Fuel Pressure guage reading dropping
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
Likes: 0
From: Las Vegas Nevada
St. Jude Donor '07-'08
Fuel Pressure guage reading dropping
I have a 2004 and from a previous post i stated that my fuel pressure has been steadily dropping for about three months now. I am running Cobalt fuel pressure gauge, and a KB Boosta Pump. Normally i would run around 62 psi (cobalt gauge) and now it has dropped down to 50 psi. The fuel pump and filter are in the tanks. Just did a fuel pressure test and the pressure reads around 62psi. So i am relieved it's not the pump or filter. Any ideas of what it could be? OH, the vette runs great, no problems at all....
Last edited by PUREFUN; Oct 4, 2006 at 09:16 PM.
Safety Car
Joined: Jun 2004
Posts: 4,353
Likes: 22
From: Bella Vista Ca
Is the drop at idle or under boost?
My 04 would drop from 58 to 55 under full boost at 6000rpm. About 3 months ago it started dropping from 58 to 50 or lower under full boost ( this went along with the weather getting warmer). I ended up adding the ECS fuel system and now I am rock steady at 62.
I don't know if there is an easier fix..... I now I will never have a fuel pressure problem with the ECS system.
My 04 would drop from 58 to 55 under full boost at 6000rpm. About 3 months ago it started dropping from 58 to 50 or lower under full boost ( this went along with the weather getting warmer). I ended up adding the ECS fuel system and now I am rock steady at 62.
I don't know if there is an easier fix..... I now I will never have a fuel pressure problem with the ECS system.
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
Likes: 0
From: Las Vegas Nevada
St. Jude Donor '07-'08
Originally Posted by Mike04
Is the drop at idle or under boost?
My 04 would drop from 58 to 55 under full boost at 6000rpm. About 3 months ago it started dropping from 58 to 50 or lower under full boost ( this went along with the weather getting warmer). I ended up adding the ECS fuel system and now I am rock steady at 62.
I don't know if there is an easier fix..... I now I will never have a fuel pressure problem with the ECS system.
My 04 would drop from 58 to 55 under full boost at 6000rpm. About 3 months ago it started dropping from 58 to 50 or lower under full boost ( this went along with the weather getting warmer). I ended up adding the ECS fuel system and now I am rock steady at 62.
I don't know if there is an easier fix..... I now I will never have a fuel pressure problem with the ECS system.
It stays right at 50psi-51psi at idle. Drops a few psi under boost. At first i thought it maybe because of the heat also. Thought maybe i just needed to dial up my boosta pump. But the shop that did the install assured me it was set all the way up.
Safety Car
Joined: Jun 2004
Posts: 4,353
Likes: 22
From: Bella Vista Ca
If the tune on the car was set with the fuel pressure around 62 PSI and it is now closer to 50psi your car will be lean. The injectors are open for a given amount of time to keep your A/f ration in the safe range. The lower pressure will not push as much fuel though the injectors as before. This could be a very bad thing under boost....
Be very careful until you get the pressure problem worked out.
The Boost a pump only adds to the fuel volume under boost conditions. It would not affect idle fuel pressure.
You could have a bad sensor for you gauge, partially clogged fuel filter, bad fuel pump, the Boost A Pump could be messing up voltage to the pump causing it to receive less voltage..... I'm just shooting from the hip with these suggestions.
The first thing I would do is make sure that the pressure was indeed that low. I would get an external pressure gauge and attach it to the fuel rail to verify the pressure.
Mike
Be very careful until you get the pressure problem worked out.
The Boost a pump only adds to the fuel volume under boost conditions. It would not affect idle fuel pressure.
You could have a bad sensor for you gauge, partially clogged fuel filter, bad fuel pump, the Boost A Pump could be messing up voltage to the pump causing it to receive less voltage..... I'm just shooting from the hip with these suggestions.
The first thing I would do is make sure that the pressure was indeed that low. I would get an external pressure gauge and attach it to the fuel rail to verify the pressure.
Mike
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
Likes: 0
From: Las Vegas Nevada
St. Jude Donor '07-'08
Originally Posted by Mike04
The first thing I would do is make sure that the pressure was indeed that low. I would get an external pressure gauge and attach it to the fuel rail to verify the pressure.
Mike
Probably should have explained myself better. In my post i stated i did a fuel pressure test and it read 62 psi
Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
Originally Posted by PUREFUN
I have a 2004 and from a previous post i stated that my fuel pressure has been steadily dropping for about three months now. I am running Cobalt fuel pressure gauge, and a KB Boosta Pump. Normally i would run around 62 psi (cobalt gauge) and now it has dropped down to 50 psi. The fuel pump and filter are in the tanks. Just did a fuel pressure test and the pressure reads around 62psi. So i am relieved it's not the pump or filter. Any ideas of what it could be? OH, the vette runs great, no problems at all....
Instructor
Joined: Feb 2005
Posts: 228
Likes: 2
From: Phoenix AZ
St. Jude Donor '08
Had the same problem, twice. Sensors aren't cheap. One just stopped sending, the replacement started drifting like yours. Actually need to replace it now. If you find a good source let me know. About $150 at the vendor.
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
Likes: 0
From: Las Vegas Nevada
St. Jude Donor '07-'08
Originally Posted by B Taylor
Had the same problem, twice. Sensors aren't cheap. One just stopped sending, the replacement started drifting like yours. Actually need to replace it now. If you find a good source let me know. About $150 at the vendor.
Dell
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Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
Originally Posted by PUREFUN
Thank you guys so much for your replys. I have contacted the shop where i had my TTi and gauges installed. The fuel pressure gauge was only in about three months before it went out. Hopefully there maybe some type of warranty. Thanks again.
Dell
Dell
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
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From: Las Vegas Nevada
St. Jude Donor '07-'08
Originally Posted by trussme
Forgot to tell you that we did check my sending unit first...but it was OK...the meter itself was only reading 40psi...so it's possible that your sending unit may be OK, & only the meter is defective...mine was 4 months old & covered by warranty...
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 3,424
Likes: 0
From: Las Vegas Nevada
St. Jude Donor '07-'08
Originally Posted by PUREFUN
Contacted Extreme Motorsports today and they want me to send the gauge to them for warranty. If it's not the gauge they have the sender units in stock. Thanks again for the info.
