1993 Jeep Cherokee Fuel Pressure

TRUSOLDIER626

MEMBER
1993 JEEP CHEROKEE
6 CYL
4WD
AUTOMATIC
200,000 MILES

I have replaced fuel pump filter checked vac lines changed idle air valve throttle sensor. What I have got is when the igniton is turned on the pump puts about 30 psi into fuel rail but when u start the jeep the pressure goes down about 2 psi a second tell it final dies and there is no pressure in fuel system then u turn ignition on and pressure is back tell started. What can be cuasing this? There is also alot of sucking going on in the intake and backfireing. It is sucking in alot more air then it used to.

5 Replies

EUGENE123

MECHANIC
273 POSTS

Take your vehicle to a garage and tell them you want a fuel pressure test done this will help in finding the problem then post back to me with the results

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Thursday, March 26th, 2009 AT 4:17 PM

TRUSOLDIER626

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8 POSTS

Cant afford a garage thats why im here

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Thursday, March 26th, 2009 AT 4:30 PM

EUGENE123

MECHANIC
273 POSTS

You may have a faulty fuel pump that is working when the vehicle is on but when started not pumping the right amount of fuel to keep the pressure up

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Thursday, March 26th, 2009 AT 5:14 PM

TRUSOLDIER626

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8 POSTS

As in the first post I have replaced the fuel pump fuel regulator fuel filter vac lines and like 4 sensors as well as a few valves. It loses pressure like it is not building pressure and if it is it is not holding the pressure

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Thursday, March 26th, 2009 AT 5:43 PM

EUGENE123

MECHANIC
273 POSTS

You may have been sold a defective fuel pump the only way to know if this is true or not is to check the fuel pressure while the vehicle is running and if its low then you have a faulty fuel pump, sorry I have to be the one telling all the bad news :(