1985 Cadillac Fleetwood Brougham Low Fuel Pressure

This was not a particularly difficult problem but I thought it was interesting. Engine would die out on acceleration and felt like it was running out of fuel. Customer said it happened all of a sudden. Checked fuel pressure at service port located at rear of throttle body. Fuel pressure was at 5 – 6 psi. Much too low 9-13 psi is the correct range with 12-13 psi desired. I disconnected the fuel lines at rear of car and hooked up my injector cleaning machine with internal fuel pump so that I could check the fuel pressure regulator for proper operation. 13 psi, great, diagnosis of faulty fuel pump.

I drained and removed the fuel tank and subsequently the pump and sending unit and this is where it got a little bit interesting. The fuel pump was not completely connected to the sending unit by the rubber hose and there were no clamps present.

It amazed me that the car had been driven 156,000 miles over 23 years and this hose had never come off before. I asked the owner if she had hit a pot hole some time just before the car started acting up and she confirmed that the road she now drives on has many pot holes and she has been hitting them quite a bit recently.

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