QuestionQUESTION: I have a 1984 240 turbo.... My turbo recently went out...(oil bleeding into the intake, sever smoke) I had the turbo rebuilt, and no after reinstallation, the car starts fine and seems to run smooth for about 3 seconds, then it just shuts down.... like some one turned the key off. It does the same thing over and over, like maybe some system is telling the motor to turn off... what could this be?
ANSWER: Jose,
Either spark or fuel. Put a fuel pressure gauge on and see if you loose fuel when it begins to die. If not the fuel see if you loose power to the coil. You may have a bad coil, or ballast resistor, ignition switch, control unit, poor connection that is not allowing power to flow.
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QUESTION: To help eliminate the lambda system as a cause, will the engine start and run without the labda system. Where can i connect and check for fuel pressure(what pressures am i looking for?)
AnswerJose,
On the turbo you have to connect with a special adaptor/gauge to the fuel distributor. There you can read line pressure and control pressure and check rest pressure. Line pressure should be 4.7 to 5.2 bar and control pressure is cold 1.7 bar and as it warms up should rise to 3.7 bar. Rest pressure should not drop below 1.0 bar in 30 minutes. Bar is barometric pressure and equals about 14.7 psi per bar.
You can unplug the H02S and the frequency valve relay on the left side by the battery. Sometimes this will allow the engine to run without the influence of the Lamda. Now you may be better looking for a shop that works on Volvo's to help. That is if they have the special tools needed. You can possibly get line pressure readings at the fuel filter line, but nothing more.
