E30 323i Resource Thread

[agisthos]

Here is a thread that I hope will help those working on the E30 323i. This model is the most difficult E30 to find accurate information on. It was only ever available as a grey import into the US, but even in Europe it was only available for a short time before being superseded by the 325i. As a result there is no actual Haynes service manual available for it. There is a manual for the E21 323i and then the E30 325i, but not the E30 323i itself. The E21 is too different in too many aspects for the manual to be of use. The Bentley manual has almost nothing specific to this model.

There is also no ETM available online, anywhere. If you can get access to it please PM me so we can add it here.

The most difficult part of the E30 323i is the notorious vacuum timing system and it's complicated nest of small and large hoses going everywhere. This vacuum system is well known for leaking and never being quite right. There is also an air-slide valve that acts as an automatic choke for cold starting. Water runs in/out along with air to the idle control, when the water heats up the air valve slowly closes reducing idle back to normal.

When I recently had the M20B23 engine rebuilt, I approached 2 prominent BMW specialist garages in my home city and both admitted to me they literally have no idea how the 323i is put together, and that they could waste many 10's of hours labor time trying to get it working. So that's what promoted the research in this thread.

The E30 323i also uses L-Jetronic instead of the Motronic EFI system.

Thanks to the efforts on this forum of a Swedish user 'BMW Slangen' who 10 years ago stripped down a 323i for racing (and took a huge archive of pictures at every step) we were able to identify many peculiar things on this model, and also built a diagram map of the vacuum system that will surely come in handy for others.

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This is a diagram for the large vacuum hoses.
e30-323i-m20b23-hoses-large.jpg

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Diagram for small vacuum hoses, v1 (up to 8/84).
e30-323i-m20b23-hoses-small-1.jpg

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Diagram for small vacuum hoses, v2 (up to 8/85). The only difference with v1 is the removal of the ECU barometric pressure sensor hose, as the newer LE2-Jetronic ECU did not require it.
e30-323i-m20b23-hoses-small-2.jpg

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Diagram for small vacuum hoses, v3 (9/85 onwards). This was a production change removing two t-piece splits and is a simplification of the small hoses.
e30-323i-m20b23-hoses-small-3.jpg

[323i E30]

Awesome, thanks for sharing!

[superj]

Thats a bummer to have no tech data

[hotdish]

I have an '85 323i engine in my '79 323i and I just slapped 325i fuel injection on it since info and parts were so hard to find for the l-jetronic m20b23, not to mention mine was also modified with a piggyback emissions box that I could find even less info on. Good info. This would have been helpful.

[agisthos]

A variant of the E30 323i was produced with an early emissions systems. This was only available in the Swedish, Swiss and Australian regions, but may have ended up in the US.
There is no point to having this system in place, it can only be performance limiting. To remove it see the following....

These are the emissions pipes. It feeds cold air from the airbox back to 6 holes in the exhaust manifold for cleaner burning. A bracket attached to the thermostat screws holds it in place.
emissions-01.jpg


You want to remove this whole segment, plug the air intake box hole, then plug the exhaust manifold with M16 Grub screws with 1.5 thread pitch.
A thread pitch of 1.5 for this size is very difficult to find. Normally for M16 its 2.0, so you will have to use ebay and get them shipped from China. It will take weeks to arrive.
emissions-02.jpg

There is also an emissions valve that gives more vacuum advance when speed reaches 65km or 4/5th gear is tripped. This is for fuel economy or something.
Again, you want to remove it, as it can only interfere with engine timing, and by now this valve will have possible gone bad. See the earlier posted small hose diagrams, it's inline between the small hose from the distributor advance to the throttle manifold.

It sits on a bracket attached to the airbox, as shown below...
emissions-03.jpg

Here is an original workshop manual diagram of the emissions layout. It also applies to the E30 320i (according to this diagram).
emissions-layout.jpg

[agisthos]

A question in my mind, was perhaps the emissions cars are designed to have this stuff, and removing it can effect the running of the engine?

But a check of RealOEM showed the same ECU and distributor is used for the non-emissions 323i vehicles. The only difference is in the wiring loom (adding the extra power connector for the emissions valve). So its safe to remove it.

[Liamb]

Hey i juat baught an e 30 323i
And it wont start now..
It is getting lots of spark.. fuel is being pumped as far as the rail but not suer if its getting enough pressure.. it is really trying go start but just wont fire.. any idras??

[Thomas323is]

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Hey i juat baught an e 30 323i
And it wont start now..
It is getting lots of spark.. fuel is being pumped as far as the rail but not suer if its getting enough pressure.. it is really trying go start but just wont fire.. any idras??

I have the same problem. I keep crank the engine but it won’t start. Unless contact point of fuel pump relay close like I show photo. Some reason fuel pump not energized that why I roll a little
paper to keep holding contact point to make engine start!

Any idea? Thanks for all your help
Thomas, E30 Bauer 323i 1985!

[agisthos]

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I have the same problem. I keep crank the engine but it won’t start. Unless contact point of fuel pump relay close like I show photo. Some reason fuel pump not energized that why I roll a little
paper to keep holding contact point to make engine start!

Any idea? Thanks for all your help
Thomas, E30 Bauer 323i 1985!

Did you think the issue was the fuel pump relay itself? Or was this modification to the relay fixing another issue somewhere else?

My own car came with a spare fuel pump relay in the glove box (probably defective), do maybe that part dying is a common issue.

[Thomas323is]

Agisthos

I am not sure relay or not. I fell ground wire didn’t make good contact. That why engine only turn but no start after sit over night. But If I drive several time per day. I can start engine with no issue!

Thanks

[skismeno1]

Scratching my head on how to overcome an issue with the air-slide valve on my 323i.

Idle won’t drop when the car has warmed up so I’ve pulled off the slide valve. It only closes about 20% when I’ve put in a pot with boiling water. I’ve tried heating it with a blowtorch and the valve fully closes.

Is there a way to repair the valve? I can’t find anywhere and don’t believe a second hand one is going to fare much better than what I already have.

[agisthos]

Maybe try spraying lubricant inside it. Literally fill it up, and see if this unblocks/unjams whatever is in there.

Mine closed 90% of the way when in boiling water, and it looked pretty old.
But only closing 20% is not good. I would still look for a replacement at a wrecking yard if it stays that WAY.

[bigbadddbenny]

Our LE-Jetronic S1 323i is an Australian version 8/84 and I’ve refurbished it to run as stock, with the barometric sensor, emissions switch, and a working air slide valve.
Here’s the car on realoem via vin search:
https://www.realoem.com/bmw/enUS/select?vin=7538833

To delete the egr, I kept the pipes in place, for the stock look, but trimmed and crushed the probes inside the manifold runners, for less exhaust restriction, and blocked pipe to the airbox.

I managed to fix all the inlet tract leaks, using pressure testing at <1psi regulated air, soap bubbles and smoke.

I didn’t have a manual at the time so I found this site absolutely invaluable:
http://www.exx.se/techinfo/e30_info/

All the engine sensor test specs I found the forums.

Apparently the warmup air slide H valve can be refurbed using an ultrasonic bath, I’ve not tried this yet, as mine still works.
Alternatively, install a manual choke valve with a remote actuator, or use a later model electronic choke.

I had a crank no start issue, it was the fuel pump relay, which I blind tested using a fused 3-way jumper as described here:
https://www.r3vlimited.com/board/forum/e30-technical-forums/engine-drivetrain/m20/298079-m20b20-l-jetronic-no-start-fuel-pump-relay-problem-solution

The relay was stuffed so I replaced it with the oem revised part number, which I’ll dig up later.

I’ve since found a 1990 Haynes manual for 320, 323, 320i, 323i & 325i
isbn 1 85010 447 6

This covers K-jet, LE-jet and early Motronic. No LE2-jet alas. Interestingly this manual refers to K-jet as Series 1 and LE-jet as Series 2 and Late Model!

The vacuum diagrams especially for the distributor advance and retard are inconsistent due to model changes.
This is discussed in my Haynes and it states “up to March 1983 the black hose hose is for advance and the white hose is for retard. Do not mix them up.
After March 1983, the retard pipe incorporates an angled connector.” The latter connector is missing on my car.

The Haynes also has a photo for the distributor hoses, the white retard hose is shown at the rear of the vacuum unit, closest to the body of the distributor.
An adjacent diagram shows that as regards adjusting timing, minus is clockwise and vice versa.

Hmu if you need any advice.
Or search my posts on e30 enthusiasts australia fb group.

I refurbed and health checked all the systems till I was confident to present the car for an afm street tune using tailpipe wbo2.
They go really well once fettled!

[KenjiX]

I need help with my 84 323i my fuel pump went bad and I can’t seem to find one online. This is the only number that was on the pump 1154 628 217418-419-42

[agisthos]

The vacuum diagrams especially for the distributor advance and retard are inconsistent due to model changes.
This is discussed in my Haynes and it states “up to March 1983 the black hose hose is for advance and the white hose is for retard. Do not mix them up.
After March 1983, the retard pipe incorporates an angled connector.” The latter connector is missing on my car.

So your distributor only had 1 outlet for a small hose?

That is weird. I have an 07/84 and it has both outlets, front one angled. Maybe your dizzy was swapped to an earlier one with only 1 pipe? Apparently the E21 dizzy is better anyway, wound for a higher acceleration rate.

[bigbadddbenny]

I did mean I have both ports on the dizzy but the plastic L connector is long gone.

KenjiX, there’s two pumps on my 8/84 and I’ve replaced both.
They’re both generic fuel pumps with many equivalent part numbers.
Iirc I used a Goss intank lifter pump and a Bosch pressure pump in the guard.
I’ll dig up the info… edit this post…

So I find my car on realoem using the vin number… click browse parts and navigate to fuel delivery, fuel tank attaching parts…
https://www.realoem.com/bmw/enUS/showparts?id=1172-EUR-08-1984-E30-BMW-323i&diagId=16_0043

Click #10 and we see there’s three additional part numbers! Good clue it’s a generic pump used on other cars too.

https://www.realoem.com/bmw/enUS/part?id=1172-EUR-08-1984-E30-BMW-323i&mg=16&sg=05&diagId=16_0043&q=16141179415

At this point I’d plug the p/n into Ebay as the listings usually bring up the equivalent part numbers eg for other models or brands of cars.

Then buy the pump from a trusted local vendor online or local. Copies are out there lol.

Then repeat this process for the pressure pump… assuming you’re national version Switzerland, Australia Sweden of course!

https://www.realoem.com/bmw/enUS/showparts?id=1172-EUR-08-1984-E30-BMW-323i&diagId=16_0171

If you’re not the localised version, you may have a single pump. I’m not sure about those models but the parts translation process is the same regardless.

[agisthos]

I found trying to get an internal lifter pump for this model a complete nightmare, as there did not seem to be any aftermarket alternatives because they were all for the 325i.

I purchased one of those TR pumps to do the intank only fitment, but have not got around to it yet.

[MikkoRan]

Anyone knows, how close each other is the wiring (other than L-Jetronic) between 323 and 325? Since there is no particularly named wiring diagram for '84 323. So far I've only found diagrams for 318 and 325.