ignition cut-out vs fuel starvation
ignition cut-out vs fuel starvation
Sorry for another dumbass question, but could someone please describe the symptoms of each of these so I can better diagnose some problems?
yes NEW problems.... carb is still too rich, waiting on metering rods and jets, but I went DLIDFIS (thanks a MILLION jeff20b) and now my plugs are actually partially brown instead of black and sooty, partly black still, but either way a step in the right direction. I also found out that my secondaries werent opening for two reasons.... first, turned out the butterflies were actually hitting the intake manifold, some grinding stones and some porting on the primaries on the manifold took care of that. but they still werent opening while driving, they would if you cranked the throttle wide open by hand, turns out that my gas pedal wasnt moving the throttle quite far enough to get WOT unless you practically stand up on it when you are in the car, so if I try to push the pedal through the floor instead of to the floor, they open and my god they are loud! (thank god, hehe) anyway, even though they are now opening, it just makes noise with no difference in acceleration, its pulling higher rpm than before, and at high rpm, it starts cutting out, how would I best determine if its fuel starvation or the ignition cutting out?
yes NEW problems.... carb is still too rich, waiting on metering rods and jets, but I went DLIDFIS (thanks a MILLION jeff20b) and now my plugs are actually partially brown instead of black and sooty, partly black still, but either way a step in the right direction. I also found out that my secondaries werent opening for two reasons.... first, turned out the butterflies were actually hitting the intake manifold, some grinding stones and some porting on the primaries on the manifold took care of that. but they still werent opening while driving, they would if you cranked the throttle wide open by hand, turns out that my gas pedal wasnt moving the throttle quite far enough to get WOT unless you practically stand up on it when you are in the car, so if I try to push the pedal through the floor instead of to the floor, they open and my god they are loud! (thank god, hehe) anyway, even though they are now opening, it just makes noise with no difference in acceleration, its pulling higher rpm than before, and at high rpm, it starts cutting out, how would I best determine if its fuel starvation or the ignition cutting out?
Hey thanks! By the way, have you installed a relay to get true battery voltage to the ignitors and coils? Or is it still sucking power through the old stock ignition switch wires? I just installed a relay in my white REPU today and it seems to feel more powerful. I also didn't notice anymore blips at idle, although I wasn't specifically looking for any (if they're still there, at least they didn't grab my attention as they often do every now and then). May tach didn't bounce with the headlights on anymore either. A relay completely cured the idle blips in my red REPU. The next relay project is my '76 CD Cosmo.
At high RPM, there is obviously a higher electrical load since there are more ignition events per second than at idle, but the alt is also spnning faster as well (a slow spinning alt at idle may have been where the blips came from in my red REPU). Either way, if you had a way to directly monitor the voltage level at the ignitors and coils while driving, it would let you know if you're having a bit of a brown-out at high RPM.
Do you have a fuel pressure guage? If you can install one on an unused port in your FPR (fuel pressure regulator), and tape it to your windshield, it'll tell you if you have fuel starvation at high RPM.
At high RPM, there is obviously a higher electrical load since there are more ignition events per second than at idle, but the alt is also spnning faster as well (a slow spinning alt at idle may have been where the blips came from in my red REPU). Either way, if you had a way to directly monitor the voltage level at the ignitors and coils while driving, it would let you know if you're having a bit of a brown-out at high RPM.

Do you have a fuel pressure guage? If you can install one on an unused port in your FPR (fuel pressure regulator), and tape it to your windshield, it'll tell you if you have fuel starvation at high RPM.
Thread
Thread Starter
Forum
Replies
Last Post
alphawolff
1st Generation Specific (1979-1985)
17
Nov 17, 2015 05:57 PM
Captain_Panic
Alternative Fuels
9
Sep 16, 2015 02:06 PM
sip
3rd Generation Specific (1993-2002)
19
Sep 7, 2015 03:33 PM




