Q: Truck is running rough, loses power, backfiring noise - 1994 Nissan D21

asked by on September 14, 2016

Lately, my truck has started to run rough and seems as if it would shut off. After I had the fuel filter replaced, it was better for a while. However, the truck now can barely run, even more so when I try to increase the speed and the RPMs are higher. It seems to lose power and makes a backfiring noise. It also gets very bad gas mileage. What should I do?

Fuel Pump Replacement $145.32 - $1299.70 Get a Quote
Fuel Injector Replacement $400.56 - $3968.30 Get a Quote
Loss of power Inspection $94.99 - $114.99 Get a Quote

Hey there. I would check fuel pump output and condition of fuel injectors (flow rate and solenoid resistance). After that, I would evaluate the ignition system, including distributor, plug wires, timing. If you would like to have this checked for you, a certified technician from YourMechanic can come to your car’s location to inspect the loss of power symptoms and help get your car back in running shape.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

How do I turn on the parking lights?
To turn on the parking lights, first locate the turn signal lever, which protrudes from the left side of the steering column. Then, turn the Light switch to the headlights position. This will turn on the parking lights, as well...
How do I scroll through the radio stations?
Scrolling through the radio is very easy. Simply press the Tune soft key, then use the Left/Right buttons to scroll (press the button a second time to stop scrolling), or rotate the Tune knob.
Turn signal doesn't turn off after making turn
Hello. The problem is the cancellation spring located in the turn signal arm. This spring makes contact with the high spots in the column when the steering wheel turns. These high spots hit the spring and cause it to return...
Check gauges light is on and car won't start - 1990 Chevrolet C2500 Suburban
Hello. Most of the time, the symptoms you are describing are caused by the battery failing (https://www.yourmechanic.com/services/battery-replacement). If there is a bad connection at the battery or if the voltage in the battery is low, then this will occur. If...
My car shakes when it gets up to about 60 miles per hour feel like the tire is going to fall off
This may be caused by a variety of possibilities, however, I would start with checking tire pressure in all the tires checking to be sure the lug nuts (https://www.yourmechanic.com/services/tighten-wheel-lug-nuts) on every wheel are tight and checking for any bubbles or...
Car not overheating but I have coolant boiling in the reservoir tank. I have to add about a quart of coolant to the radiator ever
If you are getting low on coolant and have bubbles going into the overflow bottle then you most likely have a blown head gasket. It does not always put out smoke from tailpipe. You will need to have system pressure...
95 nissian maxima have replaced fuel pump, crank sensors both still car stalling and sometimes won't start
Hi Sonja. Thanks for contacting us today. Usually when a fuel pump or crankshaft sensor is not working, the vehicle will not start at all. It's more likely that you have a fuel system restriction or the engine is having...
Engine cuts off
Engine heat can degrade components such as ignition coils and the crankshaft position sensor. The components will then fail once they are hot. There are other possible causes of the stalling, too, such as the fuel pump relay opening or...

Related articles

A Buyer’s Guide to the 2012 Nissan Frontier
When When looking for a truck, the 2012 Nissan Frontier could be the vehicle you’ve been hunting for. It has a great look, a strong engine, and it is reliable. The vehicle has been making gains on other trucks in...
The Best Used Cars to Buy If You're an Archeologist
If If you are an archaeologist, you need a vehicle that will take you off the beaten path. After all, that’s where you spend a good deal of your time. And that means that you will need, ideally, an SUV...
The Best Used Cars to Buy If You’re a Vet
The The best car for a vet to own largely depends on the type of practice he or she has. Large animal vets are probably going to want something that delivers a fair bit of power, and possibly even towing...