08-16-2020, 01:14 AM
Hello all, new to this forum but have been reading a ton, thx for all the info!
Backstory: Driving along and suddenly engine died. Spark test - pass, Fuel pressure near 50 psi at intake, basic NOID test, failed. Replaced caps on ECU. Still no NOID pulse. Did more extensive testing, TPS good, injector at 1ohm, wiring good from ecu to harness at TBI. Here are where my questions begin.
Doing the pulse signal tests on positive side (red wire), I get no signal, key on dead, turning over no signal.
Doing the test on negative side (yellow wire) I get no signal, key on dead, turning over dead.
I'm pretty convinced one of the transistors is bad. Curious if there is an simple DMM test I can do on the transistors to determine if one is bad? If the plus side (red wire, B8, Q101) transistor is bad will this always kill the signal on negative side? Is it both work or both fail?
Trying to do as much testing as I can before I go the route of replacing the transistors. Thanks for any input!
1992 Samurai TBI 8v
-80CXX ECU
Backstory: Driving along and suddenly engine died. Spark test - pass, Fuel pressure near 50 psi at intake, basic NOID test, failed. Replaced caps on ECU. Still no NOID pulse. Did more extensive testing, TPS good, injector at 1ohm, wiring good from ecu to harness at TBI. Here are where my questions begin.
Doing the pulse signal tests on positive side (red wire), I get no signal, key on dead, turning over no signal.
Doing the test on negative side (yellow wire) I get no signal, key on dead, turning over dead.
I'm pretty convinced one of the transistors is bad. Curious if there is an simple DMM test I can do on the transistors to determine if one is bad? If the plus side (red wire, B8, Q101) transistor is bad will this always kill the signal on negative side? Is it both work or both fail?
Trying to do as much testing as I can before I go the route of replacing the transistors. Thanks for any input!
1992 Samurai TBI 8v
-80CXX ECU