Hello just a quick update on the status of the CEL turning on after having my muffler replaced (from the Cat back).

I finally had time to check the codes. The system Reads 2-3-2 followed by a 1-1-3 code.

After seeing the 1-1-3 code I did the following based on recommendations posted here.

1. I listened to the injectors which all seemed fine.

2. I checked the resistance for each injector. They were all around 16 ohms.

3. I sprayed around the injectors to check for possible leaks..no problem yet again.

4. I removed the vacuum hose from the fuel pressure regulator and I did smell raw gas. From previous replies to my post I changed the fuel pressure regulator. As soon as it was changed the car's idle was much smoother.

Thinking that changing the pressure regulator fixed the problem we reset the codes and went driving. It was running fine but then the idle became rougher again and after about 2 hours....the Check engine light came back on and the codes are the same.

Now I am at a bit of a loss of what to try. Perhaps it is the O2 sensor that is faulty. I originally thought this because the CEL never came on before I had my muffler changed.

Does anyone have any advice or other items I can check.


Thanks in advance for all the help.

I believe that these were the codes that I got until I changed the O2 sensor. That was on a 1992 240 with 145 k. After changing the sensor, my problems went away. (Running rough, black soot out of exhaust on start up, and cel).

I had the same codes with a bad AMM. The standard test is to unplug the AMM (with the car off) and see if it runs better, but mine have always been just a little bit bad: occasional stalling or rough idle that got better when I replaced the AMM.

Hi Laine,

I thank you for the help and I will try this. Unfortunately I do not know what an AMM is. :)


Can you let me know.....is it a Mass flow meter??


Thanks,


Craig

AMM is Air Mass Meter... Volvo BS for Mass Air Flow sensor (MAF). To find it locate the large flex hose that runs from the throttle body on the driver side of the engine, follow the flex line to that chunk of equipment mounted to the inside of the strut tower, this is the AMM. While you are at it, check for cracks in that flex hose, a common problem at this age.

One last WARNING, only unplug or plug the AMM with the key out of the ignition... she ain't "plug and play", so do your wallet a favor, just in case it is still good!

jorrell
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92 245 250K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

AMM is Air Mass Meter... Volvo BS for Mass Air Flow sensor (MAF).

"AMM" is not Volvo "BS". It's Bosch's term for unit that measures Air Mass.

"Mass Air Flow" (MAF) is a U.S. oxymoron for a unit that measures Mass but not Flow, which are two different entities. K-jet measures Flow. LH measures Mass.

Growl grumble whatever, you'll go to two shops and get three different answers on this one.

The important thing with these units is to get the number off it when looking for a new (or good used) one. The automatic 92 240 should be LH 2.4, taking an AMM that ends with Bosch number "016".

If it's a stick shift, it may well be like mine: LH 3.1, with a rather more rare and expensive "001" AMM.

So be sure what you have before sourcing parts, especially when most places will not permit returns on this pricy item.

Good luck!
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::: Rob Bareiss, New London CT ::: 92 244 ::: 90 745GL ::: 90 745T ::: 84 242DL ::: 90 745T Parts ::: Used to have : 86 244DL, 87 244DL, 91 244, 88 244GL, 88 744GLE, 82 245T, 86 244DL, 87 244DL, 88 245DL, 89 244DL!