Recently purchased a rebuilt AAV from a gentleman who seems to know what he's doing. Went to replace mine, which seemed to be passing air when the engine was hot,to the point that I couldn't get the idle down with the air screw. Decided to compare them, immersing the bulbs in two identical cans filled with tea kettle water. Both closed fully and then, when the hot water was removed, retracted at the same rate and to the same point. Both bulbs were marked -30º.

The only difference was that his rebuild had a triangular opening to pass air and mine has a slightly larger square opening. My engine has always raced when cold, so I put a partial block in the hose leading to the AAV to control that. But, since both units operate identically as far as opening and closing, I'm wondering if my original might be the wrong part (for djet Mercedes or VW).

Does anyone know the proper Bosch P/N for the AAV on my 1970 1800E? Mine is 0 280 140 022. The rebuild is marked 013, but since it's a rebuild and only the guts are critical, I can't really go by that.

Promised to check with my source for a rebuilt AAV to see if he wanted to be mentioned here. He was happy to be. Sells on eBay and claims to always have a rebuilt unit for sale there. $255 (plus tax) and a $60 refund when you send back your old one. Ray is his name and his eBay handle is shopsmith2020. Find a listing for his rebuilds by searching for "Refurbished Bosch Volvo 140, 1800 Auxiliary Air Valve."

Ray and I had a lot of back and forth communication and he was always prompt to reply, extremely knowledgeable and helpful, and incredibly patient and courteous. When I finally figured out that my old unit was actually functioning properly, he offered to take his rebuild back. The minute he received it I got a full refund.

While I never actually mounted his rebuild on the car, I did hot water test it and it worked perfectly. Very nice workmanship. Indistinguishable from new. I would highly recommend this guy.

Thanks for follow up info!

As noted by others, the 013 with the Vee shaped notch is the correct AAV for a B20E. When you did your hot water test on the replacement AAV test to confirm that the notch was closing did you do a blow test into one of the ports of the AAV to confirm that the AAV is actually sealing? There should be minimal air leakage through the AAV when it is fully closed. According to the Volvo D jet trouble shooting manual when the engine is up to full operating temperature you should be able to completely block the rubber hose between the AAV and the manifold and there should be no change in RPM which implies no air flow through the valve when it is fully closed.

So, the first thing to check is to make sure that when the valve is fully closed it is actually blocking air flow. Make sure that your engine is coming up to correct operating temperature. If you have a low temperature thermostat the AAV may not be going fully closed at idle.

The D jet is a MAP based EFI so any air leaks in the system result in high idle speed. The obvious sources are the injector seals. The other less obvious source is the shaft for the throttle plate. I chased an uncontrollable high idle on my B20E for a couple of months finally narrowing it down to air entering around the throttle plate shaft. The throttle shaft is sealed with felt (the curious little felt washers that are included in some E and F top end gasket kits with no explanation as to where they go). The felt hardens over time becoming useless as a seal. Turns out that with a little work with a drill bit the pintle seal from one of the injectors is a perfect fit and provides a much more durable seal than the felt. Volvo does not list the little felt washer as a separate part so you need to find a top end gasket kit that has them included if you want to continue using the felt washer.

Check to make sure that your throttle plate / throttle stop screw and the throttle position switch are correctly set as per the service manual. In order to get idle set up correctly the throttle stop and the switch are set first and then hot idle speed is adjusted using the idle speed adjustment screw (which assumes that AAV is completely closed).

My B20E idles with a vey slight speed variation (not visible on a dash tach) around 875 RPM. A big bore engine by itself should not require a higher idle speed; however, a camshaft with more overlap will likely require a higher idle speed. Do you know what cam was installed in the engine? The stock D cam in the B20E comes with a fairly aggressive 282 deg (advertised) duration which results in a fairly high idle MAP. If your replacement cam has more duration you are going to have to crank up the hot idle speed, particularly if you combined it with a lightened flywheel.

As an observation, the D jet is a good system; but is not really good at accommodating significant engine modifications. Cranking up the base fuel pressure is a bit of a bodge to increase fuel delivery. D jet 'experts' can modify the system to deal with modified engines; but, that requires some soldering skills to go in and modify the hardwired filter circuits that establish the fuel delivery RPM & MAP profiles.

Wow. You should get "The Car Talk Golden Globe Award" for that reply. Who' da thunk to look at throttle valve shaft seals?

To bring this hopefully valuable thread to a close, I can provide the following updates:

The injector seals are relatively new. I recently checked the throttle valve carefully before adjusting the TV Switch. I double checked it today, when I also completely removed the air screw and chased it's threads (3/8"-16) as the outside end was a bit buggered up from years of adjustment. Following your advice, I made sure the AAV (my SAAB part) wasn't passing air when the engine was hot. It wasn't.

Now, with the air screw completely seated and the AAV completely sealed, my revs are about 1000 which, with the cam I have (no idea what cam it is) that's what it needs. However, I used to be able to adjust the air screw and get the RPMs much lower, so I suspect I should start hunting for a vacuum leak.

There's a bunch of auxiliary vacuum plumbing on this thing, which has been added to make the brakes work better and boost the idle when the headlights are on, but I crafted all that myself and am pretty sure it's solid. So I'll just start going through methodically, either disconnecting and plugging, or using the old carb cleaner spray trick.

Really want to thank everyone for their insights. It's nice to have some help when trying to sort something like this out.

The only way I was able to track down the manifold air leaks on my B20E was to hook up a shop vac in reverse to pressurize the intake manifold and then use a soap solution to check for leakage.

https://forums.swedespeed.com/showthread.php?201780-What!-Another-142-Project-Car&p=2330411&viewfull=1#post2330411

You need to cap the exhaust and rotate the crank to minimize valve overlap - which may be a problem on your engine if you have a gross amount of valve overlap. You also need to block off / disconnect the hose to the MAP sensor to avoid pressurizing / damaging it. If you have a mity vac hand pump perhaps test the MAP sensor to make sure that it does not have an internal vacuum leak.

What intake manifold pressure does your engine idle at? My B20E with a D cam idles at about 58 - 60 kPa (absolute) at 875 RPM.

The fact that you need an idle up function for your headlights suggests that the camshaft is very radical. I have an electric radiator fan on my car and the idle speed drops perhaps 20 RPM when the fan switches on and the engine has no problem operating at the reduced idle speed. Headlights are a non issue. Your low RPM torque must be incredibly anemic making for some interesting stop and go driving.

"BTW, there's also a switch tied to the throttle cable which cuts in the air temp sensor at zero throttle. This helped reduce the rich running stink that would always catch up to me at stop signs."

That is definitely a bodge causing the engine to run rich. I would be inclined to ditch that feature because I have no idea how far the D jet goes rich when you have a complete open circuit on the sensor. If you want to try and fine tune using that feature I would insert resistors in series with the sensor rather than completely disconnect the sensor or just raise the fuel pressure a bit more. You should probably be installing a wide band O2 sensor / controller with a display to monitor your AFRs so you have some clue as to what is going on. Right now you are pretty much like the (German ??) expression about a blind pig routing around for an acorn.

Boosting fuel pressure and disabling sensors seems like extraordinary measures to make the D jet work with your engine. Perhaps time to ditch the D jet and convert to a digital EFI.

Wow, blind pig rooting for acorns. Are you sure your not a BMW guy. Still,I can't really disagree with your assessment; yet the car runs superbly.

I've owned it for 20 years and the P/O did have an extreme job done on the motor. God knows what cam he put in it. It was blueprinted by a local auto machine shop while the rest of the car was refurbished by Swedish Motors in Marietta, PA. It had sat for a number of years before I drove it home and it was a rough six months getting to running acceptably (Until I found that the throttle plate screws had become partially undone, causing intermittent hell.) Then it was years "blindly" tinkering with other variables and combinations thereof, with the help of this forum (e.g. the advice on disconnecting the air temp sensor). It always ran rich, so I tried to combat that by reducing the fuel pressure, until planetman put me straight on that count. That solved the low-torque problem. It now shifts and pulls hard pretty much at the points a "normal" B20 should.

Having switched out a soft cam on a 142, one of the first things I tried to do was get the head off. Could not budge most of the head bolts, even with a 6' pipe on the end off a 1/2" breaker bar. Decided then and there to live with it best as I could until such day the the engine had to be pulled.

I have toyed with the idea of putting carbs on it, but that correspondence with John Parker abruptly ceased. Looked into MegaSquirt, but programming that is too nerdy for me. There were some guys up in Canada selling an alternative EFI system, but I can't seem to find them anymore. Anyone who can recommend a system a "blind plumber" could install, please let me know. I have the cash.

Considering my obviously demonstrated lack of skill as an auto mechanic, I'm still pretty proud of the work-arounds I've crafted. The car is now a joy to drive.

The company you may be thinking about may be StealthEMS; but, I think they are located in Nevada or thereabouts, not Canada.

http://stealthems.com/

The website still exists; but, I don't know whether they are still active so treat with care. Their system came with base fuel maps for a stock B20E / F which you no longer have so you would still have to go through the configuration / tuning process.

Stay away from John Parker. He has a reputation as a notorious rip off artist. High Performance Auto in Torrance is a reliable straight shooting parts vendor and shop.

"There's a bunch of auxiliary vacuum plumbing on this thing, which has been added to make the brakes work better and boost the idle when the headlights are on."

There shouldn't be any need for that. If the servo and the non return valve is leak free that should work fine with the standard single hose. If the battery is good and the alternator is charging as it should it should be able to keep up with the headlights for a long time at idle. How often do you need the headlights on for long periods when idling? The only idle boost mechanism needed is when you have AC.

Perhaps you didn't read the part about the aggressive cam. As least as far as the brakes are concerned, there is very little vacuum ever available to operate the brake servo. So I fitted a Pierburg vacuum pump (which I rebuilt) to work off the mechanical fuel pump cam lobe, and a Summit Racing accumulator tank to help give me decent pedal firmness. For safety's sake, this system is tied in with the original vacuum piping from the intake manifold. It required four vacuum check valves, numerous plastic tee's and connectors, a vacuum limiter, with air filter, and a million hose clamps.

As to the headlight idle, I thought I'd solved the problem, when turning on the lights by substituting a 55W alternator for the original 35W (anyone need an alternator?). But that didn't do it. Everytime I turned on the headlights the idle dropped an annoying 200 rpms and got lumpy. So I fitted an air solenoid, activated by the headlight circuit, which allows a bit of additional air into the manifold. Even included a little ball valve to allow adjustment of the flow and fitted the intake with a cool little red air filter. But, I know plumbing, but not so much electrics, so I you could suggest a more elegant solution I'd certainly be receptive.

BTW, there's also a switch tied to the throttle cable which cuts in the air temp sensor at zero throttle. This helped reduce the rich running stink that would always catch up to me at stop signs. Another MacGyver-ish work around that damn, hot cam, which I'd ditch in a minute if only I could budge the head bolts.

If only I lived in Torrance. I'm sure planteman could straighten all of this out. The engine has 40K plus on the rebuild and I've tinkered, ham-handedly for the most part, with all kinds of things, from timing, to the centrifugal advance, to the ignition to attempting to adjust another pressure sensor. All that it really needed, in the end, was the fuel pressure boosted. But, as mentioned, other than having the idle a bit high and a little bit of stink, the car runs and, now that I rebuilt the front suspension, handles like a dream.

OK. One thing I failed to mention is that my car was given a big-bore rebuild with a very agressive cam. This was done by the previous owner back in 1990. Car runs incredibly well (I've had many B-20 Volvos over the years, including a '72 1800) with fuel pressure boosted to 35 psi. Could it be that the experienced Volvo mechanics who oversaw that rebuilding had to go with an AAV with a larger orifice? Really would appreciate your comments on this point.

Item cost me $250 + tax on eBay, with a $60 core return fee. So, once I saw that my old unit was performing identically, I was reluctant to mount the new one in the event I wanted to return it. Gentleman who did the rebuild was extremely courteous and detailed in his communications. Claims to have successfully rebuilt more than 3 dozen of these, and the workmanship was very high. He also offered to accept the return if I was satisfied my original was working properly.

But I still have the issue of high idle, which I now think I might deal with, as I have partially, by decreasing the cross section of the connecting hose. Once we finish this discussion I'll seek the rebuilder's permission to put his contact info here.

Sorry, should have replied to the final message in this thread.

Dave;

"Could it be that the experienced Volvo mechanics who oversaw that rebuilding had to go with an AAV with a larger orifice?" ...only the rebuilders can answer that.

...but seeing as this component has been NLA for a while, one could easily see that they installed "what they could get"...the fact is a "racing" engine certainly has a "raised cold idle"...but if it was me, (a vacuum leak notwithstanding!, and I'd check for this first, but if idle comes down after AAV valve warms up, we wouldn't expect this to be due to a vac leak, ONLY AAV action) I'd orifice limit the AAV air flow to a more reasonable raised cold idle, with for instance some brass fittings between which easily replaceable washers could be located.

Cheers

At least this process has solved the mystery of why my car has always raced when cold. I'm always yelling at my wife to hurry up and get in because I don't want that cold engine sitting in the driveway running at 2000 rpm. Which brings me to my question.

Assuming normal, warmed-up operating revs of 900, on start-up, with a properly functioning AAV, what should the tach read?

As mentioned, I did cut down that initial racing by forcing s short length of fuel line into the inlet hose. That decreased the ID of and cut down the racing somewhat. I also disconnected and blocked the AAV lines and that made for horrible starting. So somewhere between the two extremes I think i can get this under control with the current unit, which, BTW, seem to have been from a SAAB. Makes sense since the Volvo specialists who oversaw the rebuild were also SAAB specialists.

Dave;

I would expect the manuals to specify a fast idle RPM, but since you are manually setting it, my seat-of-the-pants number would call 1400-1500 a good target.

Reference: https://www.sw-em.com/bosch_d-jetronic_injection.htm#volvo_fuel_injection_fault_tracing

Cheers

Dave;

According to my notes, the AAV marked ..022 is wrong and clearly from some other application... the ...013 number is what should be fitted to Volvo applications... for instance, I know a ...027 is what should be fitted (to some MB) application.

The as you have noticed, the shape of air bypass orifice one sees exposed when looking into the hose fitting when its cold (as well as also possibly temperature of sensing bulb, and angle of departure of the hose fitting from the casting) varies with the different vehicle applications.

In my research on the AAV, I have found the press-in depth of sensing bulb is critical and determines the operating characteristics of the valve. How does that rebuilt AAV function in your 1800? Do you still need to decrease bypass air when its open to prevent racing? Please give details of rebuilder...if he is doing a decent job rebuilding the AAVs, I'm sure others will be interested in his products as an option.

Cheers

Hi, my ‘71 E has the 013 installed. I believe that’s the correct number for ‘70 -‘73. Also for the 140 d-jet models. Sounds like the 022 is for something else. Bosch Classics had an online lookup for these, but that feature on their website disappeared over a year ago.

Found this says the 013 is correct.

https://fuelinjectionproducts.com/collections/auxiliary-air-valves-slides/products/volvo-new-auxiliary-air-slide-valve-bosch-0280140013-fit-140-1800-series?variant=7352138465333

It would appear that, given the larger orifice it’s for another, possibly larger engine.

Mine works and does it’s job properly. No over revving.

Hi, my ‘71 E has the 013 installed. I believe that’s the correct number for ‘70 -‘73. Also for the 140 d-jet models. Sounds like the 022 is for something else. Bosch Classics had an online lookup for these, but that feature on their website disappeared over a year ago.

Found this says the 013 is correct.

https://fuelinjectionproducts.com/collections/auxiliary-air-valves-slides/products/volvo-new-auxiliary-air-slide-valve-bosch-0280140013-fit-140-1800-series?variant=7352138465333

It would appear that, given the larger orifice it’s for another, possibly larger engine.

Mine works and does it’s job properly. No over revving.