So - about that wiring guide...
So we got a little busy. I originally wanted to get the wiring guide finished with the A/C working - that turned into a bit more of a debacle than I had anticipated and it still isn't done. Sneaking the hoses around the NA's framerail requires a bit more customizing than we had hoped for. And if you've ever had a project car before - you know that it isn't ever quite "DONE" done - there's long tail errors to fix.
And boy howdy did we have some.
Since we were using the E39a ECM, it doesn't have "good" alternator control. Our battery wiring is 2awg straight to the starter, then an 8awg crimped in the lug to the fuse box. The car will turn over just fine, but unless the battery is tip-top charged - it won't fire unless the ECM is getting enough juice. That led to a few issues - and us leaving it on the float charger whenever it wasn't driven. And the first breakdown on the side of the road - swapped in a battery from my other miata, no joy - took the old battery home and charged it - no joy. Eventually with a cheapy OBDII -> Bluetooth dongle and the Torque app, I noticed that we were only getting about 10 psi to the fuel rail.
Huh - that's not right.
So began the great fuel issue. When we got it back in the garage, pulled the fuel line off - and what came out was "powdery". We're using the Wix 33737 filter/regulator, but though, eh, maybe this was just a bad batch of gas.
A few days later - low on power - pulled out Torque - again, low pressure. This time it just was not behaving. I pulled the hard line from the back of the fuel rail this time - spilling gas all over hot headers on a 95 degree Georgia day. Fun times. That was enough to relieve whatever trash was in the rail and get home - where we proceeded to reroute our fuel line and incorporate an additiona 10micron filter from Summit. I also backflushed the fuel rail with a syringe and managed to pull some of the gunk out - it was white and very fine, like coffee creamer. Definitely getting past the wix filter.
With the new filter inline, everything was working much better. For about 2 weeks. Then that filter got clogged up. And the way I had designed it meant we needed crows foot wrenches to undo it from the hard line, and it still spilled fuel all over hot exhaust. Queue version 2.0 - this time far enough away from the headers to not ignite and you only need a 10mm and 2 adjustable wrenches to pull it off. Good thing too - because 2 weeks later.. yeap, again. At least the filter was catching it.
Except this time it wasn't the filter. It only died about 2 blocks from the house - so we towed it back in and - no whine from the pump. This was a brand new walbro 255lph hp from 949 and it was dead in less than a years time. Furthermore, the fuel sock was completely disintegrated. I reversed the polarity on the pump and it spat out something chunky and proceeded to run. We got some elbow-length gloves and proceeded to wipe all the gunk and crud we could from the inside the tank - it didn't look rusty, just specs of white crystals all over the tank. We tossed on a new fuel sock and called it good.
For another week. This time - new pump - it was kaput. No reverse polarity was fixing this. New sock. And once that was in, we took it down to the shop and dropped the subframe and tank and had it cleaned out. While the tank was out, we swapped the Wix 33737. I took the old filter and cut it open -
So.. Uhmm.. yeah. That's the fuel problem. Just wish that was all the problems...
The vibration problem
We had a problem with vibration - we weren't really sure if it was suspension or driveshaft or engine - or what. It started out subtle enough, but eventually it degraded enough so we could reproduce it - 2500 rpm was the worst vibration, starting about about 2000 and levelling off around 3000 - in any gear. So that mean.. ugh.. clutch. Really didn't want it to be clutch. We doublechecked everything else that wasn't clutch. I scoured CTS/Camaro forums looking for similar issues. Some people reported it and said they badgered the dealer until they fixed it, but didn't really say what the fix was.
It was the clutch. So we pulled the transmission out. Turns out - you really can't get the transmission far back enough from the bellhousing with the LFX. But being stubborn, we ended up loosening subframe bolts to get enough droop and with the right twist in the transmission - we got the transmission off.
This was waiting.
Out with the old and busted dual mass flywheel, in with the new Spec stage 1 single mass. We took a bathroom scale - stock flywheel, clutch, pressure plate = 48.6lbs. New stuff = 33.2lbs. And it looks nice. While we were there, we swapped out the concentric slave cylinder (more on this later).
So - we had to drop the front subframe out. While we were there - changed the wheel studs to ARP, I cleaned up some of the wire routing, new pads and rotors up front. With the clutch in - no more vibration!
But there was still a clunk. I didn't mention the clunk did I? Ah, well, there's a clunk. It seemed like it would "pop" when you went over seam in the pavement. Very hard to reproduce when you wanted to - and no amount of jiggling, prying, or pushing on suspension components while it was in the air would give us a similar sound. So - again - onto the CTS/Camaro forums and sure enough - the front differential bushing was blamed for a lot of NVH.
There are a few ways to swap the component - and even some tools you can rent to press the old one out and press a new one in. Or you can upgrade from the stock bonded-rubber-to-metal to higher-durometer polyurethane mount for $50. But I wasn't sure if this was going to work at all - so cheap was the order of the day. And I found a thread talking about the Energy Suspension 3.2125G bushing as being the right ID and OD, just a little long to fit. So for $20, we gave it a shot - cut a half inch off the poly and bushing by passing it through the bandsaw - and that clunk went away.
The ECM problem
Our dropout is from a 2013 with the E39a ecm and wiring harness from and automatic. And despite double and triple checking my wiring modifications, cutting a hole in the transmission tunnel so I could swap out the VSS sensor because there's not enough room to pull the sensor out - I just couldn't get a valid VSS signal. The E39a had some troubles controlling the alternator - supposedly - since it relies on the body control module to give it charge data - there is an override availible in HPTuners, but I was told it's a bit sketchy. So we didn't like running the E39a.
So - I went looking for another ECM on LKQ. Not that I'm particularly a big fan of LKQ - but you can at least see pictures of the car you're pulling the part from. But good god their web interface sucks - mostly client-side driven, so really hard to parse. I found a 2012 E39 ECM from a Camaro, and all was right with the world.
Except I didn't realize it then but I had made the mistake - again - of grabbing an ECM from an Automatic car. No problem - I'll just reflash it with a 2-day subscription to GM's tech service. Nope - das is verboten - stand-alone / bench flashing without the rest of the modules in the car is not allowed. Argh. The tune was working pretty well though, aside from VSS - except we started throwing bank rich codes in the LTR's. That meant that the ECM was pulling 25% of fuel and it was still running rich. My dad actually notices soot on the bumper before the code was thrown. I swapped the O2 sensors around, seeing if it was a sensor issue - nope. Then I read about "lazy" MAF sensors on the Camaro forums. Ah-HA! So we got a new sensor - and that didn't do anything. Dammit. But I realized something - the MAF cartridge measures air speed, but not volume. I realized that we had a 3.0in intake piping, but the "stock" camaro piping was 3 1/4. 1/4in doesn't sound like much - and I know someone with more knowledge of fluid dynamics will chime in - but 3.25^2 * pi = 33.2 vs 3.0^2 * pi = 28.3 - 33.2 / 28.3 = 1.17 = so there's a 17% difference in cross section. I pulled 20% authority from the MAF frequency table and the LFX really liked that.
Still unable to get VSS working I shipped it up to V8Roadsters and had them throw a tune on it to test if their stuff could get the VSS working - it came back, but something was.. funky. We own HPTuners - They use EFI Live. The car just didn't want to drive right. So I reverted my tune to something approximating "stock" and shipped it back to v8roadsters - and somewhere between - the ECM got fried (heck, it could have been shipping damage - I didn't static bag it..) Kaput. Back to the E39a, and back to LKQ. This time was much easier though - I found a VIN decoder card
So from that, I knew I needed a 1G1FE, 1G1FF, or 1G1FG vin - a lot easier than looking at LKQ's interior pictures to see if it was a stickshift or not. Found one, ordered, and it should be on my doorstep in 2 days since it's coming from about 50 miles away. A week passes, so I call. "Oh, it's shipping out today". 2 days pass with no movement on the tracking number. "Oh, it's coming today - sorry, catching up from the holiday weekend." I told them I would call tomorrow if I didn't see movement on the tracker - and I got a new tracking number. Yay!
Except when I got the package - the ECM was from a Chevy Captiva. I found another manual Camaro ECM (this time in California) and called them back to express my displeasure. All told it took almost 3 damn weeks, but I do finally have a manual Camaro ECM in the car. And VSS works! This is important for reasons I'll get into later. The ECM isn't perfect - performance wise, it's fine - but it's throwing p0300 codes (random misfire) at light load cruise about 2000rpm. Again, looking on Camaro forums - this might be a software update issue that (argh) I might not be able to get since standalone programming ist verboten. I'm playing around with different values between the Automatic and Manual before I disable to code completely - you can't feel the car misfire, so I don't believe it's a "real" code.
So - right now I'm just working on.. the slave cylinder problem. And this one is kicking my ***.
The new clutch and flywheel feels way better than the old one ever did. The pedal engagement is every bit as good as stock. And I hate lightweight flywheels - but this one is very manageable. For about an hour or two.
With confidence growing in the LFX's driveablity and with the new clutch, fuel system, ECM all in place - my dad took it up to the north GA mountains for the Polar Bear run on new years eve. I got a call a few hours later - and trying to bleed a slave cylinder on the side of the road while it's lightly snowing sucks - especially after you get a face full of brake fluid. We ended up uhauling it back to the shop. Once it was bled - hey, no problem right? Pedal felt great.
For about 2 hours. Again. Argh.
I'm having trouble bleeding the damn air out of the system. I mean - I've done it all at this point.
We've done your typical build pressure and open the bleeder valve bleed. Harbor Freights Mightyvac knockoff that I've used for years. Gravity bleeding. We've used a veterinarian's syringe with tubing over the end and reverse bled the system, pushing fluid from the slave up to the master like some gross enema. I took the brake-assist vacuum pump, hooked it up to a battery and pickle jar and built a power bleeder. Air keeps getting into the system. (And before anyone says it - yes, the master was bench bled).
The end of the clutch line is the nifty dry-break system with an O-ring. With the system deadheaded and stepping on the pedal, we've noticed no fluid leak. We've replaced the O-ring with the closest we could find in our harbor freight kits. Tonight I stuck the old slave cylinder on the line and gave the clutch a few pumps - I'm glad I put the whole assembly in a baggie because I managed to pump the entire reservoir out.
I *think* whats happening - I watched a video while trying to see if there's some trick to bleeding a concentric slave - https://www.youtube.com/watch?v=5YzTeyMUNjI
- and noticed they install a new spacer on the transmission face to edge the slave further forwards on their aftermarket clutch. Spec didn't mention anything like this in the kit we got - but I'm wondering if the slave being able to be pressed fully forward is leaking out / letting air in. I think the failures got more prevalent after I adjusted the clutch rod so the engagement point wasn't on the floor. If anyone has any ideas - I'd love to hear em. I'm going to find something to hold the slave back tomorrow like a pipe and c-clamp and pressurize the line to see if I can spot any leaks. I really hope we don't have to drop the subframe again.
Project cars, amirte? But it's getting closer to being daily-able, and it is pretty damn quick.
Oh - and I still need to get the A/C working.
On the upside - I have the wiring harness from my 94 Miata here on the floor, along with a harness from a 2011 LS3. So maybe I'll get around to documenting that - they're pretty close to the same. >