What causes no pulse to injectors?

what does pulse mean, scope or NOid test lamp dead on injector
or the injector tips do now spray when engine is cranked
we can not see you doing the tests and matters.


symptoms. my guess African car, and no engine told, gas/petrol not told
sizes in CC or liters. 4cylinders? (roller cam sure)
2006 is GEN 3.
wiki says it is
1,297 cc and 1,597 cc Rocam (Roller Finger Camshaft)
1.3 or 1.6L which one? SOHC
Brazilian-designed Rocam engine is of single overhead-cam configuration with two valves per cylinder.

dead engine, cranks fast right but engine is dead, will not start or stay running.
won't start with quick start spray works, but will not stay running,
seems it has spark (spray works and sounds good)
starts but will not RUN, (spray lasts for 3 seconds)

so is the cam belt ignored and now slipped (if has belt, no books here)
all fuses, good
scan the PCM for DTC error test

the PCM cuts fuel (injectors) for many reasons, for sure to not catch fire.
1: all fused checked for good in all fuses boxes. as in ALL.
2:no real engine told or country told so folks can help with more exact answers
causes, injection dead ( but PCM fires them with electrical pulse)
top cause fuel pressure not to spec,
the crack a line dribble tests are no good. if dry yes but dribble tests mean zero.
the PSI (BAR)_ pressure must be at spec to the fuel rail.

that is one answser, now lets to , injector all 4 pins have no electrical pulse using noid test lamp or scope see the super fast pulse there, 5mS (0.005 seconds)
that cause is, PCM sees spark dead even if spark is good
the PCM seens throttle by wire dead if present, (no books in USA for bantam)
PCM sees CMP or CKP sensor errors, cam or crank sensors.
PCM sees IMMO failing (security key if has it)

now answer 3.
the engine compression is not 150psi and up tested. 10Bar up, not less.
on all 4 cylinder, and near even.

EGR stuck open
CAT core melted and now engine can not pump air, or run.
lots of test to do .
but I bet fuel pressure is wrong, at the rail 30psi up. for most cars
I have no PSI spec, 2bar up. fuel pressure. not zero not 1. but 2 up.

Sounds like they're (not their) stopped up.. time for removal and cleaning...if you are a good. competent mechanic,witht he necessary tools you can do this!
Get one of these before you start!!
Ford 150 1980 1996 Repair Manuals

check the inectors, a cracked/failed injector will cause over fueling and bog the motor down.

Spray starting fluid or carb cleaner into the air intake to see if it really is a fuel problem. If it tries to start, like firing for a few seconds, it is probably not getting gas to the cylinders. Then you need to check the injector circuit. If fuel is getting up to the engine, then the pump is working, but maybe not good enough-check that by testing the fuel pressure. Hook up a fuel pressure gauge to the fuel rail, turn key to on, and you should see high pressure on the gauge, about 50 psi, but check for manufacturer specs for the correct pressure.

The injector circuit uses a fuse for the injectors, then it applies constant voltage to the injectors when the key is in on or run or start. See if you have voltage to the injectors with the key on. The injectors will pulse when the pcm momentarily grounds the injector circuit-it grounds each individual injector internally inside the computer for a split second. This causes the injector solenoid to energize and raises a pintle inside the injector so that fuel under pressure will spray out into the cylinder.

a crank position sensor will cause no injector pulse check out

the misfire may be caused by a fuel injector that is not working. Do you have a good spark at that cylinder?. If so try the redneck approach to fixing a stuck fuel injector. first make sure the fuel injector plug is clean(terminals) and on tight. With the engine running, Take a long socket extension and place an end on the fuel inector plastic housing, tap on the other end with a hammer. LIGHT taps!!! remember its just plastic! sometimes this is enough to free up a stuck injector. If not, then replace the injector.

before you do this Unplug the injector and see if the engine idle changes. Also check for an electrcal pulse at the injector plug with engine running.

Check all injectors with a needle stethoscope. Unplug electrical connector of bad injectors, and check the signal with (injector check light). The light must pulse. If not might be a bad computer. If yes replace bad injectors with new one. Hope will help.
This is a free advice. Do not rate me.

When the ignition switch is turned on the pcm turns on the fuel pump by energizing the fuel pump relay. The PCM keeps the fuel pump on as long as the engine is cranking over or running.It does this by recieving pulses from the ignition module. If there are no referance pulses the PCM will turn the fuel pump relay off in 2 seconds with the ingnition on.

Most models also include a secondary control path through the oil presure switch witch will turn the fuel pump on after it detects oil presure.cranking time will be longer if the fuel pump doesn't recieve current until oil presure switch contact is closed.

Is there an injector pulse going to the injector?(an electrical pulse to fire the injector).
Is there spark at the plugs?
If the pickup in the dist is faulty you won't have either one.
If your vehicle uses a crank pickup with or instead of dist pick up....if it is defective ....no pulse.
The above is 90% cause of no pulse....other is computer problem 10%.
If you do have a injector pulse and no spray.....and have fuel pressure....change the injector.
A quick check for spark is spray a little starting fluid in it.....if it starts on the fluid....spark is present.

check for a bad crank sensor for this controls the timing of crank shaft. and sends info to pcm. it will cause no spark or pulse at injectors.the engine may start but cut out in a few minutes or seconds, of operation. have the car scanned for the problem code, if no scanner, any auto parts store will scan for free. good luck !!