lsEJ

ive had a problem the last few days where i will go to start my car and it will turn on everything seeming fine, then after a couple seconds the rpm needle lowers until it just dies, or will keep surging up and down. on a coldstart it takes a little longer to die, but nevertheless the motor just stalls. i originally thought it was a vacuum leak as i knew i already had one. i fixed the vacuum leak and the problem never went away. i was told to try fuel pump relay, so i got a new relay and that didnt work either. ive been doing so much research on this and most of the answers lead to something fuel related but me and my buddies held it at an rpm so it is getting fuel. could maybe be the ecu capacitators but that is smth i would like to look at last unless someone is certain that could be it. i feel like it could be some random sensor gone bad. tomorrow i will be grabbing wire and running diagnostics to try and get a code out of it. i tried listening for any more hissing from vacuum leaks but the hissing is gone. i am slowly losing my mind and dont know what to do, if anyone has any idea or can help at all or needs any more information. please please please help me.

BobAKL

Not familiar with the V8 but ...what rpm can you hold it at? Under load it will use heaps more fuel so could still be a dodgy pump. Can you disconnect the fuel line and measure the fuel flow or pressure? Can you borrow a known good ecu to swap for a test?

lsEJ

me and my buddies were holding it at 1-3k, we tested different times, didnt go above that cus car loud lol. ive been straying away from it being fuel because sometimes it will start up and keep the idle to the point where i can drive. for the most part it drives normal except at low speeds it will lag in acceleration and make the "blistering 7.2 seconds" turn into a solid 13-14 seconds. ill check out the fuel filter today, try to check out the fuel pressure as well. as far as ecu goes, the best i could do with the money i have would be to get a junkyard ecu, however thats a junkyard ecu with probably multitudes of issues.

BobAKL

I see that you can buy capacitors for your ecu on-line for a few bucks but I would check for fault codes before you do anything else. I assume you have seen this: http://www.lexls.com/tutorials/intro/codereading.html
or this video:

lsEJ

i actually bought a capacitor repair kit yesterday so it should be coming in soon. I watched multiple videos on replacing the capacitors and i over estimated it. doesnt look hard at all, just a very tedious job that will take time. after they get here and i finish the job ill come back to this post with an answer as to if it worked or not. thank you for your help!