Red seven-nine

I just did a ls swap into my 79 malibu. Its a lq4 with a small camshaft And a few other small things. It has a aeromotive a1000 fuel pump Since im going to put the blower on during the winter. But When i get about 3/4 throttle it starts sputtering and acting like its running out of fuel. Somedays are worse than others sometimes it'll do it 10 times some just 2 or 3. Could this all be due to not having a actual tune on the car besides what speartech did when they re did the harness??? Any advice would be greatly appreciated

Old Geezer

iTrader: (3)

What's the fuel psi when this happens??

Reckless

iTrader: (9)

Running it external or internal? I ran the same pump external and it sucked for driving in heat. It would get too hot and lock up.

Red seven-nine

Not sure on the fuel psi. And it's external

Old Geezer

iTrader: (3)

start w/ the basics, instead of others having to play "20 questions"???

Red seven-nine

74 psi when ideling. havent got to drive it due to work and rain. Ive got it tuned still does it in both speed density and with the maf on. Checked to see if trash was in fuel filter so i ran a flow test and it flowed a gallon in 30 sec. ive checked the coil packs there good, checked the grounds there good, Ive changed plugs, spark plug wires are good. Any other ideas?? You can tell it wants to clear up but it just doesnt. Only does this when u ease on if from half to full throttle or you just hammer on it

Danny

iTrader: (16)

Are you sure you're not having problems getting fuel to the pump under hard acceleration? So you have a sump? Does it happen when the tank is filled as well?

Old Geezer

iTrader: (3)

74 psi at idle......About 16 psi too high.
And, the system is plumbed how?????????
Tank vented?
Scan/log and post them up.

[Part of the "20 question" process.]