hesitation

russ mater · Post by **russ mater** » 06 Nov 2004, 14:58

I have a '90 740 16V that idles well and runs well but hesitates and sputters when first accelerating. After the car gets power the problem does not reoccur until shut off and restarted. It is worse in cold weather. Warm engine still happens. Some mild popping sounds come from the manifold when it happens. New fuel pressure reg. and fuel pump.
Any thoughts appreciated.

Volvord · Post by **Volvord** » 06 Nov 2004, 19:34

You say that the fuel pump has been replaced but which one? Often on a Volvo hesitation is a sign that the low pressure in tank fuel pump is not working, this pump feeds a constant supply of fuel to the high pressure pump. I also assume that the fuel filters have been replaced.

Also check that the throttle position sensor is adjusted correctly, with the engine off you should hear a "click" when the throttle is noved slightly.