Volvo RWD 700 Forum

INDEX FOR 2/2026(CURRENT) INDEX FOR 3/2004 700 INDEX

[<<]  [>>]


THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD




  REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

Stumped on 744T poor running 700 87

posted by  someone claiming to be John Sargent on  Sat Nov 11 17:07 CST 2000 [RELATED]

Our son was driving his 87 744T when it started running very poorly. It runs like there is a bad leak in the intake system. It will run at 2500 rpm and above, but not well below that. The engine stalls easily. The engine also seems to backfire a little bit-the fitting at the brake booster was broken. I have checked the intake hoses and intercooler, replaced the AMM with a spare, replaced the fuel pressure regulator with a spare, and checked the timing. The fuel injection relay was previously re-soldered, and I just replaced the radio suppression relay with a spare. I have not yet tried the fuel injection CPU from my car, or tried the temperature sending unit for the fuel injection and ignition. Before I do this, what suggestions do I get from the brickboard? Yes, it is the original engine wiring harness, and it is rotten and needs upgading. We have three 740 turbos in the fleet, one 86 and two 87s. The problem occured instantly, although this car has had less torque at low rpm than either of the other two.







  •   REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

    Re: Stumped on 744T poor running 700 87

    posted by  someone claiming to be wbainlookalike on  Mon Nov 13 06:17 CST 2000 [RELATED]

    Well John, you had better get a re-wirin on the harness. First things first. Then check the distributor hall sensor for a signal. If those wires are damaged or the connector is broken it sure won't run very well.

    BTW, my can ran fine before harness replacement and it runs fine afterwards. Also check the short connecting hoses for the turbo lines. They could be broken. Also the turbo inlet hose at the turbo inlet. Mine was cooked and mushy. If the all tells the ECU there is a certain amount of air comming in and the air is leaking out under boost, the car won't run too well. Check the Idle Air Bypass hoses for splits. Check the intake manifold gasket for breaks, you can see this if the basket is broken and puched out above or below the manifold. Don't forget to make sure all the large turbo clamps are tight too.

    Good luck, w







  •   REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

    Re: Stumped on 744T poor running 700 87

    posted by  someone claiming to be Ian Billerwell on  Sat Nov 11 23:17 CST 2000 [RELATED]

    John,

    Craig Jordan ( neighbour and friend of mine ) has just had a similar problem with his 86 740T, cleaned the connector on the knock sensor and all performance returned. A good place to start.

    Good luck. Ian.

    PS: Craig also had a leak in the brake booster which wasn't helping.






<< < > >>



©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.