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Typical EGR Valve Engine Tune-Up 2003
Vehicles with an OBD-II diagnostic capable PCM can monitor the EGR valve for malfunctions and proper exhaust flow. When it detects a malfunction, it will turn the MIL on since it is directly related to an emission problem.
There are a couple of ways to quickly test an EGR valve. One is to simply unplug it, cap off the vacuum line and drive the vehicle. If the problem goes away, you have a problem with the EGR control system.
The other way is to connect a hand vacuum pump to the EGR valve and slowly apply vacuum to it. If the engine rpm slows down and stumble and probably stall when you get to full vacuum.
If there is no change in the engine rpm remove the EGR valve and perform the same test, this time watching the valve to open. If it does, then you have clogged EGR passages.
If the engine has been idling rough, look for heavy carbon deposits around the pin valve. If there are any clean them off with a wire brush. This will only work with an exposed pin EGR valve. If yours is a recessed pin EGR valve, it will have to be replaced.
The Battery
Today's vehicles place a heavy load on the battery. They have a constant drain on them by PCMs with keep-alive memories, radio memories and other such devices with adaptive learning strategies. This makes clean, corrosion free battery terminals very important. Even a slight corrosion film on a top or side post battery terminal can cause a memory to be lost or cause a charging problem.
On a top post battery, remove the terminal and with a wire brush clean the post until it is just shiny and scratchy. Do the same to the battery terminal on the cable end. If the battery post is too far gone, you will need to replace the battery. If the battery cable terminal is too far gone, you can get a replacement battery cable. Yeah, I know they sell replacement terminals, but I only use them as a last resort. Most times they only allow a corrosion problem to return with a vengeance.
On a side post battery wire brush the face of the battery and cable terminal until it is shiny, scratchy clean. When you reattach the terminals make sure it goes on straight and not cross-threaded. Also don't tighten the terminals too tight. You will rip the connections inside the battery apart. There is a reason why that big terminal has such a small hex head on it.
Then wash the battery and keep it clean. Dirt and oil on the top of the battery will cause a parasitic drain that reduces battery life. When everything is clean and tight, a coating of white lithium grease or spray battery terminal protector will keep the terminals from corroding again. If you have a can of spray paint in the garage, use that. The idea is to keep air from getting to the lead. Don't forget to get the underside of the terminal, between the terminal and the battery.
Where To Get Service Information
When you perform any diagnostics it's not much good to get, say, a voltage reading if you don't know what the correct reading is supposed to be. And testing has become an exact science. Diagnostics have to be performed in a certain order or the test results you get could very well be meaningless. So you need to find the latest factory diagnostic sequences and specifications.
Some vehicle manufacturers have web sites with this service information, and you'll be able to access the data on a daily, weekly, monthly or annual basis.
But, as my Grandfather used to say, there is no such thing as a free lunch. There is a charge for this information. At present, Ford Motor's information is available for $9.95 for a 72-hour access period at Motorcraft Technical Resources.
GM offers a similar program at their ACDelco Tech Connect web site. Or you can get a low-cost subscription from Alldata DIY. In addition; AutoZone offers free scan tool connections and readouts at its stores when you have a lit MIL.
A great place to get service information for free is your local Public Library. The Reference Section has all the different service and repair manuals from Chilton, Haynes, Motor and many others. If they don't have the one you need, ask at the Reference Desk and they will get it from the main branch.
Many public libraries subscribe to online services like Alldata and Mitchell On Demand and can print out the information you need.
Typical EGR Valve Engine Tune-Up 2003
Vehicles with an OBD-II diagnostic capable PCM can monitor the EGR valve for malfunctions and proper exhaust flow. When it detects a malfunction, it will turn the MIL on since it is directly related to an emission problem.
There are a couple of ways to quickly test an EGR valve. One is to simply unplug it, cap off the vacuum line and drive the vehicle. If the problem goes away, you have a problem with the EGR control system.
The other way is to connect a hand vacuum pump to the EGR valve and slowly apply vacuum to it. If the engine rpm slows down and stumble and probably stall when you get to full vacuum.
If there is no change in the engine rpm remove the EGR valve and perform the same test, this time watching the valve to open. If it does, then you have clogged EGR passages.
If the engine has been idling rough, look for heavy carbon deposits around the pin valve. If there are any clean them off with a wire brush. This will only work with an exposed pin EGR valve. If yours is a recessed pin EGR valve, it will have to be replaced.
The Battery
Today's vehicles place a heavy load on the battery. They have a constant drain on them by PCMs with keep-alive memories, radio memories and other such devices with adaptive learning strategies. This makes clean, corrosion free battery terminals very important. Even a slight corrosion film on a top or side post battery terminal can cause a memory to be lost or cause a charging problem.
On a top post battery, remove the terminal and with a wire brush clean the post until it is just shiny and scratchy. Do the same to the battery terminal on the cable end. If the battery post is too far gone, you will need to replace the battery. If the battery cable terminal is too far gone, you can get a replacement battery cable. Yeah, I know they sell replacement terminals, but I only use them as a last resort. Most times they only allow a corrosion problem to return with a vengeance.
On a side post battery wire brush the face of the battery and cable terminal until it is shiny, scratchy clean. When you reattach the terminals make sure it goes on straight and not cross-threaded. Also don't tighten the terminals too tight. You will rip the connections inside the battery apart. There is a reason why that big terminal has such a small hex head on it.
Then wash the battery and keep it clean. Dirt and oil on the top of the battery will cause a parasitic drain that reduces battery life. When everything is clean and tight, a coating of white lithium grease or spray battery terminal protector will keep the terminals from corroding again. If you have a can of spray paint in the garage, use that. The idea is to keep air from getting to the lead. Don't forget to get the underside of the terminal, between the terminal and the battery.
Where To Get Service Information
When you perform any diagnostics it's not much good to get, say, a voltage reading if you don't know what the correct reading is supposed to be. And testing has become an exact science. Diagnostics have to be performed in a certain order or the test results you get could very well be meaningless. So you need to find the latest factory diagnostic sequences and specifications.
Some vehicle manufacturers have web sites with this service information, and you'll be able to access the data on a daily, weekly, monthly or annual basis.
But, as my Grandfather used to say, there is no such thing as a free lunch. There is a charge for this information. At present, Ford Motor's information is available for $9.95 for a 72-hour access period at Motorcraft Technical Resources.
GM offers a similar program at their ACDelco Tech Connect web site. Or you can get a low-cost subscription from Alldata DIY. In addition; AutoZone offers free scan tool connections and readouts at its stores when you have a lit MIL.
A great place to get service information for free is your local Public Library. The Reference Section has all the different service and repair manuals from Chilton, Haynes, Motor and many others. If they don't have the one you need, ask at the Reference Desk and they will get it from the main branch.
Many public libraries subscribe to online services like Alldata and Mitchell On Demand and can print out the information you need.