New name and and new engine for Mina: an e30 for the GF

[Swanny]

Easier to do with it out for sure but can imagine it being done with the drive shaft removed....

[Andy.B]

What is involved with replacing transmission bushings, seals and wear items? Did it require disassembly? Something a novice could do? More importantly, what of this stuff can be done without having to remove the trans?

My trans is leaking (I think from the rear seal) so I wanted to do this and the shift linkage at the same time.

Keep up the good work

I replaced all of the shift linkage parts, transmission mounts, guibo, and the seals. Search on here for the dreaded 'bitch clip' to see what you're in for if you want to rebuild the shift linkage with the transmission installed.

It's all doable (except the input shaft gasket) with the transmission in the car, but since I had the transmission out, it was the perfect time to do everything at once.

With the engine and transmission work I've done on the car, I suspect the body will rust apart before I have to touch any of it again.

[Andy.B]

I'd like to some day sell my car and get another e30

Wait, you don't have an e30 anymore?

[Andy.B]

I got everything I could done on the car without the throw out bearing today.

I realized that the pedal bracket in the car didn't have provisions to mount a slave cylinder, but the one I got from a manual trans car didn't have the correct mount for the newer style brake switch. The solution? A quick cut and weld to match up the parts needed.


Auto trans out and in the scrap pile.


Clutch and flywheel installed, ready for the transmission.


I brought the 5spd near Betty, so it could get comfortable with its new home...


A little closer... I think they will get along just fine.


The throw out bearing should arrive sometime this week, so hopefully the car will be back on the ground and running by the weekend.

[Andy.B]

I worked on figuring out the wiring differences between the auto and manual transmission, while also sorting out how to make sure cruise control still works. It was actually easier than I thought, but pretty much every auto -> 5speed swap guide I read was incorrect (at least for my car), or made it harder than it needs to be .

First off, although I never have any intention of converting this car back to an automatic transmission, I avoided cutting or hacking anything in a way that would prevent restoring it to its original condition. For the wiring, that meant cutting the harness off of the shift selector side of the connector instead of the car harness side.

Then I modified the shift selector side of the harness to make it a plug in adapter. To do this, cut the harness about 4 inches or so past the range selector connector to create a pigtail harness.

The harness now has 5 wires:
Brown (ground for indicator light)
Green/Black (Park/Neutral signal)
2x Green/Yellow (Hot on run or start)
Blue/White (Reverse light)

To modify:
Connect 1x Green/Yellow to Green Black
Connect 1x Green/Yellow to either one of the two reverse light harness wires
Connect Blue/White to the other reverse light harness wire
Cap off the Brown wire.


I used heat shrink tubing to make it nice and tidy.
This modified harness provides the signal for the manual transmission reverse light switch, and the Park/Neutral signal to the ignition relay to allow the car to start.

For bonus points, cut a car harness side C301 from a parts car to wire into the modified selector range pigtail to connect to the manual transmission reverse light harness, making it a truly plug and play job.

That's it at the shifter, but there are two wires that need to be tracked down and disconnected. The Black/Green wire that provides 12v when in Park/Neutral goes to the DME and Cruise Control module as well.

One of the Green/Black wires goes to the DME harness to a Blue/Red wire, and provides the DME with 12v when in Park or Neutral. This 12v signal tells the DME to correct the idle speed for the engine load imposed by the torque converter when the transmission is in gear and the car is stopped. If you disconnect this on an automatic car when in gear, the idle bogs down. Since we don't have a torque converter putting a constant load on the engine, we don't need this function anymore.

Simply unplug the Green/Black wire from the Blue/Red wire coming out of the DME harness, and tape them up out of the way.


The next wire to disconnect is the 'cruise enable' signal wire (connector C143) from the cruise control harness. The ETK wiring manual states 'For manual transmission C143 is taped to cruise control harness'. C143 is located under the ABS computer on the driver side. The Cruise Control harness side is Blue/Brown and on the car harness side, you will find another Green/Black wire that come from the auto transmission gear selector harness). All you have to do here is disconnect wires and tape them up.
My phone died before I could get pictures of this connector.

What you are left with is a single Green/Black wire in the car harness telling the starter relay that the automatic transmission range switch is in Park/Neutral so it can engage the starter, even though the the range selector is now gone. The DME does not need this signal, since it isn't an automatic car anymore, and the Cruise Control won't work when getting this signal.

The effect of the modified wiring pigtail is picture below... it's really much simpler than it's made out to be:


* I haven't started the car yet to verify but I am certain that the DME wire should be disconnected, since it was disconnected when I got the car, and idled and ran fine EXCEPT when in drive but stopped at a red light, when the idle would bog down.

* I haven't verified the cruise control yet either, but considering the ETK tells you it should be taped out of the way on a manual car, that one is pretty obvious.

*According the the diagram, the Brown/Red wire coming out of the DME harness next to the Park/Neutral signal is unused. This is not true (at least on my car). It provides the speed signal to the instrument cluster through a Blue/Yellow wire that runs through the dashboard, and plugs into the green connector right next to the Cruise Control's speed signal wire at the cluster.

There you have it. Without cutting anything on the cars harness, you now have the car working as if it was equipped with a manual transmission from the factory. If anybody, for whatever crazy reason, decides they want to swap back at some point, then all they have to do is reconnect those other two Green/Black wires.

[n3rdy30]

Wow, you're motivated as hell man. Car is looking great.

I've got an issue with my reverse lights...PO hacked up the harness under the console, it shouldn't be too bad to sort, I've just been lazy about getting to it.

[Andy.B]

The car is now officially a manual. More to come...

[Swanny]

[Andy.B]

After weeks of delay due to waiting for parts, finishing up classes, and uncooperative weather, I finally got the transmission installed.



I ended up working in the rain all afternoon, making sure I was entirely underneath the car between the harder downpours, and working inside during the hail.

I got the interior back together minus a shift boot. I want to track down aged cardinal fabric to make into a pair of shift and e-brake boots to match the interior. For now a Momo knob with red stitching looks pottery nice in there.



It was too dark to get any pictures by the time I was wrapping up tonight. The only thing left is to bolt the exhaust back up, so I should have it all done tomorrow. The only real hurdle is that the threads on the exhaust manifold are pretty boogered, so I have to replace a few of them. I'm hoping heat convinces them to come out without breaking.

[Andy.B]

Alright r3v. It's sunny outside. It's not too cold. I don't have to work for 5 hours. I am committed to getting this car done today.

First autocross of the season is tomorrow. I could drive the Miata on H&R race springs and agx shocks, OR I could drive the e30 in stock class.

It's on.

[Andy.B]

aaaaaaaaaaaaaaaaaaaand, It's a manual transmission car now.

Just in time for the first auto-x of the year :)

[Andy.B]

I can't get over how much better the car drives with the 5 speed. I hadn't driven an I before, and it is a different beast. It sounds fantastic to rev it up between shifts, and man does it pull hard. Only thing left to do is swap the springs and shocks and get it aligned.

[Andy.B]

I have the car in pretty good shape now. I replaced the motor mounts yesterday, cleaned and lubed the passenger front window motor that was sticking, got a new shift boot installed, and gave it a wash/wax to clean it up a bit. The car is in great stock condition, ready to start modifying, except for one little issue.

The idle is a little funky. It starts up and idles fine when its cold or warm, but after about 20 seconds, the idle gets intermittently rough. It will idle fine for 5 seconds, and feel like it misses once or twice, then go back to idling fine again. The rpm doesn't really climb or fall when this happens, and there are no codes.

I have already replaced:
cap
rotor
plugs
wires
cylinder head
all associated intake gaskets/hoses
o2 sensor
temp sensor
idle control valve
fuel injectors
fpr
dme

I have checked and verified the fuel pressure and function of the fpr, cleaned the icv, cleaned the throttle body, and replaced every single possible source of an air leak. If I remove the oil cap, the vacuum leak makes a huge difference, so I am confident there are no leaks anywhere.

The car drives great and pulls hard, and honestly, I suspect most people wouldn't complain about the idle, but I know that it should be better, especially with a freshly rebuilt head, good compression, and having been fully tuned up. For all the work I put into this car, it should purr like a kitten.

I am going to replace the fuel filter because it's one of the only things I haven't replaced yet, clean and replace the ground points on the engine, and then swap in a different ignition coil and afm to see if either of those help. Lastly, I will try swapping out the crank position sensor to see if it may be faulty. If I still have the issue, the only thing I can assume is that there is damaged wire in the harness somewhere, which I won't look forward to finding...

Anybody else ever experience a slightly, intermittently rough idle?

[jd_e30]

I have the EXACT same idle situation as you. Intermittently rough. Actually, when I rev to 1k rpms it goes away, but just sitting at 500-700rpm it has that short, intermittent rough idle for a sec. Like you said most people might not care but I KNOW it should idle smoother.

My fuel filter was recently replaced, so I don't think that's your issue.


Maybe we are idling too low? In for solution!!! CPS sounds like a possibility and could also explain occasional / rare hard starts.....

[Andy.B]

I replaced the crank position sensor, ignition coil, and fuel filter today. No change. I checked every fitting and connection that could cause vacuum leak. No issues found.
I think you are right. It is trying to idle slightly too low. I am going to swap dme's later to see if that makes any difference, but I doubt it. Lastly, i'm going to adjust the valves again, but I doubt that will make a difference either.