Q: no pulse on injector so not getting any gas

asked by on

not getting any gas in tbi put in new ecm but still no pulse
My car has an automatic transmission.

Three things are needed in order for the injector to spray fuel: 12 volts from the ECM fuse, ground from the ECM, and fuel pressure.

A simple check to test the injector and fuel pressure is to provide 12v and ground manually to the injector. You should hear it click and fuel should spray.

  • Warning: Be careful! Connect the injector side first to prevent a spark near a fuel spray.

You’ll have to cycle the key to prime the fuel system to do this more than once. If it does not spray, the problem is the injector or no fuel pressure. The injector should have around 1.3 ohms of resistance, if it is open or zero resistance, it is bad. The injector could be totally clogged as well. Fuel pressure should be 9 to 13 psi.

Check the wiring to the injector. You can check the positive side with a test light with the key on. If that is good you will need a noid light to check the negative pulse from the ECM. A test light will not work for this. Connect the noid light, and crank the engine. If it blinks, the wiring is good.

Did you check the spark on this engine? If there is no spark as well, the pick-up coil in the distributor is the most likely problem. This tells the ECM how fast the engine is turning. No pick-up coil input, no spark or injector pulse.

If the pick-up coil is the problem, you might be better off replacing the distributor. You have to disassemble the distributor to replace the coil. This can be difficult due to carbon and sludge baking on the the distributor shaft. Plus, you will get a new ignition control module as well. If you need assistance with this diagnoses and repair, reach out to a certified mechanic who will be able to replace your distributor and fuel injector if necessary.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. no pulse on injector so not getting any gas

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Boots on spark plug wires keep melting 1995 Chevrolet S10

Hi there - this is a problem with this engine, and the stock exhaust manifolds come with heat shields to help prevent the burned plug wire problem. Perhaps your heat shields have been removed? Or, if you're running headers, using...

Q: Q: Transmission not engaging

Hello. If the shifter is moving fine and the truck responds to the shifter position but does not move when the transmission has more than likely failed. If there is no response at all, then it may be the shift...

Q: Drive belt keeps popping off

The first thing to check is whether all of the pulleys are in the same plane. Imagine a flat surface applied up against the pulley edges. Do all pulleys touch the flat surface? If a pulley, for instance, on the...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...