Skip the auto shop - Our mechanics make house calls

Q: Tbi problems

asked by on

My son recently hooked the battery up backwards. Luckily, i yanked it out of the vehicle before the fire would've started. Now... the tbi isn't receiving any fuel. New pump, sending unit, relay, lines, and ecm. Have spark, pressure at the throttle body, and fuses are good. Injectors refuse to spray. Why? I NEED this truck to work. NOW.
My car has a manual transmission.

A: The fuel injector is a simple part. You can...

The fuel injector is a simple part. You can test the injector by giving it power and ground. If there is fuel pressure, it will spray for as long as you hold the power on. You can also check the electrical resistance. It should be around 1.5 ohms.

The injector receives power through the ECM fuse. It should have power with the key in the run and start position. The ground comes from the ECM. You will need a noid light to test the ground pulse from the ECM.

There are several fusible links to check too. The smaller wires connected to the starter battery pole are powered at the starter. That's where the fusible links are. Pull on them to test. If they are flexible, they are blown.

How did you check your fuses? They should have been checked with a test light to verify they are powered.

If you need more help, consider YourMechanic, as a certified technician can help you with your fuel injectors and pinpoint any other problems your car is having. We come to you.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Car cutting off while driving

This could be a fuel delivery issue, but it is hard to say exactly. Your vehicle has a complex engine control system that can self diagnose issues most of the time. Start by having the computer read and see if...

Q: AC light on dash

GM has a TSB out for this issue. If the system is full, then the negative battery terminal needs to be disconnected to reset the climate control computer. If the system does not work after this, then gauges will need...

Q: LED lights and radio, air stay on and drain battery

Parasitic draws can be difficult to pinpoint at times. If the door lock is only working with the key, it sounds like the most likely cause is the door security control not working properly. The vehicle waits for all doors...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...