The engine should run without the AMM connected. THe Ecu detects a open connection and goes to a 'LIMP HOME' mode where the engine is controlled under a preset set of running parameters. The fault you describe in my mind has 2 possibilities.
1. The NTC sensor in the inlet manifold between cyls. 2 & 3.
Its primary job is tell the ECU the temp of the engine to govern the coarse amount of fuel to be injected. The AMM tells the ECU the air mass entering the manifold and the ECU then calculates the Air/Fuel ratio to a finer accuracy with feedback from the lambda sensor in the exhaust.
When I destroyed my AMM,(by mistake, I thought cleaning it would help...Oh boy! What an idiot!) I had to drive 250 miles to get the new one..... WITHOUT the AMM connected. The car drove alright, but the fuel consumption increased by 30%, and was definately down on power but it does run without the AMM connected.
2. The fuel pressure regulator on the fuel rail..
The heat over time slowly destroys the diaphram inside the regulator and the fuel slowly, at first, weeps through the diaphram into the vacuum chamber, then via the vacuum hose, into the manifold. Thus excess fuel is drawn into the engine.
Generally this has a tell tail sign of becoming difficult to start and increased fuel consumption over a period of time.
You may also notice the hose form the reg. to the manifold is soaked in fuel.
I have never had a NTC sensor fail but from the literature I have studied and fault from other cars I have observed, the NTC can give a similar symptom to what you describe.

posted by 202.59.31...

• HELP!! AMM Problems??!!??, Jeff M, Mon, 8 Jul 2002 18:53:52
  • Re: HELP!! AMM Problems??!!??, Jeff M, Tue, 9 Jul 2002 15:05:19
  • If all else fails ..., RS , Tue, 9 Jul 2002 10:44:21
  • one more thing to try..., JimBlake , Tue, 9 Jul 2002 09:33:29
    • Re: one more thing to try..., Jeff M, Tue, 9 Jul 2002 10:39:15
      • Re: one more thing to try..., JimBlake , Tue, 9 Jul 2002 11:31:56
  • Re: HELP!! AMM Problems??!!??, clive, Mon, 8 Jul 2002 20:41:38 <-- Viewing This Message
    • Re: HELP!! AMM Problems??!!??, Jeff M, Mon, 8 Jul 2002 21:16:30
      • Re: HELP!! AMM Problems??!!??, Clive, Tue, 9 Jul 2002 04:11:55
  • Re: HELP!! AMM Problems??!!??, clive, Mon, 8 Jul 2002 19:53:37
  • wet spark plugs?!, hoolagin, Mon, 8 Jul 2002 19:14:50
    • Re: wet spark plugs?!, Jeff M, Mon, 8 Jul 2002 19:37:21
      • hall sensor. AKA distributor timing sensor, hoolagin, Mon, 8 Jul 2002 20:15:42
        • Re: hall sensor. AKA distributor timing sensor, Jeff M, Mon, 8 Jul 2002 20:20:59
          • different sensor, JimBlake , Tue, 9 Jul 2002 09:42:04

No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.

• Prev by Date: Re: hall sensor. AKA distributor timing sensor, Jeff M, Mon, 8 Jul 2002 20:20:59
• Next by Date: Sounds like detonation to me.... check head gasket..nm, MichaelG, Mon, 8 Jul 2002 20:50:48
• Main C900 Bulletin Board

StateOfNine.com

SaabClub.com

Jak Stoll Performance

M Car Covers

Ad Available

The content on this site may not be republished without permission. Copyright © 1988-2024 - The Saab Network - saabnet.com.
For usage guidelines, see the Mission & Privacy Notice.
[Contact | Site Map | Saabnet.com on Facebook | Saabnet.com on Twitter | Shop Amazon via TSN | Site Donations]

Random Saabnet.com Member Gallery Photos (Click Image)