MSefi.com read only forum (Jan.15,2018)

I am interested in the use of a Bosch Auxiliary Air Regulator as mentioned in the Manual. Anyone experience with it and any idea in which cars they were used (SAAB 900 ??)

Arnold,

As far as I've seen, most L-Jet cars have them. The list of stuff with L-Jet is quite long - basically, look for 83-90ish Euro cars. BMWs are a good source, the occasional SAAB, and some Volvos. Most SAABs were K-Jet till they went Motronic - which doesn't need it.

Some of those cars ran K/KE till the bitter end - it really varies a LOT by model, motor, and market.

If you really have a hard time getting one, let me know. I can usually get one at the JY.

My (originally) L-Jet Porsche came with one, and so far, I have left it in. It works great, and it's a standalone - no new wiring, no new code, just powers up when you start the car. If it's cold, it's open. If the engine is warm, it's closed.

Greg

thanks, well L-tronic should be here to be found (Netherlands), I hope....

There are two different styles. One from a 1984 318i BMW, and another from a 1980 320i BMW. They both wotk the same, but mount differently.

The 320i BMW one is pictured on the Sensors and Wiring section in the MegaSquirt manual at almost the bottom of the page. Click here: http://www.megasquirt.info/manual/mwire.htm#idle

The other like mine for a 1984 318i BMW is just held in place by the hoses. Sorry I don't have a pic for it. Hope that helps!

arnold wrote:thanks, well L-tronic should be here to be found (Netherlands), I hope....

Ford 2.8i V6 engines have it (except for the very latest scorpios 2.8i which had EFI)
So look for Granada MKII or scorpio or earlier siera XR4i (later had 2.0 liter engine)

They are available in the Netherlands;-)...

Sietze

Any L-Jet or K-Jet cars should be able to donate theirs. Millions of these cars were made during the 70s and 80s, primarily German and Swedish, but plenty of Italian cars from the 80s used these systems, too.

I got mine from a Sierra XR4i (Cologne 2.8 V6 engine). Although I'm a bit confused as to how to hook this up to the MS ECU.... I've heard that you need to put a 6ohm resistor in there to make it work. The original one I have from my Mercedes V8 has no electronics (as it's a K-Jet system) so will work as a "stand alone" unit although I'm unsure which is best to use.
Part number for the one I have from the Ford V6 is: 0 280 140 132.

If it's the same as the one on the Mega Manual, all it needs is 12V fed to it; no interaction to the MS at all (apart from the fuel pump feed being the best place to feed it from electrically).

Don't forget that it also relies on engine heat, so neeeds to be bolted to somewhere at or close to engine temp (inlet manifold tends to work well).

Advantage of this unit is that it's a nice gentle reduction of the fast idle speed (no on/off), and also leaves the FIDLE wire spare for connecting to an EDIS in the future!

If yours is a XR4i (not a 4x4) then it should have Bosch K-Jetronic, hence will have the same valve as the Merc setup. AFAIK, there isn't a Bosch K-Jetronic-equipped (aka CIS) vehicle which doesn't use one. Even some of the L-Jetronic (not LE) setups used the same valve, so there shouldn't be any shortage of them!

Yup. The electrical connection is only there to run a heater. The basic device simply uses a bimetallic element to phyically open and close a shutter in the air bypass. The heating element was there to hurry the process along, esp. in cold weather. The engine bay temperature was supposed to provide most of the heat, but if it was cold out, the shutter may not close completely, or very quickly. The heater ensured that it did close fully by raising the temperature of the bimetallic element enough to do so.

Note, however, that in owning three different L-Jet cars and two K-Jet cars, all well-used by the time I got them, I've only seen one still working. The bimetallic element ages and simply stops moving after 15-20 years. It's easy to test: you should be able to see through the thing when the shutter is open, so place it in the fridge for an hour or so and see if it opens, then let it warm up to room temp and see if it closes. It probably won't close completely at room temperature, so you may need to heat it to 40-50dC. Hooking up 12v across the terminals should close it completely after a few minutes.

Last time I checked, they were still available new.

I found one, it has part # 0280140112, anyone?

arnold wrote:I found one, it has part # 0280140112, anyone?

All the Bosch aux air regulators that I've seen have been extremely similar, they were used in literally millions of car fitted with Bosch fuel injection in the 70's, 80's and even a few in the 90's, any one of them should do the job for you. Here's a diagram depicting the internal operation.

Also check the fuel injected early Datsun Z-cars for the air regulator. The 280z from 1976 to the 280zx in 1983 all had this regulator.

There is one in every front wheel drive Volkwagen from 1975-89 that has the 1.8L four cylinder engine. It is typically beneath the intake manifold on the upper rear of the engine and is mounted horizontally.

Look at any early EFi Rover V8 product - Rover SD1, Range Rover, Land Rover Discovery, TVR.