1985-1998 [Subscribe to Daily Digest] |
 | [Main 9000 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
AMM? Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Fri, 10 May 2002 11:58:00
In Reply to: Engine Boggs, Agood, Fri, 10 May 2002 08:32:51 Members do not see ads below this line. - Help Keep This Site Online - Signup |
It sounds like the Air Mass Meter. When pulling away from a light, when you press the gas pedal and it feels like the car is ignoring you? If you were to floor it at that point, does it take off? When I say floor it, I mean at least 75% full pedal travel - many folks never hit the gas that hard.
If the engine bogs coming off a light, bogs at low RPM, but runs OK above about 2500 rpm or if the throttle is floored, then that sounds like a bad AMM. It measures the airflow into the engine, and the engine control schedules fuel based on that airflow. Remember - the gas pedal doesn't control gas - it just controls air, and the engine control decides on how much gas to add. If it can't measure air, you get no gas.
Once RPMs build up, the engine control figures out that you must be hitting the pedal, even if it doesn't see a signal from the AMM. The same with flooring it - there is a mechanical switch on the throttle body that closes when you hit 75% throttle, and again the engine control figures somebody is lying to it, but it believes the switch.
Oxygen sensors dont' work when cold. So for the first few minutes of operation in a cold car, the engine control can only figure out how much gas to put in by the AMM signal. Once the car (and O2 sensor) warms up, it can use the Oxygen sensor signal to help with idle. So a bad AMM can lead to poor idle when cold.
The best bet is to swap it for a known good AMM. Remember, there are two different AMMs out there one for early cars (86-about '90), and later. They look the same, and the connectors are the same. They are NOT interchangeable. Go by the part number. You have the classic -005 AMM in your car.
You can get a quality rebuilt from the vendors on this BB. Sobstory sells them for about $140 after core charge.
Good luck!
posted by 140.157.4...
, Fri, 10 May 2002 15:37:31, Fri, 10 May 2002 11:58:00 <-- Viewing This Message
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.
 |
 |
 |
 |
 |
