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My fuel issues are getting to my last nerve, and I'm wondering what it would take to just throw the k-jet in the trash and swap over to carbs. I'd have to plug my injector holes, remove all the k-jet electronics, reroute my fuel line, and get a new throttle linkage, but would there be anything else? I feel like I'm over-simplifying this, but after I get an adapter and bolt them on, it'd be a matter of routing fuel to them and just tuning, right?

or you could just get all the motronic stuff from an e30

Well what all would be involved in that swap? I'm open to all alternatives, I just want an idea of the investment I'm going to need to make to dump the k-jet.

For Motronic, you basically you need the whole inlet side of the engine - for cheapness, you could use a late e30 320i system. Also the front timing cover, distributor, and you need to modify the cam to fit the motronic distributor or use an e30 325i cam.

The L-Jet is simpler as you just need the inlet side of the engine, and can run the stock e21 323i distributor, but the system has masses of vacuum lines and is unadjustable.

I converted my e21 to L-Jet a few years ago, and it worked really well, solved all the reliability issues I had with the K-Jet.

The Motronic is smoother running, and can be chipped... either system is simple to wire up, so it depends what you're planning for your car in the end.

**EDIT - just realised you have an M10 engine in the US - carb is probably your only option. You could run the e30 L-Jet system from a 318i, but did you get those in the US? The L-Jet is reliable.

I've got the whole 318i injection set-up. I'm sure it'll fit in a box and could be sent over. PM me if you're interested?

As interested as I am, I'm a poor broke and destitute college student, so this is all quite a ways out. I'm just going to have to bite the bullet and improve my setup's problems to get it stable for a prolonged period of time to save up for an injection swap. I'm actually planning on buying http://www.amazon.com/CTA-Tools-3420-Je ... B008FJXA3M this week to help sort out some of my current fueling issues. That and I need a second vehicle to be able to get around while the swap is in process, cause I doubt I can do everything over a weekend. So there's lots of money inbetween this all

Why don't you swap entire intake and fuel injection from E30 318i ?
K-Jet works fine if maintained properly. Once it turns to the bad side, it's gone...
L-Jet is more advanced than K-Jet and more simple.
And it shouldn't be expensive...

Agreed - the L-Jet is a reliable system. I spoke of the vacuum issues, but they are still better than the K-Jet in this regard!

Could never understand why mercedes stuck with the K-Jet through to the mid-90s!

A carb manifold + a 32/36 Webber would also run well. Had an e30 316 in the UK when I was there with that setup and it was great.

Update! Cause updates are good.
I did the swap. My engine bay is home to a weber 32/36. I can't think of a single thing that didn't improve. I even comprised a list for you all -
1) More power
2) Better fuel economy
3) Lighter (A noticeable difference)
4) Starts faster
5) A fuel system that is so much more simple as a whole, that I plumbed myself so I know what goes where

And above all, that roar from the intake when the second barrel opens. Dear lord, I love it. That sound could put me to sleep at night.
The choke isn't working yet, but I can still idle high manually, so I'm not worried. Worst case scenario, I just have to replace the electric choke unit. I also have to fiddle around with my throttle linkage, but it does indeed work.

Good news! What about the choke, that's going to be manual with a cable?

Well its an electric choke, I have 12 volts to it, but it doesn't affect the idle one bit yet.

Yeah, I checked and it's definitely getting 12 volts too. But like I said, not the end of the world, and im still having a blast

Well but surely you want to know why it isn't working!

I'm mildly curious, I'm still in that shock phase of enjoyment with the car now, so that's been overriding the curiosity
I'll be sure to check it out this weekend though, as soon as the shock wears out I'll be tired of staying still for 5 minutes with my foot on the gas so the car can finally idle on its own.