Check Engine (MIL) lights
11/30/04, 08:04 PM
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I posted this on a different thread buried somewhere, so I thought I'd start a new one... let the flaming begin!! 
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Let me sound in with my two cents worth (probably not worth more than that!!).
I'm a master-certified and advanced L1 auto technician, and have worked both in new car dealerships and independent shops.
1. Blended fuels will NOT turn on a MIL light. Adaptive memory or fuel trim like some manufacturers call it, will adjust the fuel curve to make whatever fuel you are burning run at the proper fuel ratio. (14.7/1)
2. Reving an engine when cold will NOT turn on a check engine light. If it does turn on, the ECU/ECM/PCM has detected something abnormal, probably a cylinder mis-fire. If the engine is running properly and all sensors are within specs, the engine light will not come on just by simply reving the engine.
3. It is possible for a check engine (MIL) light to go off on its own. If the car is driven for 3 'good trips', without the fault returning, the computer will turn the check engine light off. It will though retain the fault and freeze frame data. There are many factors that go into making a 'good trip' which could take all day to explain. Things like cold start to operating temperature, idle time, coast time, cruise times... things like that. Three trips to the corner tap probably won't satisfy a 'good trip'... on the other hand...
4. There usually isn't a problem driving the car with a check engine light on. If the check engine light is flashing, that's different. If it is flashing, the computer sees a fault that could cause a major break-down. An example would be a severe misfire that would cause an extremely lean condition, and lead to catalytic convertor melt-down, and possible engine damage. If your light comes on and starts flashing, park the car ASAP and let Ford tow it in. If the light is on steady, don't panic. Drive the car when you need to, and make an appointment with your Ford dealership.
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car. For example: Chrysler has a TSB for 96-00 minivans for the check engine light coming on with a P0455 fault. (LDP large leak detected). The fix is to replace the cannister vent valve with a new and updated part. I've replaced literally dozens for this complaint. But here's the kicker. If the valve fails under warranty, of course it's fixed at no charge to the customer. But... if the valve fails after your warranty has expired, the customer is responsible for paying for the diagnostics, labor, and the new part. So even though Chrysler knows it has a specific part on their mini-vans that has a high rate of failure, they will not pay for the repairs if your warranty has expired. The manufacturer may allow the dealership to extend the warranty slightly to cover some of these common problems, but that all depends on the specific Manufacturer or dealer involved. The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
I'm not trying to be a know-it-all... just trying to clear up some mis-conceptions.
Maybe I should start a new thread called 'ask the technician'. While I obviously don't know everything (don't tell my wife that), I do know quite a lot and have access to All-Data, Fords computer access, and know technicians working at Ford dealerships. Any questions...?... ask.
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Let me sound in with my two cents worth (probably not worth more than that!!).
I'm a master-certified and advanced L1 auto technician, and have worked both in new car dealerships and independent shops.
1. Blended fuels will NOT turn on a MIL light. Adaptive memory or fuel trim like some manufacturers call it, will adjust the fuel curve to make whatever fuel you are burning run at the proper fuel ratio. (14.7/1)
2. Reving an engine when cold will NOT turn on a check engine light. If it does turn on, the ECU/ECM/PCM has detected something abnormal, probably a cylinder mis-fire. If the engine is running properly and all sensors are within specs, the engine light will not come on just by simply reving the engine.
3. It is possible for a check engine (MIL) light to go off on its own. If the car is driven for 3 'good trips', without the fault returning, the computer will turn the check engine light off. It will though retain the fault and freeze frame data. There are many factors that go into making a 'good trip' which could take all day to explain. Things like cold start to operating temperature, idle time, coast time, cruise times... things like that. Three trips to the corner tap probably won't satisfy a 'good trip'... on the other hand...
4. There usually isn't a problem driving the car with a check engine light on. If the check engine light is flashing, that's different. If it is flashing, the computer sees a fault that could cause a major break-down. An example would be a severe misfire that would cause an extremely lean condition, and lead to catalytic convertor melt-down, and possible engine damage. If your light comes on and starts flashing, park the car ASAP and let Ford tow it in. If the light is on steady, don't panic. Drive the car when you need to, and make an appointment with your Ford dealership.
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car. For example: Chrysler has a TSB for 96-00 minivans for the check engine light coming on with a P0455 fault. (LDP large leak detected). The fix is to replace the cannister vent valve with a new and updated part. I've replaced literally dozens for this complaint. But here's the kicker. If the valve fails under warranty, of course it's fixed at no charge to the customer. But... if the valve fails after your warranty has expired, the customer is responsible for paying for the diagnostics, labor, and the new part. So even though Chrysler knows it has a specific part on their mini-vans that has a high rate of failure, they will not pay for the repairs if your warranty has expired. The manufacturer may allow the dealership to extend the warranty slightly to cover some of these common problems, but that all depends on the specific Manufacturer or dealer involved. The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
I'm not trying to be a know-it-all... just trying to clear up some mis-conceptions.
Maybe I should start a new thread called 'ask the technician'. While I obviously don't know everything (don't tell my wife that), I do know quite a lot and have access to All-Data, Fords computer access, and know technicians working at Ford dealerships. Any questions...?... ask.
11/30/04, 08:18 PM
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Thanks Retro, for a very informative update.
RE: your item #1: Does that mean it is OK to burn "no name" / off brand / convenience store (i.e. the cheapest) gas in the new 2005 Mustang GT, instead of the higher priced brand name gas?
I run the least expensive gas I can find in our 2 6-cylinder Jeep Grand Cherokees (2000 & 1996), and my son's 2000 F-150 4.6L, with no apparent problems to date (done this from 18 months to 6 1/2 years).
But I'm concerned about what to use in the new Stang whenever it arrives. (I do use only Shell or Chevron 93 premium in the 65 fastback 289 4bbl, however.)
Please advise. Thanks.
RE: your item #1: Does that mean it is OK to burn "no name" / off brand / convenience store (i.e. the cheapest) gas in the new 2005 Mustang GT, instead of the higher priced brand name gas?
I run the least expensive gas I can find in our 2 6-cylinder Jeep Grand Cherokees (2000 & 1996), and my son's 2000 F-150 4.6L, with no apparent problems to date (done this from 18 months to 6 1/2 years).
But I'm concerned about what to use in the new Stang whenever it arrives. (I do use only Shell or Chevron 93 premium in the 65 fastback 289 4bbl, however.)
Please advise. Thanks.
11/30/04, 08:18 PM
#3
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Are you aware of a problem on quick de-acceleration and then giving it the gas only to have a major hesitation, like the key was turned off for a half second?(three hesitations rapidly in a row before it ran normal again.
11/30/04, 09:49 PM
#4
Sorry Mike BUT the reason I posted about the blended fuels is that it is stated in my friends pontiac montana owners manual that running blended fuels "Can" turn on the check light if you have changed fuel brands .
But that this problem should clear it's self up after a couple of tank fulls.
I Know a pontiac montana is no mustang but thats why I asked him to check with his owners manual to see what it has to say about this ,for you never know being a new car anything could set the sensor off including the gas cap being loose.
Right now a friend of mine is going through his "mid light crisis" right now one with the montana and another with a freestar just got his fixed.
If you still don't belive me I'll get his owner's manual from the montana and scan that section for you . :angry:
But that this problem should clear it's self up after a couple of tank fulls.
I Know a pontiac montana is no mustang but thats why I asked him to check with his owners manual to see what it has to say about this ,for you never know being a new car anything could set the sensor off including the gas cap being loose.
Right now a friend of mine is going through his "mid light crisis" right now one with the montana and another with a freestar just got his fixed.
If you still don't belive me I'll get his owner's manual from the montana and scan that section for you . :angry:
12/1/04, 06:46 AM
#5
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Originally posted by Retro GT@November 30, 2004, 9:07 PM
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car.
The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car.
The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
My family is the original owner of the the T-bird that had the intake recall. No notice was received from Ford about the recall by any family member.
When the mechanic talked to the Ford rep about the T-Bird, the rep said that a notice was not sent out. But if you called about it, they would fix it. Maybe the rep was incorrect. But since it has happened twice to me and has been explained as an un-notified recall, I have more belief that there is such a thing, than not.
Maybe the rep should have called it a TSB instead of an "un-notified" recall. Sounds like the same thing to me. Tell the technician that some thing is wrong, but don't tell the actual owners. Either way, it is frustrating to break down in the middle of no-where because of a manufacturer defect and not be told about the defect so you can get it fix before it hand.
I am not trying to be a jerk, or am I saying that I am right. I am just explaining what I have experienced.
12/1/04, 07:30 AM
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Originally posted by Kluski+December 1, 2004, 7:49 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Kluski @ December 1, 2004, 7:49 AM)</td></tr><tr><td id='QUOTE'><!--QuoteBegin-Retro GT@November 30, 2004, 9:07 PM
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car.
The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
5. There is no such thing as a 'un-notified recall' as a previous post suggested. I would guess that there was a TSB or technical service bulletin on the problem. These bulletins come from the manufacturer if they have an abnormally high rate of failure with the same car.
The service bulletins are mainly put out to aid the technician and let them know of common problems. If a manufacturer is required to, or even volunteers to put out a recall, by Federal law they must make 3 attempts to contact the current registered owner and notify them of the problem via USPS.
My family is the original owner of the the T-bird that had the intake recall. No notice was received from Ford about the recall by any family member.
When the mechanic talked to the Ford rep about the T-Bird, the rep said that a notice was not sent out. But if you called about it, they would fix it. Maybe the rep was incorrect. But since it has happened twice to me and has been explained as an un-notified recall, I have more belief that there is such a thing, than not.
Maybe the rep should have called it a TSB instead of an "un-notified" recall. Sounds like the same thing to me. Tell the technician that some thing is wrong, but don't tell the actual owners. Either way, it is frustrating to break down in the middle of no-where because of a manufacturer defect and not be told about the defect so you can get it fix before it hand.
I am not trying to be a jerk, or am I saying that I am right. I am just explaining what I have experienced.[/b][/quote]
You're not being a jerk at all. And... you are right. Although not an official recall, sometimes manufacturers will try and conceal a large problem by having it taken care of at the dealer level.
For example: Dodge Neons had a HUGE problem with head-gaskets leaking externally behind cylinder #4. At their peak, we were seeing them daily. Chrysler put out a TSB, and revised the gasket several times until they found one that would last. Never a recall, but Chrysler advised their dealers to extend the warranty on a one by one basis up to 100,000 miles. Some charged a $100-$250 deductible, some did it at no charge, again depending on the dealership.
Was this a recall...no. Should it have been...absolutely. I guess Chrysler just figured that instead of paying to have all the 2.0 and 2.4 headgaskets replaced, they would fix the ones that people complained about.
So I guess technically you could call this an un-notified recall.
The bottom line, from my experience, is to be persistant. Like they always say, the squeaky wheel gets the grease. Many people paid to have their head-gaskets replaced. If they had done a little female *******... it would have been free.
Press your dealer...
... it's amazing what they'll do for you. 
12/1/04, 07:46 AM
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Originally posted by Ripstang@November 30, 2004, 10:52 PM
Sorry Mike BUT the reason I posted about the blended fuels is that it is stated in my friends pontiac montana owners manual that running blended fuels "Can" turn on the check light if you have changed fuel brands .
But that this problem should clear it's self up after a couple of tank fulls.
I Know a pontiac montana is no mustang but thats why I asked him to check with his owners manual to see what it has to say about this ,for you never know being a new car anything could set the sensor off including the gas cap being loose.
Right now a friend of mine is going through his "mid light crisis" right now one with the montana and another with a freestar just got his fixed.
If you still don't belive me I'll get his owner's manual from the montana and scan that section for you . :angry:
Sorry Mike BUT the reason I posted about the blended fuels is that it is stated in my friends pontiac montana owners manual that running blended fuels "Can" turn on the check light if you have changed fuel brands .
But that this problem should clear it's self up after a couple of tank fulls.
I Know a pontiac montana is no mustang but thats why I asked him to check with his owners manual to see what it has to say about this ,for you never know being a new car anything could set the sensor off including the gas cap being loose.
Right now a friend of mine is going through his "mid light crisis" right now one with the montana and another with a freestar just got his fixed.
If you still don't belive me I'll get his owner's manual from the montana and scan that section for you . :angry:
If your vehicle is certified to meet California Emission Standards, indicated on the underhood emission control label, the vehicle is designed to operate on fuels that meet California specifications. If such fuels are not available in states adopting California emissions standards, your vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance may be affected The malfunction indicator lamp (MIL) on your instrument panel may turn ON and/or your vehicle may fail a smog-check test. If this occurs, return to your authorized dealer for diagnosis to determine the cause of failure. In the event that the cause of the condition is the type of fuels used repairs may not be covered by your warranty.
12/1/04, 09:32 AM
#8
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[quote]Originally posted by Retro GT@December 1, 2004, 8:33 AM
[QUOTE=Kluski,December 1, 2004, 7:49 AM]
The bottom line, from my experience, is to be persistant. Like they always say, the squeaky wheel gets the grease. Many people paid to have their head-gaskets replaced. If they had done a little female *******... it would have been free.
Press your dealer... ... it's amazing what they'll do for you.
Oh, I have definetely learned to call immediately after I find something wrong. I don't mind the little things, those I can repair myself. But when there is a big one, I call and bug everyone I can to see if I can get it fixed for free.
[QUOTE=Kluski,December 1, 2004, 7:49 AM]
Originally Posted by Retro GT,November 30, 2004, 9:07 PM
The bottom line, from my experience, is to be persistant. Like they always say, the squeaky wheel gets the grease. Many people paid to have their head-gaskets replaced. If they had done a little female *******... it would have been free.
Press your dealer...
... it's amazing what they'll do for you.
12/1/04, 11:52 AM
#9
Sound good mike,I'll check to see if his vehicle is from California ,but being all the way up in Manitoba Canada it could be something that is just relitive to a Canadian built Car ,seeing that we have extream tempratures up here (mid 90 plus in summer -40 plus in winter with windchill) could play a factor in the sensor light comming on .
I know the blends of Gas change up here per season to deal with the weather .There was a incident a long time ago with Shell were they had shipped the summer gas in winter and most customers cars wouldn't run (happened about 15 years ago).Shell had to pay for the removal of the gas from there tanks and give them a tank full of the proper winter gas.
It was for this reason with my friends with the montana that I posted about the gas for it did state about changing gas brands and blended fuels .But now reading the other link about the sensor's looks like a computer programing error.
I like to thank you for all your input in the forum it's very informative for the members of the mustang source ,didn,t mean to sound off the wrong way but I would not post something unless I thought it was true .If you wish for your information I can still get the owners manual from the montana and scan it .
I know the blends of Gas change up here per season to deal with the weather .There was a incident a long time ago with Shell were they had shipped the summer gas in winter and most customers cars wouldn't run (happened about 15 years ago).Shell had to pay for the removal of the gas from there tanks and give them a tank full of the proper winter gas.
It was for this reason with my friends with the montana that I posted about the gas for it did state about changing gas brands and blended fuels .But now reading the other link about the sensor's looks like a computer programing error.
I like to thank you for all your input in the forum it's very informative for the members of the mustang source ,didn,t mean to sound off the wrong way but I would not post something unless I thought it was true .If you wish for your information I can still get the owners manual from the montana and scan it .
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