"Service Engine Soon" Light
Thread Starter
Race Director
Joined: Dec 2005
Posts: 10,702
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From: Professional just means you get paid
"Service Engine Soon" Light
Broad question, but here ya go.
2 hour drive tonight. Averaging 70 ish mph. About 30 minutes in the light comes on. All temps and gauges are within normal ranges.
Fill the gas tank, finish drive at around 60 mph, light is off and stays off.
In my '99 Jimmy, the two times I've had that prompt, it's been the EGR valve. Not necessarily relevant, but it's my only point of reference.
Any ideas? Is there a common trigger, either serious or no so serious
that may trigger this?
86, auto, 36k.
Thanks.
2 hour drive tonight. Averaging 70 ish mph. About 30 minutes in the light comes on. All temps and gauges are within normal ranges.
Fill the gas tank, finish drive at around 60 mph, light is off and stays off.
In my '99 Jimmy, the two times I've had that prompt, it's been the EGR valve. Not necessarily relevant, but it's my only point of reference.
Any ideas? Is there a common trigger, either serious or no so serious
that may trigger this?
86, auto, 36k.
Thanks.
CF Community Team
Joined: Nov 2005
Posts: 5,252
Likes: 2,892
From: Charlotte N.C.
My 92 is the same, I have to be 70+ for 10-12 miles and it comes on. Other than the light, and a EGR code, theres no other symptoms. I did the test tree in the manual and it says the EGR valve but I havn't swapped it out yet because I'm lazy. I have other things I need to do that are ahead of this. If you get it fixed let us know what you did.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Why dont you pull the code and find out before asking so that we're not guessing?
Its going to be EGR though.
Its going to be EGR though.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 10,702
Likes: 0
From: Professional just means you get paid
I'll get at the code, just got to my hotel and thought I'd throw it out there. Like I said, broad question. I can check tomorrow night or the next day.
Race Director
Joined: Aug 2003
Posts: 13,421
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From: Lake Mary Florida
Probably a 32... yeah the EGR DTC doesn't set until the vehicle is above 50 mph. Could be the ECR Valve, control module or vacuum harness. Isn't that expensive to just replace all three parts.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 10,702
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From: Professional just means you get paid
"EGR Valves have been around for a long time. Way back in 1972 GM used them in an attempt to reduce emissions of oxides of nitrogen (NOx) which were a major cause of air pollution, mainly photochemical smog, that kind of smog which is formed when strong sunlight shines down on the exhaust gasses we puke out of our tailpipes by the billions of cubic feet a day."
http://www.misterfixit.com/egrvalve.htm
http://www.misterfixit.com/egrvalve.htm
Pro
Joined: Aug 2005
Posts: 630
Likes: 2
From: BEMIDJI MN
Originally Posted by Yakko
Broad question, but here ya go.
2 hour drive tonight. Averaging 70 ish mph. About 30 minutes in the light comes on. All temps and gauges are within normal ranges.
Fill the gas tank, finish drive at around 60 mph, light is off and stays off.
In my '99 Jimmy, the two times I've had that prompt, it's been the EGR valve. Not necessarily relevant, but it's my only point of reference.
Any ideas? Is there a common trigger, either serious or no so serious
that may trigger this?
86, auto, 36k.
Thanks.
2 hour drive tonight. Averaging 70 ish mph. About 30 minutes in the light comes on. All temps and gauges are within normal ranges.
Fill the gas tank, finish drive at around 60 mph, light is off and stays off.
In my '99 Jimmy, the two times I've had that prompt, it's been the EGR valve. Not necessarily relevant, but it's my only point of reference.
Any ideas? Is there a common trigger, either serious or no so serious
that may trigger this?
86, auto, 36k.
Thanks.
I read somewhere that this can trigger a SES light.
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Melting Slicks
Joined: Mar 2003
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From: Oklahoma City Oklahoma
My knock sensor kept causing my SES light to come on, but what drove me crazy was the stinkin light would never stay on long enough to set a hard code. After six very frustrating months, the thing finally went out, and set the code. 
Team Owner
Joined: Sep 2001
Posts: 62,160
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Originally Posted by Shawn_65
Whats the EGR valve do, I think I have the same problem. Only happens once a month at the most.
Team Owner
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Originally Posted by vader86
Why dont you pull the code and find out before asking so that we're not guessing?
Its going to be EGR though.
Its going to be EGR though.
My 86 has exhibited this same behaviour.
Turned out to be the EGR switch. Its a little gizmo threaded into the EGR tube next to the distributor with a single wire out the top.
Dont remember the code.
Drifting
Joined: Nov 2000
Posts: 1,428
Likes: 1
From: Jacksonville FL
Originally Posted by Billy Stargazer
You may want to check to see that your fuel cap is installed correctly.
I read somewhere that this can trigger a SES light.
I read somewhere that this can trigger a SES light.
Drifting
Joined: May 1999
Posts: 1,478
Likes: 3
From: Sacramento, CA Money can't buy happiness - but it's more comfortable to cry in a Corvette than a Yugo.
Originally Posted by JrRifleCoach
My 86 has exhibited this same behaviour.
Turned out to be the EGR switch. Its a little gizmo threaded into the EGR tube next to the distributor with a single wire out the top.
Dont remember the code.
Turned out to be the EGR switch. Its a little gizmo threaded into the EGR tube next to the distributor with a single wire out the top.
Dont remember the code.