NEED ECU 2001 MODEL NOT PULSING ON NO2 INJECTOR

The injector pulse is fed from the ECU and the signal is fed from the crank sensor. The only things to check are the sensor, the ECU or the ground.

injector pulse from ECU

the ECU will have fault codes stored internally to find the cause

would check other sensors first
crank angle sensor or cam angle sensor could stop the pulse
immobilizer

if the engine cranks over and has spark
ignition would be the last thing i would checkout

Cud b voltage issue. Unplug them and clean contacts. Also u cud unplug computr and clean pins . Older cars have corrosion

blown fuse. ; is first, as per always.
2nd is scan it, did you scan it yet? that is always 2nd.
all efi engines, all ECU , all cut injectors for (noid lamp test dead?)
you said pulse,does that mean fuel pulse or electronic pulse to injector coil..... ? all injectors dead. or just 1. same for spark.
toss coin land, noid dead. all noids
loss of. NOID signals.!
1; spark
2: lose of CMP or CKP signals (cam or crank senders)
3: ecu sees wide open throttle it cuts fuel 100%
4: ecu bad, is CEL lamp dead key on? scan it.

The signal is generated by the engine computer. If the singal is intermittent, check the wiring harness. It ispossible for the comouter ("ECU") to fail like that but that is not likely. Could be the injector is shorting out internally after it gets hot. The porblem is called a "shorted turn" and the only solution is to replace the injector.

Injectors are sold in "matched sets." The ECU assumes each injector quirts the same volume of fuel per pulse. Replacing one injector could result in that cylinder running a bit more lean or rich. UNless you race your vehicle any fuel injector imbalance will likely be unnotable.

If ECU has crank signal and engine turns over, ECU should give injectors a pulse and trigger the ignition. If not ECU might be bad. You should check power and grounds going to ECU. There are usually multiple power and grounds going into ECU

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check the ground side of injectors and wiring to ecu a ground pulse from ecu fires the injectors

Have you tried reading the trouble codes from the ecu to see what's actually gone bad? A bad crank sensor will not allow the ecu to pulse the injectors and spray fuel.

Hi I have a 1995 C200 Auto Sedan chs WDB 2020202F241703, I think I have a problem in the ECU. Only runs on two cylinders, I have changed the core pack on the 1 & 4 cylinders but the problem persists. The other problem is I don't know where the ECU (engine computer ?) is can anyone help ?

What is the impedance of the injectors? If it is too low or the pulse causes the solenoid in them to move and there is a short when it moves, then the ecu wont fire them again.