear. Never in the ownership of my car had the steering rack been removed, or had its bolts loosened for any reason (heck, even the subframe has never been fully removed), so I cannot think of any other reason than extra and particular vibration frequencies causing them to loosen. The steering rack & motor mounts are all attached to the subframe after all. Anyway, between the steering rack having sported over a third of a million kilometers of use, having ripped boots, and having been in a collision it is worthwhile to simply replace the rack. Looking forward to doing that.


With the engine & steering investigation out of the way it's time to get onto the fun stuff 8)

Time to cut some profiles with cardboard:




Part of my project here involves closing up the engine bay (including the underside- more on that later) so that dirt can virtually no longer get into it ever again, ensuring it remains always clean. I have a few things in mind to help the aerodynamics as well :p That is, I am going to angle the radiator and vent the hood.
 
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#85 ·
Yeah, driving today, it seems that every time so as long as engine is in vacuum (correct me if that's the false term - basically just not giving gas) and simply pull the shifter out of gear below 1500RPM (without use of clutch) when approaching a stop then it won't do its fluctuating idle and simply stay at 1100. Still, 1100 is high for idle, but isn't all bad.
 
#86 ·
Yeah 1100 is still too high. Are you using the factory pcm? Actually, do you have access to a scanner to see air/fuel values? We really just need to see if you are super lean. That should tell you if you have a vac leak. I feel like your IAC probably isnt the issue here.
 
#87 ·
Running lean? Now you've got me concerned..
By PCM do you mean ECU? If so, yes, it's an early '03 2-bit. I do have a Hydra that I planned on making use of for going to stage 2, but perhaps I should try it out this week.


Also noticed that I think my car is consuming more gas, but a bit early to tell. Granted I have been stepping on the pedal a bit more since it sounds amazing lol, and am often in a low gear since that is how things are in Toronto with painfully slow speed limits and a speed bump every 5 seconds. Car feels truly excellent on the highway though; incredibly stable with the coilovers, Michelin PS4S's & manual steering. Anyway, getting back on topic lol... so as for fuel I did install a 190LPH fuel pump, and with the poor gas mileage I have been getting I was assuming running rich, though this I believe could very well be the ECU correcting a lean condition, so you might be onto something. Running the stock ECU as far as I could tell though should be fine I thought; I am running stage 0 Sniper (so stock injectors), but I do also have the 70mm TB installed, which initially I thought might've been a risk for stage 0. I was thinking to work out any quirks on stage 0 first before moving to stage 2. But come to think of it... I feel like my car isn't any faster at the moment than it was pre-SC (so I/H/E), so perhaps it is possible I am maxing out the stock injectors. Hmm... But one last point to consider is I have a smaller underdrive crank pulley installed. So my Sniper should be hardly generating any boost (but under pressing the gas pedal hard you can hear the whine). I was gonna use the stock crank pulley but the serpentine belt I have would be too small for it (due to my custom setup lol...).

Sorry for so many words, there's a lot of factors to consider at the moment :/

I do have access to a scanner, I'll see what it reads.
 
#88 ·
Somehow, your supercharger slipped my mind. And yes, PCM = ECU. Same thing.

So lets remember what a supercharger is... forced induction. By nature, you are stuffing more air into the cylinders. If you are on a stock ECU, you are absolutely going lean, and the computer is attempting to compensate. This absolutely will increase gas consumption.

But, we're focused on the idle atm. I know that some people had issues with cable length after installing the s/c manifolds. I would double check and make sure you have slight slack in the cable.

Also, check your reading on the throttle position sensor. Its possible the throttle body isnt adjusted correctly. Since its aftermarket, the throttle plate might have some adjustment like on the plate or even an idle screw.
 
#89 ·
Somehow, your supercharger slipped my mind. And yes, PCM = ECU. Same thing.

So lets remember what a supercharger is... forced induction. By nature, you are stuffing more air into the cylinders. If you are on a stock ECU, you are absolutely going lean, and the computer is attempting to compensate. This absolutely will increase gas consumption.
True. I am monitoring it, and it's seemingly not too out of whack. I have the OEM fuel consumption gauge (part of the multi-gauges) in my car and it's behaving fairly similar to what I remember driving my car last, i.e. from a few years ago so memory is not perfect on this lol.

As for SC though, I do have the smaller UD crank pulley. And my car performance-wise feels the same as it did pre-SC, so that smaller pulley is probably significantly reducing boost on the already low boost on stage 0.

Plus, if I was running lean I'd be getting a lean code wouldn't I? Currently only have codes for high idle and speed sensor. Granted, I have anti-foulers on the secondary O2's, so that may throw things off.

But, we're focused on the idle atm. I know that some people had issues with cable length after installing the s/c manifolds. I would double check and make sure you have slight slack in the cable.
True, but I did ensure it had a tiny bit of slack upon install. Still, I'll see what I can do there.

Also, check your reading on the throttle position sensor. Its possible the throttle body isnt adjusted correctly. Since its aftermarket, the throttle plate might have some adjustment like on the plate or even an idle screw.
Yeah good point. I mean at this point I actually have two stock TBs + 3 extra TB gaskets. I could very well pop on a stock one and see if that makes any difference.

For what it's worth I picked up an extra brake booster hose today from the wreckers. Came out of an I4 model but I get the feel it'd work. So I'll start with that.
 
#92 ·
Ok couple more things.

So does your brake pedal feel similar to when the vehicle is off? A stiff brake pedal is usually a symptom of a bad brake booster.... which just so happens to be vacuum assisted and also difficult to detect with the brake cleaner trick. When the diaphragm goes bad, it causes an internal vacuum leak. You can test this by pulling the booster hose off the manifold while the engine is surging, and stick your finger over the port to block vacuum. If the engine stops surging and idle comes down properly, you've found your problem.

Im not ruling it out, but I dont believe the issue is your IAC at the moment. If the motor starts to surge, its essentially trying to do its job. As the motor idles high, it closes the IAC to bring the idle down. It ends up being too much, and it opens again... causing the idle to go up. This is the surging condition. Basically the IAC is actively trying to control an out of control idle, usually due to a vacuum leak.

Get the vehicle warmed up. Use your scanner to check short and long term fuel trims.
Need to know both bank 1 and 2. What is the long term value, and eyeball an average short term value. Values should be similar on both banks as well. If one bank is drastically different, let me know that too.
 
#93 ·
Sorry, maybe I wasn't quite clear (was late in the night lol) but my brake pedal is not stiff. Now it's normal, lol. Previously, weirdly, it was too easy to press. The difference isn't that significant, but in any case it feels better. I do recall at one point (when I had the cracked vac hose on), while at idling at 1500RPM if I were to pump my brakes then the RPMs would raise to ~2000RPM temporarily. Just throwing that out there for anyone reading this to understand if they'd happen to have the same issue as I had.

Hmm, ok, I will let you know the values. I recall seeing the values and pretty sure they were normal but it's been many years since I have last dealt with fuel trims so my familiarity with them has slightly diminished since :/

Aside from that: I have been monitoring my fuel consumption it is noticeably better so far. My idle issue is also somewhat less frequent, but it's still there, and still always idling at a solid 1150RPM according to scanner lol. Haven't had a chance yet to replace LIM + gaskets, but I should have time for that hopefully tonight.
 
#96 ·
Trims tell what the ECU is doing with fuel amount.
Positive numbers means it's adding fuel (richining).
Negative numbers means it's reducing fuel (leaning).

Yes, best is "0" LTFT's....decent is within 5, acceptable is within 10.
Also, you really want the trims close.....not a 8 and a -8..... yes, 8 is OK, but they're 16 points apart...

STFT's can jump all over as you change load and throttle.
 
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#97 · (Edited)
Ahh, received a new CEL last night: P0449. Still have the original EVAP canister on my car, so might as well order some parts lol. Two years ago, when Ontario still did emissions tests, I almost didn't pass because the EVAP monitor wouldn't get ready even after a 1000km of driving or so. So this has been failing for some time (but granted I drove my car for only a few months of the last two years).

Edit: I recall my EVAP and fuel lines are also extremely rusty, so I am sure that's part of the issue. I planned on restoring the rear of my car this winter anyway, so I guess I'll deal with everything then. Only driving this car for another month this year anyway.
 
#99 ·
Well, after over 335000KM my EVAP canister finally failed. Had the best time filling up the car last night at an ultra slow pace lol. I have never over-filled my tank and I have owned by car since it had 193000KM on it. Must've failed just a couple days ago. I do wonder if it's related to a new issue I experienced then which was a hesitation, like misfiring, when going at a constant rate around 2-3K RPM. It felt like an ignition or MAF issue based on previous experience. But I do now wonder if it could be fuel related due to a failing EVAP system in some way.

Oh well, guess it's another trip to the auto wreckers for me lol
 
#100 ·
Theres a lot to unpack there mechanically. Technically everything you listed can cause those symptoms.

Im sure you are on top of it already, but for anybody else reading this... I cant stress this enough: start with what you know is 100% broken whether you think it might be related or not.
 
#101 ·
Theres a lot to unpack there mechanically. Technically everything you listed can cause those symptoms.

Im sure you are on top of it already, but for anybody else reading this... I cant stress this enough: start with what you know is 100% broken whether you think it might be related or not.
Yeah good call. Btw I plan on merging all these posts into another thread so that it's properly organized and so that others can make use of the information more easily.
 
#103 ·
Well update time for my mechanical issues: I believe I have found the source of my vac leak.

Story time!

This past weekend I went to a cottage with a group of friends. In planning the trip I was offered a ride to go, and that would've made perfectly fine sense to accept, but it was the end of September and I wanted to do at least one long trip with my car before winter would hit. Even being limited to 5000RPM and having a vac leak I figured it would still be enjoyable. And it was.



I really liked the way the car felt in the curves. The country roads are excellent with my setup of ARK coilovers, Progress sway bar, Michelin PS 4S tires, and manual steering. In that setting, and on the express highways it just felt so incredibly stable. On the way home, about half way of the 220KM drive it started acting up.

Since driving my car over the last few weeks I've had a hunting idle; indicative of a vac leak. This may have been partially due to a vac leak that I had in the brake booster hose (from being old and cracked) and although the car felt better after replacing that hose I still had the hunting idle (though less severe). A couple weeks ago there was that one day where there was a hesitation around 2 or 3K RPM when driving at a constant rate. I hadn't experienced that issue again but I suspected that was a failing ignition system so for the trip I did bring a spare set of coils, wires, and spark plugs, among a lot of tools as well. Well, good thing I brought the scan tool because I got a new CEL code then: P0121 - TPS issue. I pulled into a Burger King parking lot and went to see what I could do. Reading the forums it seemed this code was common for anyone running an SC either on stock ECU or poorly tuned ECU (I have the former; early '03 2-bit). So maybe the vacuum leak was related to this? More on that in a minute. Anyway, one member stated the issue would go away after an ECU reset, so I went ahead and did that. At best it worked for about 100 metres and then acted up again. Basically I would start to accelerate but it was jerky, and to call it a hesitation was an understatement; as if the gas pedal was an on/off switch, and upon being "off" it would abruptly slow down (as much as possible without activating brakes of course). Upon driving with this issue for a while I could start to figure out what was going on: With zero throttle engaged it would idle where it always would - so no signs of the engine shutting itself off (and indeed it never did). Then with some press of the pedal nothing would happen (most of the time) until a certain point. And the scan tool was showing just that: basically the throttle would register as 0 up until about 2 or 3 degrees (note this is on an NGM 70mm TB; values with stock might vary). So in other words: my options were to either accelerate or to slow down (via taking foot off the gas). So that's what I did. From that point it was express highway home (well, the shop) so I would fluctuate my speed to something above 100KM/H then back down to 100 again and repeat. Made for an interesting drive but was manageable.

Anyway, I started taking things apart. Basically with the way the engine bay is set up with the Sniper SC the TPS & IAC are at the bottom and difficult to get to with my custom work lol. So I took the TB off. I found it odd that the TB was actually quite dirty inside considering that A) I thoroughly cleaned it before install, B) I cleaned the IAC before install, C) the replacement engine I installed several weeks ago was very clean inside, D) I have a catch can installed, and E) I drove like only 1000KM since install.


After having taken off the TPS I noticed something:


To me that looked like oil had got its way in the pocket that the TPS module plugs into. That's really odd to me, because I believe there's only one way it could have gotten in there: through the shaft portion - it must not be fully sealed; i.e. a vac leak. To find out for sure I thought I'd install my stock TB, so that's what I did today: Behold, the hunting idle had gone away! And my idle was down as low as 850RPM (I know it should be lower still, but close enough; beats 1050-1100 it was otherwise at). Note however that I didn't reset the ECU though, I'll do that when I install my new TPS module which should arrive end of this week. I tested the throttle while I had the car in neutral and it still had the TPS issue. And on checking the scan tool the TPS registered as "0" the entire duration that I ran my car in the shop - I tested throttle up to 5K RPM. Now, I believe my issue here is the TPS module itself (as opposed to a bad tune like previously mentioned) and I believe this is so because I think the oil that seeped through might've gotten into the TPS itself and messed up the potentiometer within. I'll find out for sure when I take it apart this weekend.

Anyway, hooray, progress has been made lol.

Oh also on the cottage trip I hit a raccoon when it was dark and am currently fixing my bumper as well. More on that later - in short I am satisfied with how it got damaged lol.
 
#108 ·
Did you manage to fix your issue?
 
#110 ·
so, hows it been on this endeavor? on pause a lil?
 
#111 ·
Thanks for the continued interest. Yeah, I ended up having to take a break from it for a few months. And earlier this year I was mainly working on the CAD for what will be a full widebody kit. Looking forward to presenting that. As for the engine bay it's actually very recently that I got back into the groove of working on it. I'll have to post the rest of the progress from the last two years lol. Basically at the moment I am redoing some things such as the subframe, fuse box (relocated slightly, made a CF lid for it), and the carbon wall (firewall panel). I also got started on taking apart my engine but yep I've been slow with that as well. It's Canada Day today and I also took Friday off work with the intention of getting a lot done over the rest of the week. But I realize I should spend some time getting this thread up to date. Will take a good number of hours lol.
 
#112 ·
im eager to see what you come up with for the GK widebody. i had to start over on my idea for FL2 widebody since i had to move cross country. i still have the same intent, just gotta learn some lessons
 
#113 ·
Man am I terrible. But I really haven't had much time to post over the last year or two. So let's get back into it! Starting with where I left off, from approximately October 2019. At that stage it looked like this. And that was also when I picked up my FL2. Formerly a member's car by the screenname Jazzville.


This was also shortly after I got the engine in, which enabled me to get started on the wire tuck. But first, I'll go over a few sub-projects that I started earlier in this thread. I had to seal off the area around the radiator, so I made up some cardboard profiles.


Then I got creative with offcuts from the Optima hood. Cut up some pieces and joined them via fiberglass.



And boom here we go:




I actually got really lucky here. It turns out the space behind these panels fit the stock overflow perfectly. So that was unintended but worked out great, and so I ended up not going with an aftermarket reservoir like I showed way earlier in this thread, since no one will ever see it anyway:



Shortly after that things were looking like this:


And upon looking at this image at the time I realized there were a few things cluttering up the engine bay still, despite smoothing out all the surfaces. So in Photoshop I just quickly did this:


So that's it. At that moment I decided I must create a panel to cover up the busy area. That's a sub-project I ended up working on in 2020, which I'll cover in my next post. With this one I am simply wrapping up my progress from 2019. At the end of that year I ended up taking a break for a couple months anyway. It was a lot of work up until this point, but what's cool is that generally the engine and engine bay stage was coming to completion, and I could start transitioning into the exterior phase then.
 
#114 · (Edited)
Man, I'd write up 2020's post right now but I'm pretty tired. Spent the last couple hours familiarizing myself with this thread lol and writing the last post. Just to get a general sense of timeline though here's the short version of key events from the last two years to help explain my absence at least.
  • First half of 2020 was spent finishing up this project to the point where the car would be on the road, which included mainly exterior items
  • August 2020 it was complete, and immediately followed by a cam gear coming loose (despite being torqued to spec) for which I then bought a replacement engine and did all the work required to get it back to, or better than, the level of completion it was in August
  • I drove it for 6 weeks in September to October - had a lot of issues, though not really specific to my custom work - basically multiple vac leaks at the same time, fuel lines bursting, a failed TPS, failed evap canister, 5K limp mode, hitting a raccoon at night - all within a span of a few weeks, most issues simultaneously, so that was fun
  • During the 5th-6th week of driving it was in fact fun - then my replacement engine failed
  • Then for a good number of months I took a break, though I did occasionally work on other sub-projects for my FL2, or in some cases fixing it over a long period of time - it had a wide variety of issues as well but it's all good, I still have it and it's serving its purpose as my backup car
  • In the first few months of 2021 my mental health got into a place that was... not good, and had to change things up and focus on other things, at least for a few months - I got a new job then which was a major change of things, but that was exhaustive of energy for me at the time despite it being a non-stressful job compared to my startup days, so I spent a lot of my free time resting, not so much working on my projects (though they can be therapeutic often, just not so much at that time)
  • Since mid-2021 to present day I have gradually gotten more into the groove of spending my free time on these projects - overall I ended up redoing a lot of my work, but as well restored many other sections of the car that really need work, e.g. the rear end, 100% of suspension components, etc. - things that aren't the engine bay
I'll have you know I got my car back together yesterday, ready to fire. Except I am having an issue, which is not so bad because now I've had the opportunity to get experience and learn more about electrical systems with this car. Here's my thread for what I am currently trying to figure out: Fuel Pump not starting
 
#117 ·
i'd probably leave a provision to access the radiator cap and to let the rubber bump stops for the hood to protrude through that cover, but yeah, that concept looks great.
 
#118 ·
Yes indeed. Spoiler alert as it turned out the nose panel ended up practically sitting on the rad cap (I still ground away from material underneath to help that situation). It sits mainly on various points of the frame (upper rad support, headlight supports), as well as the two mounts for the bumper on either side of the upper grille. The hood ended up not needing the rubber bumps due to the Aerocatches, it's well-secured in position.

Thanks for keeping this thread active btw lol, I looking forward to writing up the next updates.

At the moment I'm deep into rehauling a lot of what's not seen in the interior (e.g. under carpet, replacing wires, etc.). One excellent discovery I made in that process is that using compressed air to clean up the carpet and trunk interior pieces is an excellent idea. Works better than any cleaner I've used so far. I even got a decade-old caked-in salt stains out. Then I ended up pressure washing the carpet too for good measure. My current plan is to fix up details like that over the next month, and drive the car in April. It is currently running, but, I gotta replace the O2 sensors, and before I'm doing that I'm installing a bunch of gauges including widebands (one per bank) so that I can monitor the before and after effects of replacing the sensors, and hence why I currently have the most of the interior out lol.
 
#119 ·
oh yeah compressed air is incredibly helpful.

i'm so glad you have continued on this.
i remember your 3d printed lip kit thread, that was somethin' i'm hoping to soon use that tech myself.
 
#120 ·
Yeah of course, not stopping anytime soon. Everything's coming together well to a good state of completion, I just have to redo the body this year. I ended up effectively redesigning it last year, and got started with printing it, then ran into some issues. I've come to know 3D printers as well as I do my cars lol, something always needs attention. My goal is to have the final version of my body kit installed this summer.

Yeah it'd be cool to see if you end up printing parts. Keep us posted.
 
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