IanWatson

iTrader: (4)

Hey there just wanted to share a little tale of my SC400 hesitation issue I had , I got this car about 10 months ago and ever since i got it it had a harsh misfire that drove me BONKERS!! because I swapped to 5 speed that I couldn't enjoy ,for months I couldn't figure it out , at first I thought it was a electrical issue because the last owner had it on cut springs and the tire ate the harness on the drivers side .

After repairing the Harness I still had the same problem , and after hours of reading , or DAYS of reading and hunting , I tested everything from Coil packs at cold then after warm up to the maf sensor with a scope ,I even did the fuel pump ECU power bypass and replaced the Pump and it still didnt fix it . Then about 3 months ago I figured I wanted to beef up my fuel system for my few new mods I am installing , At this point i have replaced my Lines /filter/ pump/ Then it clicked I forgot to check my Fuel Pressure Regulator ..... I ran a gauge and the walbro was pushing upwards to 80 psi and the pump got cooking hot , I installed a Holly FPR and boom the car goes like a bat out of hell no hesitation not even a skip of a beat , SO CHECK THE FUEL PRESSURE REGULATOR

Sorry for the long post but I'm hoping some day someone that might have the exact same problem as me see's this and it might help them

oh now I'm running -10 feed -8 return with a Aeromotive A1000 fuel pump

sc4doubleO

Was your misfire constant or random? Did it affect cold start ups?

IanWatson

iTrader: (4)

It was all the time , and my fuel consumption was horrid , but there were odd times it would not do it , like only a hand full of times it was fine,

flip3d

What should the fuel pressure be at? I'm upgrading to an aeromotive unit with a gauge soon.

ihiryu

iTrader: (7)

IIRC it should be like 35 with vacuum

OBEY414

Ian Watson:

Where and what type of Holley FPR did you purchase? Interested in fixing the same issue i am having. Thanks.

mtnrat

iTrader: (1)

X2

Thanks

IanWatson

iTrader: (4)

Hey there sorry been out of town , im using a holly FPR and this one is for after market lines , so i would recm finding a OEM one , or upgrade like what i did with lines, FPR , and pump

OG Dada

iTrader: (10)

Something similar happened to my SC400 when I fixed the leaky valve cover gaskets. I didn't notice that one of the plugs for the fuel injector was pulled because the plastic part that supposed to lock with the mate's already broken. But it was only for a couple of days before I found it.