Common questions

What to do if there is no injector pulse?

What to do if there is no injector pulse?

If after all this you got the same result, so it’s time to check the injectors itself if there is no injector pulse on one cylinder, by try to unplug injectors one at a time, if the engine starts when a particular injector is unplugged so that it is the defected one that needs to be replaced

Is there an injector pulse while cranking the engine?

The engine will run if you either spray starting fluid down the throttle body or hook up a remote start switch. If you use the key, there is no injector pulse while cranking. As you let go of the key and return it to the run position, the injectors give one squirt.

How does the engine control unit control the injector pulse?

Question: What controls the fuel injector pulse? Ans: The engine control unit is the electronic brain that used to control the fuel injector pulse by gathering data from various sensors along the fuel line

What causes no power to fuel injectors?

The most important signals that determine the accuracy of a signal coming out of ECU to injectors are crankshaft position sensor and camshaft position sensor, so to test a bad injector, you have to check the voltage on the injector when the ignition key is turned on: NO VOLTAGE? , so what causes no power to fuel injectors?

Why is there no pulse from the injector?

Used all original electronics and tbi. New wires, plugs, cap, rotor, fuel filter,etc… have spark, have fuel at the back of the tbi. No pulse at all from either injector?

What kind of signal does a GM injector pulse have?

Purple/white wire with key on had barely any signal at all. Wires to the injectors have 12v with key on. I have fuel at the rear of the tbi but not sure of the pressure?

What kind of meter do I need for injector pulse?

I pulled the four pin connector from the dist. all I have is a standard radioshack volt meter. Purple/white wire with key on had barely any signal at all. Wires to the injectors have 12v with key on. I have fuel at the rear of the tbi but not sure of the pressure?

Question: What controls the fuel injector pulse? Ans: The engine control unit is the electronic brain that used to control the fuel injector pulse by gathering data from various sensors along the fuel line

If after all this you got the same result, so it’s time to check the injectors itself if there is no injector pulse on one cylinder, by try to unplug injectors one at a time, if the engine starts when a particular injector is unplugged so that it is the defected one that needs to be replaced

When to turn off glow plug on diesel engine?

You should always wait for the light to shut off before attempting to start the engine. Being a little patient will help keep your engine going strong in the long run. Our certified technicians are always available if you ever require assistance identifying glow plug issues.

When does the glow plug light come on?

Once the correct temperature has been achieved, the computer will then let the driver start the engine. Normally, the glow plug indicator light will come on only when the engine is cold. Typically, this light flashes only when an issue has been detected. The most common reason to replace glow plugs is age.

What happens if the powertrain control module is not working?

The fuel injectors are responsible for allowing fuel to be injected into the cylinders and the timing of these injectors are controlled by the ECU. If the ECU is not working, then the valves on the fuel injectors may stay closed which will prevent fuel from entering the cylinders. What are the symptoms of a bad powertrain control module?

What causes no power to fuel injector pulse?

Ans: The engine control unit is the electronic brain that used to control the fuel injector pulse by gathering data from various sensors along the fuel line Question: What causes no power to fuel injectors?

The fuel injectors are responsible for allowing fuel to be injected into the cylinders and the timing of these injectors are controlled by the ECU. If the ECU is not working, then the valves on the fuel injectors may stay closed which will prevent fuel from entering the cylinders. What are the symptoms of a bad powertrain control module?

Can a bad ECM cause a car to not start?

Of course, there are other reasons a car may not start, including a bad starter or a blown alternator. If you’ve replaced these parts and your car won’t start, your ECM is the most likely cause. Once again, you’ll need to take your car to a mechanic to be sure.

Can a multimeter be used to check fuel injector pulse?

Therefore, you can see that having a well-functioning fuel injector is vital, and there are numerous reasons why it might stop working correctly. In this article, you will be taken through the steps you should follow to check the fuel injector pulse using a multimeter before you decide to make use of an injector cleaner.

Where is the prom access cover on a 305 engine?

It used a small box mounted right above the ECM called the Mass Air Burnoff Module. This ECM can be easily recognized by having the PROM access cover at the top of the unit, and has only two harness connectors. This ECM was used both on 305 and 350 engines. Depending on the engine size however, it used a different PROM, and a different CAL-PAK.

Is there an injector pulse on my car?

SOLVED: I have no injector pulse. I have plenty of fuel – Fixya I have no injector pulse. I have plenty of fuel pressure and both crank sensors and the cam sensor are good. If I spray carb spray through a vacuum hose, it runs fine, but I’m getting nothing through the injectors.

How does an injector work on a PCM?

Injectors do run off both crank and cam sensors, but mostly off the cam. And when the cam sensor does fail, The PCM goes into default mode, using the last stored run. Just a note… when you find the injector fuse pull it out, sometimes fuses just loose connection. You can’t post conmments that contain an email address.

Why does my carb spray have no injector pulse?

I have no injector pulse. I have plenty of fuel pressure and both crank sensors and the cam sensor are good. If I spray carb spray through a vacuum hose, it runs fine, but I’m getting nothing through the injectors. What else besides the PCM would control the injectors other than the cam and crank sensors?

Where is the injector pulse on an ECM?

Okay ecm fires injectors with ground…should have a set of ground wires at thermostat..and one on intake behind where ac pump is or should be. Make sure clean and connected tight.

Where does the injector pulse come from in a truck?

I guess no one reads….injector pulse comes from ecm..via ignition module..pickup coil.Once ecm senses 400 rpm,s from engine it takes over. But injectors pulse works off of ground from ecm…you have to have the grounds at thermostat and intake or will not pulse injectors.Grounds for all sensors.

How do you test a fuel injector ( ANS )?

Ans: By using a simple diagnostic tool called NOID light, this tool detects a digital signal coming from the ECU and flashes an LED light, so if there is no LED flashing during cranking, this means that there are no pulses coming out of the ECU. Question: How do you test a fuel injector?

How to solve ” I have no injector pulse “?

An expert that got 5 achievements. Re: I have no injector pulse. I have plenty of fuel… There is an injector fuse. Pull an injector plug , 1 wire should have 12 volts to it. the other goes to the PCM. The PCM is set up so that it has individual injector drivers, Meaning that you could loose 1 or 2, but loosing all 6 at one time is very unlikely.

Can a PCM loose all 6 injectors at once?

The PCM is set up so that it has individual injector drivers, Meaning that you could loose 1 or 2, but loosing all 6 at one time is very unlikely. Injectors do run off both crank and cam sensors, but mostly off the cam. And when the cam sensor does fail, The PCM goes into default mode, using the last stored run.

The most important signals that determine the accuracy of a signal coming out of ECU to injectors are crankshaft position sensor and camshaft position sensor, so to test a bad injector, you have to check the voltage on the injector when the ignition key is turned on: NO VOLTAGE? , so what causes no power to fuel injectors?

Is there no fuel from injectors to start truck?

No fuel from injectors to start truck. When I try and start my 93 Chevy Cheyenne k3500 no fuel come out of the injectors. If I use starting fluid the truck starts and the injectors work great. Has died a couple times while driving, but mostly runs fine and then won’t start one turned off.

What causes PCM to disable fuel injectors?

@jrt2020 , Josh, The anti-theft system (Pass Lock) failure will mimic this, as anti theft tells PCM to disable the fuel injectors.

How can I test the resistance of my injector?

Another way to test the injector is to measure the resistance of every injector between the two terminals and compare it with the highest and lowest values stated in the injector datasheet; if the result outside the allowable boundaries, then change this injector.

How much does it cost to replace a failed injector?

A diagnosis of a “failed” injector can cost thousands of dollars in replacement costs. However, a closer look at the problem reveals an interesting insight. Since the introduction of the 7.3 L Power Stroke in 1994, injectors have been relying on oil pressure to fire the piston via the HEUI fuel system.

No fuel from injectors to start truck. When I try and start my 93 Chevy Cheyenne k3500 no fuel come out of the injectors. If I use starting fluid the truck starts and the injectors work great. Has died a couple times while driving, but mostly runs fine and then won’t start one turned off.

When to replace an injector after failure code is triggered?

Frequently mechanics recommend replacing the injectors after the failure code is triggered. This is where the myth comes into play. While it is true that a replacement will solve the problem of an injector not performing correctly due to stiction, it is often unnecessary.

How to know if your engine has no spark?

First Confirm Your Engine Has No Spark. 1 Disable the fuel system by removing the fuel pump fuse or relay. 2 Insert a spark plug tester into the plug boot and ground it on a piece of metal on the engine. 3 Finally, Have someone crank the engine and watch for spark.

Why does my car not start when I crank the engine?

The crankshaft position (CKP) sensor monitors the position or rotational speed of the crankshaft. If the crankshaft position sensor has failed completely, and isn’t sending a signal to the (ECU) at all, then the computer won’t send any fuel to the injectors. This will leave you unable to start the car.

First Confirm Your Engine Has No Spark. 1 Disable the fuel system by removing the fuel pump fuse or relay. 2 Insert a spark plug tester into the plug boot and ground it on a piece of metal on the engine. 3 Finally, Have someone crank the engine and watch for spark.

Why does my car not start when I push the start button?

False input or lack of input from sensors like the crankshaft position sensor (CKP) or camshaft position sensor (CPS) can prevent the engine from starting. Also, a bad throttle position sensor (TPS) may cut off the spark to the cylinders.

What to do if you don’t see a spark in your spark tester?

While watching the spark tester, have an assistant crank the engine. You should see a bright spark jumping the gap in the spark tester. If you don’t see a spark, repeat the test. This time, adjust the spark tester to 30KV. If still you don’t see a spark, repeat the test and set the tester to 10KV.

Why do my injectors stop firing during crank?

Injectors will fire during crank and 1-2 secs later will stop after most of these situations, excluding a security problem, they wont fire at all, but may show pulse on the scanner. If you have a fueling tune problem or other, then your injectors will still show to be pulsing… so post a log.

What to do if your fuel injection is not working?

However, before looking for the problem in the fuel injection system, make sure that it is not possibly in another part of the engine, such as in the ignition system. Engine does not start, fuel pump is not running. Defective pump connections, pump relay or connections. Check pump connector for good condition.

What happens to fuel injector when engine is shut off?

Fuel injectors deliver fuel to the combustion chamber directly or indirectly. During its evolution; the fuel injector has moved from the intake manifold to the combustion chamber. Over time the nozzle of the injector can become dirty; and partially blocked. When you shut off your engine; the injector will soak up the heat of the engine.

How can I tell if my fuel injectors are working?

These are all, fuel & air metering injector circuit related codes. Another helpful diagnostic tool is an engine stethoscope. This tool enables a car owner, to listen for any problems with the fuel injectors; by placing the tip of the stethoscope on each injector. Fuel injectors make a sharp clicking sound, when they are functioning properly.

Where is the spark in an ignition system?

Electronic ignition pickups are a component found on traditional electronic distributor ignition systems. They are located inside the distributor and function as the trigger for the ignition system to produce spark. The pickup coil monitors the rotation of the distributor and triggers the ignition system.

Why is my no injector pulse but does spark?

In relation to your no injector pulse problem, check the wiring harness from the distributor to the ECM. If that harness has become disconnected somehow, the ECM will not have a pulse reference from the distributor in order to fire the injectors. Also, make sure that you actually have power to the injectors, as there are 2 fuses that supply them.

Ans: By using a simple diagnostic tool called NOID light, this tool detects a digital signal coming from the ECU and flashes an LED light, so if there is no LED flashing during cranking, this means that there are no pulses coming out of the ECU. Question: How do you test a fuel injector?

What happens if there is no injection signal?

The ECU cannot pulse the injector without an Ne signal and will not start or run if this signal is not present. If the G signal is not present while cranking the engine, the ECU will not be able to identify when to produce the injection signal. The result will be the same, no injection pulse.

What happens if I unplug the rear wheel sensor?

After a lot of looking and trial and error, I unplugged the rear wheel sensor and the problem stopped. My question is, since I unplugged the sensor do I still have all-wheel braking? A: If your ABS (or at least the system on your Buick) packs up, you’ll still have brakes on all four wheels, but without the benefit of the antilock feature.

What are the symptoms of a bad injector control pressure sensor?

Cost of Replacing a Bad or Failing Injector Control Pressure Sensor. Common signs include starting issues, engine misfires, the Check Engine Light coming on, and a decrease in power, acceleration, and fuel economy. Our certified technicians can come to you and diagnose the problem.

Can a check engine light set off an injector control sensor?

An illuminated Check Engine Light can also be set off by a wide variety of other issues, so having the computer scanned for trouble codes is highly recommended. Injector control pressure sensors are more commonly found on diesel engines, however they can also be found on vehicles equipped with gasoline engines.

What are the symptoms of an ECU failure?

Many other symptoms may occur that can drastically lead to an ECU failure such as: 1 Erratic idle 2 Stalling 3 Poor running condition 4 Excessive fuel usage

How to diagnose your engine control unit ( ECU )?

Videos you watch may be added to the TV’s watch history and influence TV recommendations. To avoid this, cancel and sign in to YouTube on your computer. An error occurred while retrieving sharing information. Please try again later. These are some examples of the damages that we see on most ECUs:

How are fuel injectors fired in a DSM ECU?

The DSM ECU uses sequential firing of the injectors most of the time, we have injector drivers for each injector. It’s not a batch fire setup except when cold starting and under acceleration enrichment. The DSM ECU uses sequential firing of the injectors most of the time, we have injector drivers for each injector.

Can a car injector be pulsed on a multimeter?

With the car running, it may be hard to see because multimeters are so slow, but you should get a pulsed battery voltage. It will probably just show up as a constant voltage on the multimeter however. If you don’t get it, the injector isn’t being pulsed. Now, since it’s only the number 2 injector, it shouldn’t be the injector driver in the ecu.

What causes low ICP on a Ford PowerStroke?

1. Refer to other hard start or no start issues below 2. IPR (Injection Pressure Regulator) bad, will cause low ICP. Buy 7.3 IPR Valve 3. IPR o-rings bad, will cause low ICP. Buy IPR O-ring kit for 7.3 Powerstroke 4. Injector o-rings bad, will cause low ICP. Should also show up as black fuel (from oil in fuel) in fuel filter canister.

Another way to test the injector is to measure the resistance of every injector between the two terminals and compare it with the highest and lowest values stated in the injector datasheet; if the result outside the allowable boundaries, then change this injector.

Why is my TFI and injector pulse not working?

Mar 10, 2000 The PIP is indeed suspect. Pull the SPOUT jumper out of the harness and see if it makes a difference. Keep in mind that PIP problems may be heat sensitive, and the symptoms may change as things cool off. The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors.

Where are the fuse links on an 86-93?

86-93 models only: Fuse links in wiring harness – look for 12 volts at the fuel injector red wires. All the fuse links live in a bundle up near the starter solenoid.

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Ruth Doyle