Volvo RWD 200 Forum

I have my check engine light on and I've been getting codes that say too lean/rich. I failed emissions the last time I went reading too lean (NOx). I've replaced vacuum hoses, cleaned throttle body, changed injector seals, changed air filter, cleaned and checked the bellows from the AMM up to the throttle body for leaks. I checked the throttle position switch.

After I cleaned the throttle body I checked the two vacuum inlets inlets just
before the throttle body (from the canister down by the left front wheel) and did not get much suction ... is that normal?

Also it will stall out when I first start it the morning and will stall agin when I first shift into gear. Also if I pump the brakes the idle will go erratic, stumbling ...


Any suggestions?




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Happy Motoring! 93' 244 and 2002 S60

Yesterday afternoon I met Art Benstein at his house. Art graciously offered a good 016 AMM to try out in my car. We swapped AMM's , my car ran well, his car coughed and died when my AMM was installed in it.

BINGO!

I hope to secure a used, verified good AMM online here ...
Thanks all for your assistance.
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Happy Motoring! 93' 244 and 2002 S60

The lean condition is most likely excess air from a lose or cracked hose.

The dieing after start up and things related to that are controlled by the limited range of the idle control motor. The hoses can get loose at the bellows hose or to the intake nipple. The valve itself may be dirty and slow to respond.


Jorrell mention the FPR. If it allows too much fuel back to the tank. The fuel pressure will be low and not system will adjust to load changes well. Its a good suspect! A deficit of fuel creates lean responses to load changes.

I'd think these over.

I thought about the brake booster which can fluctuate engine demand. It is probably good cause it holds vacuum. Just the other conditions are lean enough that its get in the game because of it size and requirement for vacuum volume.

After assuring the IAC and fuel pressure are working properly. I would go back though the procedure of setting the basic idle mixture to recenter the IAC system.

Good luck,
Phil

Have you checked the intake manifold gasket? You can use propane or acetylene gas to confirm a busted gasket.

With the engine idling fine, would I notice any difference if there was a leak when I passed the propane by the area? I tried yesterday but I think I need to undo the fan's belt ... all the air from the fan seems to blow any propane away.

Is there a home brew method for smoke tests?

I checked the AMM with an Ohmmeter and found it to be in spec. Also witnessed the burn off mode occuring (saw voltage after shutting engine off0. I took off the AMM and cleaned the two outer screens, they were sort of dirty.

I am going to recheck for leak at manifold and test fuel pressure this weekend ...
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Happy Motoring! 93' 244 and 2002 S60

Rhys'
Will check that ... thanks
Miguel
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Happy Motoring! 93' 244 and 2002 S60

Sounds like it may be time for a new fuel pressure regulator. Normally they fail rich but they have been known to fail the other way. The FPR is located on the front end of the fuel injector supply rail.

jorrell
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92 245 278K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

Sounds like your brake check valve or hose to and from the servo. I recently replaced one. If the check valve looks good it could also be the rubber seal around it. Both the check valve and seal where cracked on mine. It didn't solve my stall problem but it helped some. The servo can also go bad but not as common from what I've read.

My car didn't pass last time because my cap had a spring thing at top inside that broke and the plastic was melting around where it received that volt.

Ok, I checked and the Brake booster check valve is good (only blows in one direction). The rubber seal was good also. In fact, when I pulled the check valve out there was a rush of air as the vacuum was being held.

I'll look at the FPR but that sounds the opposite of my symptoms and the when I looked at plugs the other day they had a beautiful light tan to them, not the dark and moist that one would expect from a failed FPR.
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Happy Motoring! 93' 244 and 2002 S60

Hello Miguel,

You might try checking the connection at the AMM, or alternately swapping out the AMM with a spare.

Just plugging and unplugging the AMM to clear corrosion might set things straight.

Good luck and let us know what the prob was when you get it figgered.

Marty

Oleseahorse,
I do not have a spare, should I clean it with AMM cleaner?

And what is the significance of Ole Sea Horse?
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Happy Motoring! 93' 244 and 2002 S60

Hello Miguel,

There are almost always a few 016 AMM's on e-bay, so you might look there. I have a couple stashed away if you'd like to pay the postage round trip so you can try another one.

I've been led to believe that the connector is problematic especially in northern climes where corrosion can be an issue.

I'd remove the electrical connector and clean off the contacts. Alternately, you can remove and reconnect the connector several times to attempt a better connection. As for AMM cleaner, I might be out of place, but I believe it to be "snake oil" insofar as the AMM has a "cleanoff" very high temperature burnoff procedure at shutdown. You can read about it in the Bentley. Might be some discussion in the FAQ's as well.

As for the Oleseahorse business, I've been the Oleseahorse - sometimes just the horses ass too - since I had a CB radio in the 60's. It seemed to work OK then and seems to work OK now.

Marty Wolfson

Sounds like a bad AMM to me. Cleaning yours won't hurt, but in my experience, it probably won't help much. Try to get your hands on a good used one if you can (or borrow one from another car to test in yours).

Thanks,
I'll double check that. The last time I checked it only blew in one direction, I'll have a closer look at the seal also.
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Happy Motoring! 93' 244 and 2002 S60

Another scary way to test the AMM besides voltage checking by sliding back the rubber boot and probing. But if you remove the 10mm bolt and free the amm, then loosen front clamp and pull it up. Then start the car and gently blow into the AMM while running you should get the motor to either stall or rev up a little. You can also try putting a piece of cardboard partly over it but caution it may cause the engine to backfire which isn't such a good idea. After 1989 they don't have an adjustment on the AMM to compensate idle mixture.

The other important connector to remove and check for rust and corrosion is the ignition module which is located on the drivers fender beside the battery. I had to replace my ignition module as it gave first weak spark and then no spark due to age. Mine got very hot when it died. Also it was holding the coil at 5 volts on the white/red stripe wire side.