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Volvo: 1995 Volvo 940 non turbo, 1995 volvo 940, bad cap


Question
QUESTION: Just installed a new fuel pump, had no pressure, also new filter. The care started bucking and chugging from 1k to 2k rpms. The car will then literally drop to around 400 rpm and will not rev over that. Shut it down for a few minutes and restart it will again drive but with the same bucking and chugging. Did a compression test and showed very good and even on all 4. Any ideas would be greatly appreciated, also might note it is a auto with only 106k original miles.
T

ANSWER: Todd,
Still sounds like something in the fuel system. Do you have the Bosch system with an in tank pump along with the under car main pump? Maybe the in tank pump is not working.

---------- FOLLOW-UP ----------

QUESTION: No, it only has the in tank high pressure pump. This thing puts out 200psi on all four cylinders cold with throttle open. The plugs were very wet when I pulled them to check compression. I also did an ohms test on all four injectors with them all disconnected, they all showed 16.3 ohms. Totally baffled!

Answer
Todd,
Are you sure that you are not overlooking something? I was meaning the fuel pressure at the rail when driving and also when the car acts up. If the pump in new, good but can the pressure regulator hold the pressure at 42 psi? Did you read the codes? What are they? Could there be some plugs misfiring? Bad cap, rotor, wires?