Volvo RWD 900 Forum

INDEX FOR 10/2025(CURRENT) INDEX FOR 11/2019 900 INDEX

[<<]  [>>]


THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD




  REPLY TO THIS MESSAGE    PRINT   SAVE 

1992 940 turbo - hard to start, poor idle and acceleration 900 1992

posted by  chrisbradberry on  Mon Mar 30 20:46 CST 2020
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Tue Dec 8 13:56 CST 2009
[RELATED]

Won't start and idle without first disconnecting AMM. If AMM is reconnected before engine warms some, the engine will stop. Idle is very slow, but engine doesn't appear to be misfiring. Can reconnect AMM after engine warms some, and eventually idle will improve some but still slow. When accelerating I have to accelerate slowly else the engine will bog down. Engine seems to be firing on all cylinders; runs generally smoothly. Seems like it's starved of fuel and/or air.

AMM, RSR, TPS, Power Stage, and ECU have all been swapped with spares. Ignition components are all relatively new. Fuel pressure at the fuel rail, with engine idling, is 45 psi. Checked all vacuum and air hoses for leaks and couldn't find any. Turbo spins freely, and turbo gauge behaves normal. When the engine bogs during accelerating the turbo guage doesn't change that much. If I peddle the accelerator slowly I can get the car to accelerate pretty well, but then it bogs down, and then when it returns to idle the idle is again slow.








  •   REPLY TO THIS MESSAGE    PRINT   SAVE 

    1992 940 turbo - hard to start, poor idle and acceleration 900 1992

    posted by  Amarin on  Tue Mar 31 04:05 CST 2020
    Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
    last visit: Thu Oct 23 22:42 CST 2014
    [RELATED]

    Check your air intake pathway from air filter box, intercooler piping, intercooler entry port for any foreign body, insects etc. Likewise check the exhaust system (after the turbo) for blockage eg blocked catalytic box.

    Amarin.








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      1992 940 turbo - hard to start, poor idle and acceleration 900 1992

      posted by  chrisbradberry on  Thu Apr 9 18:15 CST 2020
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Tue Dec 8 13:56 CST 2009
      [RELATED]

      Checked airway from air filter box thru to intake manifold, and it was clear. Also checked exhaust, and it was clear. Pulled O2 sensor and found it contaminated, probably from an earlier head gasket leak. Replaced O2 sensor, and car is running much better now. Thanks for the input.







<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.