fuel pressure woes
 

A couple of months ago, I noticed that my 97 TJ would talk a long time
to start unless turning the key to on a couple of times because I was
losing pressure in my fuel line. I replaced the fuel pressure
regulator, and everything was fine again. Everything was perfect until
a month and a half later, and now I am experiencing the same thing-I am
losing fuel pressure. I attach the meter to the fuel rail and it reads
49 PSI at idle (which is good), but then when I shut it off the needle
moves from 49 PSI to zero in a short period of time. Could this be that
the part I bought (from Mopar) was defective, or that I have a new
problem?

Thanks
Mike

Re: fuel pressure woes
 

97tjMike wrote:
> A couple of months ago, I noticed that my 97 TJ would talk a long time
> to start unless turning the key to on a couple of times because I was
> losing pressure in my fuel line. I replaced the fuel pressure
> regulator, and everything was fine again. Everything was perfect until
> a month and a half later, and now I am experiencing the same thing-I
> am losing fuel pressure. I attach the meter to the fuel rail and it
> reads 49 PSI at idle (which is good), but then when I shut it off the
> needle moves from 49 PSI to zero in a short period of time. Could
> this be that the part I bought (from Mopar) was defective, or that I
> have a new problem?

Could be, or it could be the check valve in the fuel pump. The probem
is hard to diagnose. Usually if you measure rail pressure with the
engine running, then disconnect the vac line to the regulator, the pressure
should go up 4-5psi if it doesn't or fuel runs out then the regulator
isn't working properly.

Re: fuel pressure woes
 

97tjMike wrote:
> A couple of months ago, I noticed that my 97 TJ would talk a long time
> to start unless turning the key to on a couple of times because I was
> losing pressure in my fuel line. I replaced the fuel pressure
> regulator, and everything was fine again. Everything was perfect until
> a month and a half later, and now I am experiencing the same thing-I
> am losing fuel pressure. I attach the meter to the fuel rail and it
> reads 49 PSI at idle (which is good), but then when I shut it off the
> needle moves from 49 PSI to zero in a short period of time. Could
> this be that the part I bought (from Mopar) was defective, or that I
> have a new problem?

Could be, or it could be the check valve in the fuel pump. The probem
is hard to diagnose. Usually if you measure rail pressure with the
engine running, then disconnect the vac line to the regulator, the pressure
should go up 4-5psi if it doesn't or fuel runs out then the regulator
isn't working properly.

Re: fuel pressure woes
 

97tjMike wrote:
> A couple of months ago, I noticed that my 97 TJ would talk a long time
> to start unless turning the key to on a couple of times because I was
> losing pressure in my fuel line. I replaced the fuel pressure
> regulator, and everything was fine again. Everything was perfect until
> a month and a half later, and now I am experiencing the same thing-I
> am losing fuel pressure. I attach the meter to the fuel rail and it
> reads 49 PSI at idle (which is good), but then when I shut it off the
> needle moves from 49 PSI to zero in a short period of time. Could
> this be that the part I bought (from Mopar) was defective, or that I
> have a new problem?

Could be, or it could be the check valve in the fuel pump. The probem
is hard to diagnose. Usually if you measure rail pressure with the
engine running, then disconnect the vac line to the regulator, the pressure
should go up 4-5psi if it doesn't or fuel runs out then the regulator
isn't working properly.

Re: fuel pressure woes
 

97tjMike wrote:
> A couple of months ago, I noticed that my 97 TJ would talk a long time
> to start unless turning the key to on a couple of times because I was
> losing pressure in my fuel line. I replaced the fuel pressure
> regulator, and everything was fine again. Everything was perfect until
> a month and a half later, and now I am experiencing the same thing-I
> am losing fuel pressure. I attach the meter to the fuel rail and it
> reads 49 PSI at idle (which is good), but then when I shut it off the
> needle moves from 49 PSI to zero in a short period of time. Could
> this be that the part I bought (from Mopar) was defective, or that I
> have a new problem?

Could be, or it could be the check valve in the fuel pump. The probem
is hard to diagnose. Usually if you measure rail pressure with the
engine running, then disconnect the vac line to the regulator, the pressure
should go up 4-5psi if it doesn't or fuel runs out then the regulator
isn't working properly.