Service Engine soon Light question
Question:
ONLY IF THE TRUCK IS PRE-OBD-II. The OBD-II standard for onboard diagnostics threw out the ability of the shadetree mechanic to pull codes without any form of a scan tool, this being the "paperclip method". When you jumper the correct 2 contacts together on the ALDL under the dash (keep in mind this is an OBD-I vehicle I’m talking about) the SES light blinks the codes out. I think GM’s standard for the connector was that the top row, 2 connectors on the right end were the ones to connect to get the codes… – Hide quoted text — Show quoted text – > Hey Mike, > Can you jumper out to points and have the read out in flashing lights or > beeps of the horn??? To get the failure mode codes??? > Marc > OBDII tools are more expensive than the old ‘paperclip’ tools, but there > are > some that are no more than a trip to the dealer. > Local parts stores should have a low-end handheld tool that will give you > very basic info. Check out www.autotap.com for a PC based tool that gives > a > lot more info (but requires a PC to be connected). > You wouldn’t be the first to use the ‘black tape repair’ but I wouldn’t > recommend it, if that light ever starts blinking on and off you’ll want to > know right away! > -mike > > AAGM group, > > Thanks for the ideas! Given the nasty shit in the air ( and probably > the > > gas) here in Las Vegas, I am focusing on the fuel filter and EGR valve > as > a > > culprit!…… > > Also, who has ODB II diagnostics tools, are there alternative read-out > > methods, etc…. > > I have a small piece of my black electric tape ready should it be > needed. > > PS the light went out today, all day, and has been out for 30 days > prior. > > Yesterday was a low on gas in the tank day, and hot as hell… Today was > > filler-up day…. not quiet so hot… > > Marc > > > actually, that 9 times out of 10 for the egr valve may be in your > opinion. > > > i had that fail once on my truck, but everytime after that is was the > fuel > > > filter causing the problem…replacing it did the trick. there are > > numerous > > > sensors that will trigger it and i have found over numerous gm > vehicles > > that > > > our family owns that is has rarely been the egr. > > > > 9 times out of 10, when the service engine soon light comes on, it > is > > the > > > > EGR valve. Still, it could be a number of things. It should be > checked > > to > > > > see what is causing it. Oh, By the way, do you put your gas cap on > > tight?? > > > > That will set it off also. > > > > In article > > > > > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine > soon > > > light > > > > > comes on occasionally. What systems trigger the lamp? or is it > just > > > > > telling me that I am nearing 50K miles, a major maintenance > point?? > > > Thanks > > > > > in advance > > > > > marc > > > > — > > > > See ya!!! > > > > Danman
Response:
Hey Mike, Can you jumper out to points and have the read out in flashing lights or beeps of the horn??? To get the failure mode codes??? Marc – Hide quoted text — Show quoted text – > OBDII tools are more expensive than the old ‘paperclip’ tools, but there are > some that are no more than a trip to the dealer. > Local parts stores should have a low-end handheld tool that will give you > very basic info. Check out www.autotap.com for a PC based tool that gives a > lot more info (but requires a PC to be connected). > You wouldn’t be the first to use the ‘black tape repair’ but I wouldn’t > recommend it, if that light ever starts blinking on and off you’ll want to > know right away! > -mike > AAGM group, > Thanks for the ideas! Given the nasty shit in the air ( and probably the > gas) here in Las Vegas, I am focusing on the fuel filter and EGR valve as > a > culprit!…… > Also, who has ODB II diagnostics tools, are there alternative read-out > methods, etc…. > I have a small piece of my black electric tape ready should it be needed. > PS the light went out today, all day, and has been out for 30 days prior. > Yesterday was a low on gas in the tank day, and hot as hell… Today was > filler-up day…. not quiet so hot… > Marc > > actually, that 9 times out of 10 for the egr valve may be in your > opinion. > > i had that fail once on my truck, but everytime after that is was the > fuel > > filter causing the problem…replacing it did the trick. there are > numerous > > sensors that will trigger it and i have found over numerous gm vehicles > that > > our family owns that is has rarely been the egr. > > > 9 times out of 10, when the service engine soon light comes on, it is > the > > > EGR valve. Still, it could be a number of things. It should be checked > to > > > see what is causing it. Oh, By the way, do you put your gas cap on > tight?? > > > That will set it off also. > > > In article
– Hide quoted text — Show quoted text -> > > > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon > > light > > > > comes on occasionally. What systems trigger the lamp? or is it > just > > > > telling me that I am nearing 50K miles, a major maintenance point?? > > Thanks > > > > in advance > > > > marc > > > — > > > See ya!!! > > > Danman
Response:
OBDII tools are more expensive than the old ‘paperclip’ tools, but there are some that are no more than a trip to the dealer. Local parts stores should have a low-end handheld tool that will give you very basic info. Check out www.autotap.com for a PC based tool that gives a lot more info (but requires a PC to be connected). You wouldn’t be the first to use the ‘black tape repair’ but I wouldn’t recommend it, if that light ever starts blinking on and off you’ll want to know right away! -mike
– Hide quoted text — Show quoted text -> AAGM group, > Thanks for the ideas! Given the nasty shit in the air ( and probably the > gas) here in Las Vegas, I am focusing on the fuel filter and EGR valve as a > culprit!…… > Also, who has ODB II diagnostics tools, are there alternative read-out > methods, etc…. > I have a small piece of my black electric tape ready should it be needed. > PS the light went out today, all day, and has been out for 30 days prior. > Yesterday was a low on gas in the tank day, and hot as hell… Today was > filler-up day…. not quiet so hot… > Marc > actually, that 9 times out of 10 for the egr valve may be in your opinion. > i had that fail once on my truck, but everytime after that is was the fuel > filter causing the problem…replacing it did the trick. there are > numerous > sensors that will trigger it and i have found over numerous gm vehicles > that > our family owns that is has rarely been the egr. > > 9 times out of 10, when the service engine soon light comes on, it is > the > > EGR valve. Still, it could be a number of things. It should be checked > to > > see what is causing it. Oh, By the way, do you put your gas cap on > tight?? > > That will set it off also. > > > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon > light > > > comes on occasionally. What systems trigger the lamp? or is it just > > > telling me that I am nearing 50K miles, a major maintenance point?? > Thanks > > > in advance > > > marc > > — > > See ya!!! > > Danman
Response:
AAGM group, Thanks for the ideas! Given the nasty shit in the air ( and probably the gas) here in Las Vegas, I am focusing on the fuel filter and EGR valve as a culprit!…… Also, who has ODB II diagnostics tools, are there alternative read-out methods, etc…. I have a small piece of my black electric tape ready should it be needed. PS the light went out today, all day, and has been out for 30 days prior. Yesterday was a low on gas in the tank day, and hot as hell… Today was filler-up day…. not quiet so hot… Marc
– Hide quoted text — Show quoted text -> actually, that 9 times out of 10 for the egr valve may be in your opinion. > i had that fail once on my truck, but everytime after that is was the fuel > filter causing the problem…replacing it did the trick. there are numerous > sensors that will trigger it and i have found over numerous gm vehicles that > our family owns that is has rarely been the egr. > 9 times out of 10, when the service engine soon light comes on, it is the > EGR valve. Still, it could be a number of things. It should be checked to > see what is causing it. Oh, By the way, do you put your gas cap on tight?? > That will set it off also. > > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon > light > > comes on occasionally. What systems trigger the lamp? or is it just > > telling me that I am nearing 50K miles, a major maintenance point?? > Thanks > > in advance > > marc > — > See ya!!! > Danman
Response:
Robert, Manual is my friend. He’s good with cars but we do not keep him confined to the glove box! Thanks, Marc
– Hide quoted text — Show quoted text -> It indicates some sort of engine control or emissions control problem, such > as a sensor problem, engine misfire, fuel evaporative system leakage, etc. > You need an OBD II capable scan tool to read the diagnostic code to see > exactly what it is. > BTW, that thing in the glove box called a manual.. > — > Robert Hancock Saskatoon, SK, Canada > Home Page: http://members.home.net/hancockr > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon light > comes on occasionally. What systems trigger the lamp? or is it just > telling me that I am nearing 50K miles, a major maintenance point?? Thanks > in advance > marc
Response:
9 times out of 10, when the service engine soon light comes on, it is the EGR valve. Still, it could be a number of things. It should be checked to see what is causing it. Oh, By the way, do you put your gas cap on tight?? That will set it off also. > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon light > comes on occasionally. What systems trigger the lamp? or is it just > telling me that I am nearing 50K miles, a major maintenance point?? Thanks > in advance > marc
– See ya!!! Danman
Response:
actually, that 9 times out of 10 for the egr valve may be in your opinion. i had that fail once on my truck, but everytime after that is was the fuel filter causing the problem…replacing it did the trick. there are numerous sensors that will trigger it and i have found over numerous gm vehicles that our family owns that is has rarely been the egr.
– Hide quoted text — Show quoted text -> 9 times out of 10, when the service engine soon light comes on, it is the > EGR valve. Still, it could be a number of things. It should be checked to > see what is causing it. Oh, By the way, do you put your gas cap on tight?? > That will set it off also. > I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon light > comes on occasionally. What systems trigger the lamp? or is it just > telling me that I am nearing 50K miles, a major maintenance point?? Thanks > in advance > marc > — > See ya!!! > Danman
Response:
It indicates some sort of engine control or emissions control problem, such as a sensor problem, engine misfire, fuel evaporative system leakage, etc. You need an OBD II capable scan tool to read the diagnostic code to see exactly what it is. BTW, that thing in the glove box called a manual.. — Robert Hancock Saskatoon, SK, Canada Home Page: http://members.home.net/hancockr
– Hide quoted text — Show quoted text -> I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon light > comes on occasionally. What systems trigger the lamp? or is it just > telling me that I am nearing 50K miles, a major maintenance point?? Thanks > in advance > marc
Response:
I had a similar problem with my 97 sonoma 4.3l…light would come on occasionally, i could almost predict when it would come on. It looked to be fuel related, but rather than fork out $80+ to the dealer to diagnose it on the computer i started replacing filters and doing other maintenance that i do not usually do. Replaced the fuel filter and problems went away. I hear that GM’s like to have fuel filters changed dang near as often as oil filters. fuel filter that i replaced stank of something other than clean fuel. truck only had 52k’s on it.
– Hide quoted text — Show quoted text -> There are a number of sensors on the engine, transmission, exhaust, and > intake systems that are linked to the Engine Control Module for > monitoring. If one of these sensors indicates an abnormal condition then > the SES lamp is lit. The only way to tell what is going on is to hook the > On Board diagnostics to a code reader and decode the output using the > service manuals. > My most recent experience with this little gem of intelligence was with > something called a cam position sensor. The SES lite would come on and > stay on for a number of days and then not light for a few days and then > repeat its cycle. The only noticable change was slightly better gas > mileage 
. I took the truck (95 Chevy) in for 100K service they fixed > the "problem" 
now I’m back to poor mileage, but the lite is not on. > I guess this proves that if it aint really broke don’t fix it. Take the > damn bulb out if it bothers you.
Response:
I have a Chevy Tahoe 96, with 45.9 K miles. The service engine soon light comes on occasionally. What systems trigger the lamp? or is it just telling me that I am nearing 50K miles, a major maintenance point?? Thanks in advance marc
Response:
There are a number of sensors on the engine, transmission, exhaust, and intake systems that are linked to the Engine Control Module for monitoring. If one of these sensors indicates an abnormal condition then the SES lamp is lit. The only way to tell what is going on is to hook the On Board diagnostics to a code reader and decode the output using the service manuals. My most recent experience with this little gem of intelligence was with something called a cam position sensor. The SES lite would come on and stay on for a number of days and then not light for a few days and then repeat its cycle. The only noticable change was slightly better gas mileage . I took the truck (95 Chevy) in for 100K service they fixed the "problem" now I’m back to poor mileage, but the lite is not on. I guess this proves that if it aint really broke don’t fix it. Take the damn bulb out if it bothers you.
