at a loss

[StangBoy]

So what i thought was spark blow out turned out to be a weak fuel pump so after swapping out the one from the 5.0 and it cleared up a bit and the fuel pressure doesnt drop off to 30psi under load now. but it still misses and sputters up top and if i let off it will die. fuel pressure looks good although it jumps up to 60 psi right off idle and tends to stay there. i have the regulator crushed a bit from when i was testing and plan to swap it out with a good one. i also tried the msd blaster ss coil off my 5.0 to see if that helped but nothing.

[Pshull727]

i was having a misfire bad at top end and now it runs good try to pull off the vac line from the bap and plug it.It helped my car car alot

[tripice351]

Your local Autozone should be able to run codes and/or a Key On Engine Running test for you for free.. just make sure the vehicle is up to operating temp.

And I don't think a BAP (barometric absolute pressure) sensor shouldn't have vaccuum going to it, that would be a MAP (manifold absolute pressure). A baro sensor just has an electrical connector and an open port, reading the baro of the current ambient air.

[Pshull727]

but he put a turbo motor in a mustang and if he just hooked it back up the way the stang was then there would be a vac line thats what i did and now i pluged the line and the car runs great

[StangBoy]

its not hooked up, everything is pretty much custom in this car as it was a carb'd 4cyl. ill pull codes tonite and see. at the autozone i worked at if it wasnt obd2 then we werent required to do anything unless we felt like it.

[StangBoy]

well i swapped out the regulator and not much change other than it isnt pig rich at idle like with the crushed one.

[futurexdesign]

Check the ETC , it tends to be the root of all evel in an EEC IV car. Look at the O2 sensor and TPS. If those are working it should have a decent mixture at idle.

[StangBoy]

Well today leaving the gas station i got on it a bit and it was fine. although i detected some ping. and i ran it through the gears again a few minutes later and it was fine but a way up the road it did it again, and its been fine off and one now but theres always a bit of detonation from what i can hear so i cant stay in it.

[gregpro50]

So it fixed itself?

Is the timing set properly?

[StangBoy]

So it fixed itself?

Is the timing set properly?

yes and no, its wierd. its also worse when its cold leading me to believe its the ECT sensor. the timing is set at about ~10. im gonna retard it tomorrow and see what happens.