Hard starts then it bogs down

ALAN DEMCHENKO

MEMBER
1991 JAGUAR SOVEREIGN
172,000 MILES

I have a 1991 xj 6 has spark has fuel very hard to start dies when you press accelerator replaced plugs and rotor bug and fuel filter. I've replaced the plugs rotor button and fuel filter and wires have to feather gas to get it to start then it bogs at low rpm clears up a little at 3000 or more rpms dies under heavey acceleration

Monday, November 7th, 2011 AT 2:29 AM

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

This issue could be due to the engine not getting enough fuel. As you accelerate there is more air going into the engine which will require more fuel. If the fuel flow is now adequate it will bog down and can stall as well.

Low fuel pressure could be due to a weak fuel pump, it can also be due to a faulty fuel pressure regulator or a clog in the fuel lines.

Checking the fuel pressure is a good first step. This vehicle should have 42-45 PSI of fuel pressure at idle with vacuum disconnected.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

I have attached diagrams for your reference.

Let me know what you find.

Thank you.

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