Q: nissa d21 z24 carburated strange rattling noise

asked by on June 20, 2016

I am the owner of a 1987 Nissan 4x4 d21 z24 carbureted. First of all, the engine has been completely rebuild, new pistons and everything related to that , new head and gasket , new valves , and new timingchain/kit. , etc etc..... I swapped out the old carburetor with a much better , (rebuild one). The problem from the beginning was that the engine could not stay idle, at least not at 8-900 rpm as it should. at 1000 rpm and above idles fine. And from the begining i had this rattling noise from the engine , not at startup , but when i release the gaspedal after acceleration and kept the gaspedal in the midrange (cruising). no specific rpm. When i accelerate and braking with engine no rattling noise , only with gaspedal in midrange, (sounds like a dieselengine).

My car has 107000 miles.
My car has a manual transmission.

Hello. In regards to your idle speed issue, I would recommend tuning and adjusting the carburetor until the correct idle speed is achieved.

As far as the rattling noise goes, firstly I would check to make sure that the engine has adequate oil, and that it is clean, as the tensioner, as well as the valve lifters on that engine, use oil pressure to work. If they are starved for oil, for any reason at all, it can compromise their ability to do their job.

The rattling noises you are experiencing may be either a result of a loose chain, perhaps due to an improperly functioning chain tensioner, or perhaps lifters. If your vehicle is turbo, I would also double check to make sure that you have no vacuum leaks, and that your turbo diverter or recirculation valve are functioning properly.

If you need assistance with this, feel free to contact a certified mechanic who can pinpoint the rattling noise in your engine and make the appropriate repairs to get your engine running normally once again. Good luck.

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 you use the cargo net?
If your Altima is equipped with a cargo net, this handy tool can be used to secure packages in the trunk. Not only is this handy for keeping packages with fragile items inside from sliding around in the back, but...
Camper taillights not working
The first thing to check is for power at the trailer plug on the truck. Use the ground within the plug to check it as well. There might be separate fuses for the trailer lights. If it is ok the...
Left cap off-check engine light won't go off
Hey there. After a few ignition cycles - started, driven, and shut down - the code should erase itself if the ECU no longer sees the loose gas cap as a continuing fault. There shouldn't be any drivability problems if...
My 2008 Saturn Vue has lost power steering briefly twice on right turns. The fluid was checked no leaks.
Hello. If you are losing power steering on turns, then you may have a belt tensioner issue (https://www.yourmechanic.com/services/drive-belt-tensioner-replacement) causing the power steering pump to have low pressure when turning. Have the belt and tensioner checked (https://www.yourmechanic.com/services/steering-wheel-does-not-respond-properly-inspection).
2002 duramax went into limp mode after fluid ad filter change
Hello, I can help you with this! When doing a transmission service for this vehicle, you will set a (DTC) trouble code for a low pressure condition with transmission. This is a normal condition when replacing the filter and...
Will they test the alternator to make sure it needs to be replaced?
Hi There, It sounds like you may potentially have a faulty voltage regulator or alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting...
Losing power when i mash gas petal runs ruff
Hello, This may be a problem with fuel pressure or potentially a dirty or faulty mass air flow sensor. The mass air flow sensor (https://www.yourmechanic.com/services/mass-airflow-sensor-replacement) monitors air intake as it is mixed with fuel prior to being injected into the...
My car makes a chirping noise while in motion, the noise is more frequent based on how fast I'm traveling.
You should have the brake sensors checked to see if the brakes are worn to the sensor or the backing vent plate is rubbing the rotor. If both are good then you may have a front wheel bearing then is...
Starter connecting bracket
This would depend on if the starter itself is loose or not. If the starter is still starting the vehicle just fine and does not appear to be loose, you should be able to get by for a while. However...

Related articles

A Buyer’s Guide to the 2012 Nissan 370Z
Whether Whether you opt for the roadster or the coupe in the 2012 Nissan 370Z, you will be choosing a machine that will provide outstanding performance and a luxurious interior that you won’t be able to tear yourself away from....
The Best Used Cars to Buy For Fuel Economy
Saving money on gas is an important factor to consider when buying a car. The Honda Civic, Toyota Prius, and Ford Fusion all have great fuel economy.
Symptoms of a Bad or Failing Catalytic Converter
Common signs include reduced engine performance, rattling sounds, and the Check Engine Light turning on.