FORGOTENSTAR Posted April 23, 2008 Report Share Posted April 23, 2008 MAN.... I NEED HELP... I USUALLY FIGURE OUT ANYTHING ON THESE CARS BUT THIS TIME IM STUCK... IM RUNNING M.P.I. AND HAVE PROBLEMS WITH MY FUEL PUMP FAILING AFTER THE CAR HAS BEEN RUNNING FOR 30 MIN AT IDLE.. I REPLACED THE FUEL PUMP 3 TIMES (BOSCH 500HP) PULLED THE TANK TWICE TO SEE IF ANYTHING WAS PLUGGED UP, AND SIENCE IM RUNNING M.P.I MY MICROTECH RUNNS THE PUMP VIA RELAY,,, BUT ONCE THE CAR IS RUNNING ON THE HIGHWAY IT'S FINE,,UNTIL I HIT STOP N GO TRAFFIC THEN YOU CAN HEAR THE PUMP PULSATING TILL EVETUALY STOPS WORKING,, THEN AFTER AN HOUR THE CARS RUNS FINE AGAIN... PLEASE HELP IF YOU HAD THE SAME PROBLEM.. BY THE WAY THE CAR DID THE SAME TING WEN IT HAD THE STOCK INTAKE,, THAT'S WHY I WENT MULTIPORT... AND THE MULTIPORT I PUT ON IT WORKED PERFECTLY FINE IN MY OTHER CAR,,,,THANKS Link to comment Share on other sites More sharing options...
travs87tsi Posted April 23, 2008 Report Share Posted April 23, 2008 have you replaced the relay? Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 23, 2008 Author Report Share Posted April 23, 2008 have you replaced the relay? WELL IM RUNNING THE PUMP WITH AN AFTERMAKET RELAY AND IT'S WIRED STRAIGHT FROM THE RELAY INSTEAD OF THE STOCK WIRING ......AND THE MICROTECH ECU GIVES IT THE SIGNAL...........THANKS FOR THE REPLY.... Link to comment Share on other sites More sharing options...
travs87tsi Posted April 23, 2008 Report Share Posted April 23, 2008 how many amps is the relay you are using rated at? also is it a brand new relay? Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 23, 2008 Author Report Share Posted April 23, 2008 how many amps is the relay you are using rated at? also is it a brand new relay? 40AMPS AND YES IT'S BRAND NEW... NOW THE CAR DID THE SAME THING BEFORE IT WAS MULTIPORTED AND I THOUGH IT WAS MAYBE A ECU OR WIRE HARNESS PROBLEM SO THAT'S WHY I WENT MULTIPORT FROM MY BLUE CAR THAT AT THAT TIME THE CAR WAS RUNNING PERFECT WEN I REMOVED THE MPI,,, I CHANGED THE ECU,FUEL PUMP,AND MAGNA FROM MY BLUE CAR AND INSTALLED IT ON THE RED CAR AND THE PROBLEM CONTINUED,, NOW WEN THE PUMP STARTS PULSATING AND DROPPING PRESURE IF I HIT THE GAS IT WILL STAY ON AS LONG AS THE MOTOR IS REVING @ 3K OR HIGHER.. Link to comment Share on other sites More sharing options...
Zack_Morris Posted April 23, 2008 Report Share Posted April 23, 2008 maybe vapor lock? since it runs fine for extended periods @ higher rpms, but wants to shut off at idle. since it starts again once it cools off some, thats my opinion. Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 23, 2008 Author Report Share Posted April 23, 2008 maybe vapor lock? since it runs fine for extended periods @ higher rpms, but wants to shut off at idle. since it starts again once it cools off some, thats my opinion. HOW WOULD YOU FIX THAT PROBLEM??? Link to comment Share on other sites More sharing options...
Shelby Posted April 24, 2008 Report Share Posted April 24, 2008 first thing i'd sugest is useing more then one relay ,one for injs, one for ecu and one for fuel pump fuel pump can run the heat'd 02 for wb or nb 02's , also to be completely sure connect a volt meter to the pump power fed and monitor the voltage befor durring and after it shows the problem.. the reving the engine also causes the voltage to increase and the fuel demand to be more,,so i don't think it's pump relate'd , sounds more like a low voltage drop out you can just have a weak alt,, voltage and amps are two diff things , electronic devices will turn off at a min volts level due to the lower the volts the more amps is need'd to do the same work,,more amps equal more heat Link to comment Share on other sites More sharing options...
Chad Posted April 24, 2008 Report Share Posted April 24, 2008 A long time ago a member had this problem, it was their SMOG equiptment and fuel filler cap had failed, not allowign the fuel tank to breathe. Next time you get it warmed up and running, remove the fuel filler cap and see if you get a loud suction sound from it. A pump will sut down if it overheats, and it will overheat if it's having a hard time pulling fuel out of the tank because of an excess tank vacuum condition. Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 24, 2008 Author Report Share Posted April 24, 2008 first thing i'd sugest is useing more then one relay ,one for injs, one for ecu and one for fuel pump fuel pump can run the heat'd 02 for wb or nb 02's , also to be completely sure connect a volt meter to the pump power fed and monitor the voltage befor durring and after it shows the problem.. the reving the engine also causes the voltage to increase and the fuel demand to be more,,so i don't think it's pump relate'd , sounds more like a low voltage drop out you can just have a weak alt,, voltage and amps are two diff things , electronic devices will turn off at a min volts level due to the lower the volts the more amps is need'd to do the same work,,more amps equal more heat THANKS for the suggestions... but i do have seperate relay's for everything and you right it could be a voltage drop off. but im running a 120 amp alternator and it charges just fine.. but i will check the wiring system again Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 24, 2008 Author Report Share Posted April 24, 2008 A long time ago a member had this problem, it was their SMOG equiptment and fuel filler cap had failed, not allowign the fuel tank to breathe. Next time you get it warmed up and running, remove the fuel filler cap and see if you get a loud suction sound from it. A pump will sut down if it overheats, and it will overheat if it's having a hard time pulling fuel out of the tank because of an excess tank vacuum condition. thaks for the reply.. the way you descrive it it's about right... so it could be just as simple as a cap!! by the way i did pulled the tank down twice and replaced the little circulating reservour along with new hoses and it did not make a drifrence. but i'll change the cap and try running it without the cap thanks Link to comment Share on other sites More sharing options...
Chad Posted April 24, 2008 Report Share Posted April 24, 2008 In the case of the other member, their smog box was fouled with fuel (over filled the tank). Instead of vapors, it was flooded with liquid fuel so it gummed up the charcoal and turned to tar, making it impossible to breathe. I've also read artices on other cars (cadilacs) where this was a common problem. Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 24, 2008 Author Report Share Posted April 24, 2008 In the case of the other member, their smog box was fouled with fuel (over filled the tank). Instead of vapors, it was flooded with liquid fuel so it gummed up the charcoal and turned to tar, making it impossible to breathe. I've also read artices on other cars (cadilacs) where this was a common problem. Thanks for the reply... i get you but how did the problem was taken care off.... Link to comment Share on other sites More sharing options...
Shelby Posted April 25, 2008 Report Share Posted April 25, 2008 don't worry about a cure untill you find out thats the problem,, as to haveing the tank down twice why was that,, and what about the small in line cone filter in the fuel pump inlet , this is best serve'd being replace'd with an inline larger filter as shown on SOS by ProfQ Link to comment Share on other sites More sharing options...
FlattopMike Posted April 25, 2008 Report Share Posted April 25, 2008 You mentioned that the pump would pulse on and off. Could your return line be plugged causing excess pressure? Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 25, 2008 Author Report Share Posted April 25, 2008 don't worry about a cure untill you find out thats the problem,, as to haveing the tank down twice why was that,, and what about the small in line cone filter in the fuel pump inlet , this is best serve'd being replace'd with an inline larger filter as shown on SOS by ProfQIM BEGINING TO THINK THAT I MIGHT HAVE A BAD FUEL PRESSURE REGULATOR CAUSE I REPLACED THE FUEL LINE TODAY WITH A TEFFLON STEEL BRAIDED LINE AND GOT A/N FITTINGS TO AVOID LEAKS AND SAME OUTCOME.... ON MY MPI THE FUEL RAIL IS FED BY TWO LINES TO AVOID STARVING THE LAST TWO INJECTORS AND THE REGULATOR LINE IS EXECTLY IN THE MIDDLE TO AN CARTECH REGULATOR,, SO WHEN I REMOVED IT EARLIER AND TRIED TO START THE CAR, IT DIDNT START BUT THE PUMP STOPED MAKING THAT AWFUL SOUND,,,, SO I REPLACED HE LINE AND FITTINGS AND TOOK THE CAR OUT FOR A TEST DRIVE AND THE SAME THING KEEPS ON HAPPENING,,, WHEN IM IN GEAR ACCELERATING THE PUMP STOPS SQUEALING BUT IF SLOW DOWN TO IDLEE THEN THE PUMP ACTS UP AGAIN,,,,,,,WHAT FUEL PRESSURE REGULATOR YOU THINK I SHOULD USE?? I DONT HAVE THE STOCK REGULATOR FROM THE MAGNA,,, SO IM JUST RUNNING AN AFTERMARKET ONE,,, Link to comment Share on other sites More sharing options...
Shelby Posted April 25, 2008 Report Share Posted April 25, 2008 i'm useing the stock magma reg, and it looks to be the same as the one the DSM use or darn close i have a dsm fuel rail to look at but not able to do much out side right now Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 25, 2008 Author Report Share Posted April 25, 2008 You mentioned that the pump would pulse on and off. Could your return line be plugged causing excess pressure? THANKS FOR THE REPLY..... I CHECKED THE RETURN LINE LIKE 5 TIMES ALREADY AND IT FLOWS REAL GOOD,, AND EVEN BLEW INTO IT WITH 100PSI AND IT WAS OK,,,,SO IM JUST LIKE F^%*$$#^@@%@#TTT IM JUST GOING TO DRIVE MY SILVER STARION FOR NOW,,LOL!!! I DONT KNOW WHAT ELSE IT COULD BE REALY,, Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 25, 2008 Author Report Share Posted April 25, 2008 i'm useing the stock magma reg, and it looks to be the same as the one the DSM use or darn close i have a dsm fuel rail to look at but not able to do much out side right now I WAS THINKING OF USING THE A STOCK REGULATOR FROM THE MAGNA ASWELL BUT I WOULD HAVE TO FIND ONE WITH THE FUEL RAIL CAUSE MINE GETS FUEL FROM BOTH SIDES AND I TEE IN THE MIDDLE FOR THE AFTERMARKET REGULATOR,,,,,,,, Link to comment Share on other sites More sharing options...
Shelby Posted April 26, 2008 Report Share Posted April 26, 2008 not sure what that has to do with the reg, the ends have nothing to do with the reg location as long as it's a magna fuel rail it should still be same as oem,, i doubt if you gain any thing by flowing fuel in from both ends,, the supply line will flow enought fuel for 3 or more engines all runing at the same time . unless you have some sort of restriction in one end or the other Link to comment Share on other sites More sharing options...
FORGOTENSTAR Posted April 26, 2008 Author Report Share Posted April 26, 2008 not sure what that has to do with the reg, the ends have nothing to do with the reg location as long as it's a magna fuel rail it should still be same as oem,, i doubt if you gain any thing by flowing fuel in from both ends,, the supply line will flow enought fuel for 3 or more engines all runing at the same time . unless you have some sort of restriction in one end or the otherIM RUNNING 850CC INJECTORS SO WHEN I RAN THE MGNA RAIL STOCK IT LEANED OUT PISTONS 1 & 2 CAUSE THE 3&4 GOT MOST OF THE PRESSURE,, SO I MODIFIED THE THE FUEL RAIL TO BE FED FROM BOTH SIDES AND WELDED THE STOCK REGULATOR PORT SHUT,,, AND JUST TEE THE REGULATOR PORT RIGHT IN THE MIDDLE FOR INSURANCE ON KEEPING THE INJECTORS FROM LEANING OUT 1 & 2 PISTONS, THAT'S WHY... WHEN THE SET UP WAS IN MY BLUE CAR IT WAS RUNNING HELLA GOOD, IT GOT DYNNO TUNNED AND IT LAID DOWN 453HP @517 TORQUE... SO WHEN I PUT THE SET UP ON MY RED CAR IT WORKED GOOD FOR ABOUT A WEEK TILL ALL THIS FUEL PROBLEM ERUPTED AGAIN.....THE REASON WHY I SWITCHED SET UPS FROM BLUE TO RED IT'S CAUSE IM ENTERING THE GUMBALL RALLY IN TWO YEAR'S AND I NEEDED MORE RELIABLE POWER,,, SO IM GETTING A BIGGER TURBO (T76)AND BIGGER NEWER ECU... AND RIGHT NOW IM LOOKING FOR A REAR END TO @ LEAST GET MY TOP END IN THE 180MPH....SO ANYHOW MY FUEL PRESSURE REGULATOR IT'S THE ONLY THING THAT I HAVENT CHAGED AND AFTER A LITTLE RESEARCH I FOUND OUT THAT THEY DO GO BAD AND WHEN THEY DO IT DOES WHAT MY CAR IS DOING,,,,,,SO LL GET THE NEW REGULATOR NEXT WEEK AND WELL SEE IF I WAS RIGHT..... Link to comment Share on other sites More sharing options...
Shelby Posted April 26, 2008 Report Share Posted April 26, 2008 it's not gona lean out 2 cyls in the middle of the rail and have each end ok,esp the farthest one from the supply line,, i'd check the injs to see if you have them pair'd right sounds like you have the injs mispair'd and another thing with a fuel system pressure test under max boost and load any mis match of fuel flow will show up as a pressure loss due to low flow volume , have you check'd all fitings for a small hole causeing some resriction to flow volume , the smallest hole will control the max amount of flow thru the entire fuel line , and any posible air leak on # 2&3 cyls Link to comment Share on other sites More sharing options...
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