firebird446

i have just completed the build of my lt1 and i have been driving it for around 350 miles so i can break it in and i was on the way home and it just started to buck and jump. then it died completly and no power to anything. so looked at the battery connection and tighten them and checked the ground wire over by the ing coil to body and it was loose so i tighted it up. now the car will not make it 2 miles down the road without missing out real bad under light throttle but if i wot it it clears out and starts to go but pops bad around 5500rpms. after it starts acting up it will barly idle. fuel pressure is 40-43psi and no ses light when it acts up but it will come on because i have the egr off and air pump off. im thinking the o2sensors are crappn out. cuz it runs like a top for two miles then falls on its face like open loop to closed loop just kicked in. any idea are welcome cuz since its a 1995 obd 1.5 crap i can't just find any scanner to look at live data......plz help

does it sound like fouled plugs? i have never fouled any plugs in a car so idk. I have the NGK FR3 plugs i have the edelbrock heads 61909. stock tune and injectors while im breaking it in before i thrash it on a dyno. i will be putting svo 30lbs red tops in for the dyno tuning

engine build: 10.5-11:1 comp,383 cubes ported edel heads and ported edel intake, degreed CC XFI280 cam, 54mm TB, 1.6 RR, LT Pacesetters and ORY, MSD cap on a stock optisparker, deleted the EGR and AIR

383ysi

Just a few ?'s...plug wires do they look burnt. I had a problem i could make it to town (15 miles) the it would start missing, plug wires were arcing bad when the temperature got up. Then the opti crapt on me causing it to backfire and buck and not run tight? Is the opti new or old...wires,did you put headers on at that time...they might be touching. Just some things to think about.

myltwon

iTrader: (1)

the running bad after driving for a few min could be failing electronics heatsoaking, like the icm or coil

firebird446

(to 383ysi) i have new wires that are routed in the stock location completly away from the new headers. new msd cap but the same optispark they either are good or bad and it seems to be sparking fine i used a ignition mate on all plug wires.

96capricemgr

iTrader: (1)

In addition to what has been said already.
Did you check the fuel pressure as it was acting up?? Reason I ask is one of the Impala guys had the CCP system act up and basically it would not let fresh air into the tank and after a little driving the pump would build vacuum in the tank and the car would "run out of gas" but once atmosheric pressure got back into the tank he could start it and drive again a little while anyway.

How about the opti vacuum lines, if the feed is plugged and vacuum builds in the opti the spark can jump farther under vacuum and could be carbon tracking.

firebird446

that is may next move to check icm and coil from my buddys lt1 that is known good..someone told me that the TPS is the problem like it was heat soaking so im also gonna try it also

firebird446

fuel pressure was a consant 40-43 when is acting up or not. i have also took the fuel cap off and drove it to see if it was in a vacuum but no change. as for the vent to opti lines they seem to be fine and not plugged but ill check them again