5.7 Hemi Cylinder Deactivation Solenoid Location (The Ultimate Guide)

5.7 Hemi Cylinder Deactivation Solenoid Location

Cylinder deactivation technology is used in most performance engines to enhance fuel economy. In this technology, when the cylinders are deactivated, the engine turns off the ignition source for the cylinder and the engine starts using less fuel.

But to make this happen valves equipped with the cylinders must be closed and later the fuel needs to shut off. Check 5.7 Hemi Oil Control Valve Location

And to do these things you require a piece of knowledge about 5.7 Hemi Cylinder Deactivation Solenoid Location. Without it, you can’t find out the valves and fuel switch to close them and thus this technology will be unused on your engine.

Therefore, your engine won’t increase fuel economy and eventually, it will wear out pretty soon. So, you just need to get proper knowledge about 5.7 Hemi Cylinder Deactivation Solenoid Location to use cylinder deactivation technology. 

What is a cylinder deactivation solenoid?

When your engine is fitted with cylinder deactivation solenoids, then it can detect the car is cruising or not. A solenoid valve turns on and a system forces that valve to turn off. It also prevents air and fuel from reaching a few cylinders.

Therefore, combustion will take place in half of the engine and the reason behind is the less burned fuel while cruising. This entire process is known as a cylinder deactivation solenoid. 

How to replace cylinder deactivation solenoid?

To replace cylinder deactivation solenoid, follow the below-mentioned steps properly:

  1. Find the fuel injectors and open them properly.
  2. Remove the EGR tube and check the functionality.
  3. If everything is okay, then install the EGR tube again.
  4. Remove the engine cover.
  5. Discharge your capacitors and remove the cylinders.
  6. Now replace them with the new ones and install the engine cover.

5.7 Hemi MDS solenoid failure symptoms

Here are some common symptoms of 5.7 Hemi MDS solenoid failure as follows:

  1. DMS Problem
  2. Lifter Problem
  3. Dropped Valve Seat
  4. Ticking Noise
  5. MDS Turning On and off repeatedly.
  6. Vibration
  7. Obnoxious Sound.

Cylinder deactivation solenoid symptoms

Cylinder deactivation solenoid symptoms are as follows:

  • Poor engine performance
  • Misfiring engine
  • Illuminated engine light
  • High fuel consumption
  • Defective ECM
  • Oil passage restriction
  • Damaged and faulty wiring
  • Low engine oil level
  • Loose connector

Bad MDS solenoid symptoms

A bad MDS solenoid will provide a lot of symptoms to make you understand its problem. It may start with the ticking noise which is one of the difficult MDS system issues.

Your lifter can also start showing an exhaust leak which will indicate the internal problem of the engine. DMS problem or dropped valve seat are two of the most common symptoms for the drivers to identify a bad MDS solenoid.

Even your MDS turning on and off may be a symptom of a bad MDS solenoid. Sometimes a bad MDS solenoid can cause vibration and obnoxious sound to the engine. 

5.7 Hemi MDS lifter location

5.7 Hemi MDS lifters are located on the top so that the installation process in the yoke goes easily. They were modified centrally so that they could make room for the high lifter cams used in 5.7 Hemi.

Because of both wider flat sides, they are easily identifiable. But when they fail to accommodate the higher lifters, they often collapse in the MDS model and create issues for the 5.7 Hemi. 

5.7 Hemi MDS solenoid problem solutions

Here we are discussing the solutions of the 5.7 Hemi MDS solenoid problem as follows:

  1. Changing the engine oil and oil filter time-to-time.
  2. Replacing the 5.7 Hemi Cylinder deactivation solenoid. 
  3. Fixing the faulty wires or buying new ones.
  4. Cleaning all the corrosion from the connectors.
  5. Flashing the ECM properly.
  6. Cleaning all the blocked engine oil passages.

5.7 Hemi MDS solenoid delete

Deleting 5.7 Hemi MDS solenoid is never an option. You can only disable it using a tuner. It was built that way so that no one can delete it even they want. People who remove or replace the lifters and camshafts are mostly upgrading the camshaft.

They are usually non-MDS and therefore they can remove them. But 5.7 Hemi MDS solenoid delete is never possible. 

 oil pressure-related problems in 5.7 Hemi.

5.7 Hemi oil pressure at idle 

What is the best synthetic oil for a 5.7 Hemi?5.7 Hemi Oil Pan Bolt Torque

MDS solenoid sticking

If you ever face a situation where your MDS solenoid gets stick to any part of the engine, then you should not get worried and follow our guidelines properly to get your MDS solenoid out.

You can use a straight blade screwdriver and delve into it. Stick the screwdriver inside of the MDS solenoid and try to pry upwards.

 It may break some plastic materials inside of the engine but a little spring will come out along with some other pieces probably. You better keep those pieces safely and then set them properly inside of the engine later. But after doing this, your sticking problem will certainly be solved. 

MDS solenoid replacement cost

MDS solenoid replacement cost depends on your preference and budget. If you want a high-quality MDS solenoid, then you need to pay a bit higher amount. On the other hand, if you want to medium or low-quality MDS solenoid, then you will require lesser money.

You will find all the available replacements on e-commerce websites like Amazon and Ali Express. The average price of MDS solenoid on Amazon is $173 and you will find a variety of products available there. So, you can choose according to your budget and preference. 

Frequently Asked Questions

How many MDS solenoids do a 5.7 hemi have?

There are four empty MDS solenoids on a 5.7 Hemi. You can easily see all four MDS solenoid holes on both sides of the camshaft tunnel. During MDS operation all four cylinders will always shut down. 

How do you remove the MDS solenoid from a Hemi valve?

Here are some steps that you need to follow to remove the MDS solenoid from a Hemi valve as follows:

  1. Find the connection point and disconnect the cable of the negative battery.
  2. Remove the intake manifold.
  3. Find wiring harness connectors and remove them from the MDS solenoids. 
  4. Search for hold-down bolts and remove them from the MDS solenoids once you find them.
  5. Finally, remove the MDS solenoids from the Hemi valve. 

Does the 5.7 Hemi have cylinder deactivation?

In the 2006 year series model, all seven released models are equipped with the 5.7L Hemi engine and they also use a cylinder deactivation system. The purpose of this deactivation system is to deactivate the valve lifters.

The cylinder deactivation system also keeps all four-cylinder valves closed without any combustion. When air is properly pumped through the cylinders, then no energy will be lost. 

How do you turn off MDS Hemi?

You need to follow three basic steps to turn off MDS Hemi and they are as follows:

  1. Your transmission will be equipped with an auto-stick feature and you need to use that in the first place. If the transmission is in auto-stick mode, then the MDS is deactivated automatically. 
  2. You can also disable the MDS Hemi by installing a high-performance camshaft in your Hemi engine. 
  3. You can use your tuner from aftermarket to turn off MDS Hemi. 


Learning about the 5.7 Hemi Cylinder Deactivation Solenoid Location can help you with a lot of things. Almost all vehicles face engine and other issues, but that doesn’t mean it is the end of your vehicle.

If you are well-aware of the locations, then you can check the issues yourself and then take them to a mechanic to solve them. But sending it to an expert without knowing the issue can bring a huge loss for you.

Often expert mechanics will say that your vehicle is not worth fixing and ask you to replace it with a new one. But most of the time a cylinder solenoid needs repairing or maintenance.

Therefore, knowledge about 5.7 Hemi Cylinder Deactivation Solenoid Location can be a great help for you if your cylinder deactivation solenoid gets issues. 

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