Detecting a Leak with the Aid of a Diagnostic OBD2 Scanner


The OBD2 system, especially when used in conjunction with a Diagnostic OBD2 Scanner can help detect initial faults which the human eye will not be capable seeing until the fault becomes more evident. This system is a very sophisticated and intelligent system which prevents most faults from building up unnoticed. A typical example of such is fault code P0456. This fault code when deciphered means Minor Leak detected in Evaporative Emissions System. A detailed explanation and how to decipher a fault code from a reader or scanner which only gives the code can be found on my other previous posts. This minor fault is not only very difficult to trace unless there are obvious signs like damp or wet parts, cracked pipes and loose pipe fittings, to name a few but it takes ages tracing the whole fuel system.

Conventional vehicles without any PCM (Powertrain Control Module) or as known by most Europeans ECU (Electronic - Engine Control Unit) which had everything mechanical and electrical, with no electronic circuits might have been simpler in their own form and were easier at times to work on, but such a fault would surely go unnoticed for ages before the smell of fuel vapor becomes too evident. Even then, if there is no visual indication there will be a long diagnosing mission to try and find where the vapors are escaping from. The method of a smoke machine or color dye is still used today as it was used then but as we can see we only need to check visually, then with a smoke machine around the EVAP system only, not the whole fuel system, starting from either end (fuel tank or carburetor) then moving forwards, till the culprit is found.
Trouble here is that the fault will display on the instrumentation panel on the dash as ‘Check Engine’ or ‘MIL’ (Malfunction Illumination Light). Unless you have access to at least a code reader or better still a diagnostic OBD2 scanner with CAN interface compliancy (for vehicles manufactured after end of 2007 in US – mandatory), then there is no way of telling what the fault is and how bad the situation is. It is always bad to assume that nothing major has occurred if the engine seems to run fine. It is also illegal to drive a vehicle with that warning light on in many parts of the world.

The Evaporative Emission System
The EVAP test is not a test that is constantly being tested like other constant tests. This test is only applied if certain criteria have to be met - otherwise this test will be kept on hold. The main criteria for the test of the EVAP to perform are that the fuel tank has to contain between ¼ - ¾% fuel, it hasn’t been used overnight and vehicle has to be driven for a certain distance. It might not run on certain extreme hot or cold environmental conditions too.

The main reason for the EVAP is to keep any fuel vapor from entering the atmosphere and re-circulates it back to the engine to be burnt off. These tests are conducted from the PCM, monitoring any fuel pressure drop in the system. The EVAP pressure is monitored from the PCM through the Fuel Tank Pressure sensor (FTP) and if there is a drop or difference in pressure it is recorded. Once the tolerance is exceeded it flags up a fault code on the PCM and the ‘MIL’ or ‘Check Engine’ Light is illuminated on the instrument panel. When the system is checked using a diagnostic OBD2 scanner the fault code P0456 emerges on the scanner’s display. With such a fault the engine should keep on running smoothly as engine is not becoming lean on fuel, the EVAP circuit is designed as a close circuit so it doesn’t have any effect on the rest of the program. Possible causes may be a faulty or badly engaged fuel cap, refueling with the engine on (unsafe practice and bad for fuel injection pump), a leaky or worn out hose, loose hose fixtures, miniature purge valve or vent valve leak or tiny leak on EVAP canister.

The best possible way to detect the fault is by breaking down the diagnosis into a small section. Using a diagnostic OBD2 scanner activate the vent solenoid, taking care to seal the rest of the system. Any pressure and any difference are monitored through the FTP and are recorded on the PCM, then entering the scanner. If the pressure reading remains the same, entering the OBD2 scanner screen as constant (same pressure reading) then that test has passed, meaning no leaks. If any pressure difference is recorded it is transferred onto the OBD2 scanner screen and you know there is a vapor or miniature leak somewhere across the EVAP system. If nothing can be seen visually, then the best option is to use a smoke detector. When smoke is seen the leak is uncovered. Never attempt to pressurize the EVAP system with compressed air. This can damage the delicate and accurate the valves in the system.

It is also a good idea after finding and replacing the faulty component to check all hose conditions. If they seem to have any hairline cracks or serious color discoloration, just change them with new ones, using the appropriate fuel hoses and the proper clamping hose devices. Re-check for any leaks with a smoke test. This way there is much less chances that the same code will appear again for a different part, which was overlooked the first time. If you are interested in OBD diagnostic techniques and would like to acquire more tips and information visit Automotive Diagnostic OBD2 Scanner.

Wednesday, September 16, 2009

Why should a Hybrid Engine Conversion be considered?

Engine Hybrid Conversion - Guaranteed Results!

This is simply the way to go unless you already own or are in the process of buying an environmentally friendly hybrid vehicle. All engine types can work and benefit tremendously from this system.

It is a win-win situation as it saves you big money from fuel expenses while also polluting virtually much less poisonous emissions than before the system was installed. It also reduces and eventually cleans up the carbon build-up in the engine.
Another great thing is engine wear is less as it decreases the normal engine operating temperature.
Engine runs smoother and also gains extra power.

This is easily understandable when one considers the fact that hydrogen fuel creates a bigger explosion, which is needed for the engine rotational cycle. This surely will be more effective than traditional fuel. This much stronger power is the key to less fuel and obviously less harmful emissions, commonly found in traditional fuels. Hydrogen emissions are no more than water vapor, so it does not harm the environment in any way - the contrary as a matter of fact!



Tips:


  1. Try installing one now and I guarantee that you'll never look back as the saving alone are enormous. It can be done by a competent D.I.Y.-er or a good qualified mechanic or vehicle technician.

  2. Do not be put off by the many myths about this system from negative people surrounding you. NASA had done some testing more than 20 years ago on a diesel engine and their results were outstanding.

  3. BMW is launching the New 7-series automobile with this kind of system. Surely they are leading by example here and I can assure you they will not launch their best (top) flagship luxury automobile worth thousand s of Dollars if they are not sure the system works fine.

  4. Another global political secret: All countries depend on fuel and they Fully Support (hiddenly) the petroleum industry. They might look environmentally friendly politicians with an ever-green agenda BUT they depend so much on these mega companies that they do not support this system. Australia is currently one of them - there are many more, rest assured!

Benefits:


  1. Your saving on fuel expenses will be massive per year if you use you vehicle very often. That alone and with the current sky-rocketing fuel prices should get you moving in the right direction.

  2. Environmentally friendly and safer than pure hydrogen vehicles as the hydrogen is produced from water on demand only when the engine is running - dangerous storage is eliminated, which is the hazardous problem associated with hydrogen storage in any form. Hydrogen emissions are 100% clean as they are water vapor from vehicle's tailpipe. The only poisonous emissions are the ones from the fuel and these are reduced drastically as fuel consumption is much less.

  3. Do it for the sake of future generations who are not guilty for all our bad deeds to the environment. Remember about the future of your grand children and their futures.

  4. You will not be playing the game of feeding the big boy's mouths - petroleum industry and global politics.

  5. The saying goes "You are what you eat" - you aren't a healthy person if you are driving a toxic vehicle!

 

 

If you think that you should make the final decision for reducing the ozone problem, and most importantly you decide that you should drastically slash your annual fuel expenses (they add up horrendously if you keep all receipts for a year) there are two options available:

  • 1.  Replace your vehicle with a new hybrid or even electric car

OR

  • 2.  Convert your own vehicle to a hybrid one                          

Tip: The conversion is not complicated at all and can be done by competent D.I.Y.-ers if they are inclined enough to read the instructions thoroughly. Any competent mechanic willing to do such an installation, and doesn't consider this a waste of their profitable time can complete the task successfully. You might even convince them that there is a possible market for such a system after all, and they might try and promote it themselves for installation, as they should find it better than major repairs (less time and no oily fingers) adding to their own profits. So there are no excuses whatever - you can have it installed on your vehicle one way or another. The last decision is yours!

If this simple system seems for you Go and Check It Out Here: --->>  http://www.DiagnosticOBD2Scanner.com

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