JeremiahsC5

I thought I would share my fuel pressure issue with the forum to help out others. Car is a 2000 Corvette. I recently built a new engine setup for my car and in the process upgraded to custom fuel rails and an A&A fuel system that kicks on at 3lbs of boost. I did buy the kit used and there in lies one of the problems. I also have a Lingenfelter in tank fuel pump. When the car was finished and tuned I had no issues at all. After doing some work on the car in the garage I went to start it and it would not start. I started looking around checking for blown fuses and making sure I had power to everything. I ended up turning the key off and back on and it started. I ended up driving it a few more times with no issue. Then the same thing happened again at a car show. I was thinking it could be many different things. It ended up being fuel pressure. When I turned the key on I had a few seconds to turn the car on or the pressure would drop and the car would stumble and not start. I had great fuel pressure at all other times except for start up. After doing so research I realized that the A&A fuel systems were being sold with a speed flow check valve installed after the bosch pump. I was glad I found the problem and then just started making sure when I started the car I watched for the fuel pressure to peak and then hit the key at that exact moment before the pressure dropped. I got on the phone ordered the check valve and waited for it to arrive. Then the second issue started before I could get it installed. I would turn the key on and had no fuel pressure. Some times I could hit the key off and on and it would prime up and then start. Last weekend I went to drive it and tried it over and over and had no fuel pressure. I got on the phone ordered a new Lingenfelter in tank fuel pump. I installed everything today and have no bleed off at start up and the pump fired the first time. I can only guess that since the fuel line was bleeding back through the secondary pump that it burnt the in tank pump out. Hope this helps if you have the old A&A system with out the speedflow check valve.

BLOWNBLUEZ06

Sounds like you've been having a hard time.
I don't see the second pump burning out the first. It doesn't make it work any harder, it's just making the regulator do less work. I'm guessing it was just the pump's time to go. If it starts acting up again, check your factory connections. I've seen problems with the relay connections and the bulkhead connections with the pins getting loose and burning up over time.

JeremiahsC5

I hope it is resolved but I will keep that in mind. The way it was set up. The main factory supply line from the in tank pump was T off and ran back to the secondary pump and also the fuel rails. The fuel rails had a regulator on it before returning off at the bottom back through the fuel filter. The secondary pump with out the check valve installed was just letting the fuel go right back in to the tank. In my theory making the in tank pump work all the time to keep pressure to the injectors as well as the fuel racing back into the tank. The new A&A and bosh pumps come with a check valve. I bought my kit used from a buddy that had it on a 99 factory return fuel system. Not sure why he had no issues with no check valve installed.

BLOWNBLUEZ06

Yeah, the pump doesn't work any harder. Either the regulator has to dump the excess pressure or the secondary pump in your case before adding the check valve. The only thing that comes to mind that makes pumps work harder is higher voltage and restrictions and what else makes them burn out is low voltage and cavitation.

madmatt9471

Jeremiah,

Are you running any Racetronix Hotwire kits for you in tank pump? or just the factory wiring?

If factory wiring then I would suggest a Hotwire kit for it from Racetronix! these are great for keeping proper voltage to the factory set-up and are plug-n-play too!

Thanks,Matt

JeremiahsC5

No just running factory wires. When I ordered my new Lingenfelter fuel pump I saw that they had a wire kit that hooked up to the power on the alternator. Just might have to add that to the car.

madmatt9471

Yeah it's not a bad idea at all to run the Racetronix Hotwire kit that comes off the Alt:

http://www.racetronix.biz/itemdesc.a...WH-007&eq=&Tp=

Pretty cheap investment!

Thanks,Matt

robert miller

JeremiahsC5

Do I really need the wire kit even if I am running the secondary A&A fuel system. Drove the car all weekend after the check valve and new fuel pump install and no issues. The in tank pump must have been on its way out.

madmatt9471

No, however it is a lot better to have 10 gauge wire running your fuel pump as opposed to 16 gauge wire - especially the one that is your primary pump too!

Thanks,Matt

JeremiahsC5

I agree. Thanks for the info guys.

JeremiahsC5

Just to follow up. No more issues after new pump and check valve install.

madmatt9471

Awesome and thanks for the update!

Hey, Jeremiah - you ever here from Jason anymore?

Thanks,Matt

JeremiahsC5

After I bought his vette. We stayed in touch for awhile. He then bought a Camaro and was in contact with me allot more. After he sold it not so much. Its really been almost a year since I have heard from him at this point.

madmatt9471

Thank you for the update and if you should run into him, tell him I said hello and my cell number has not changed.

Thanks,Matt

JeremiahsC5

Will do.