Author Topic: EGR Valve  (Read 9494 times)

Offline dbolen3

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EGR Valve
« on: January 27, 2017, 11:40:31 pm »
Well I am fairly new to the site and have not posted much since I travel a lot for my job and do not get the time to spend on my truck like a lot of y'all do, but I really enjoy all of the posts and have learned a lot in a short amount of time.

I am Dave and I have a 1987 R10 Silverado long bed with a 305 TBI and was wondering if the EGR valve can cause a service engine light that comes and goes. It runs good with no problems and does not even run bad when the light comes on, just trying to figure out what is causing the problem.


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Offline Captain Swampy

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Re: EGR Valve
« Reply #1 on: January 28, 2017, 12:24:10 am »
I suppose it could. Best to check the codes and see what it is. A paperclip between the correct terminals will flash the codes on your service engine light. I don't remember which terminals, maybe look in the tech section.
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Offline Tazman

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Re: EGR Valve
« Reply #2 on: January 28, 2017, 07:40:02 am »
Oreilly's has the OBGD1 scan reader for these trucks for about 19 bucks.
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Offline Irish_Alley

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Re: EGR Valve
« Reply #3 on: January 28, 2017, 08:26:02 am »
bad part about obd1 is it might have the code on file if the light isnt on. egr is only active under certain conditions my 95 4.3 has the obd1 and if im cruising with light throttle and at a constant speed my cel will come on but if i press the gas it will go off a few seconds later
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Offline VileZambonie

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Re: EGR Valve
« Reply #4 on: January 28, 2017, 08:48:28 am »
Terminal A+B jumpered in the DLC with key on engine off will reveal your codes.

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Offline dbolen3

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Re: EGR Valve
« Reply #5 on: January 28, 2017, 09:38:41 pm »
Thanks for all the suggestions and will check the codes tomorrow.


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Offline dbolen3

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Re: EGR Valve
« Reply #6 on: March 01, 2017, 07:39:24 pm »
Thanks for all the suggestions and will check the codes tomorrow.


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Well I found my problem, it was the a loose hose from the EGR valve to the EGR switch. Now after I fixed it the engine is not running as good as it was, does that mean that my EGR valve is going bad or the switch? If anyone has had this problem I would appreciate some help so I do not change any parts that is not needed.


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Offline VileZambonie

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Re: EGR Valve
« Reply #7 on: March 02, 2017, 08:49:02 am »
If vacuum is present at the EGR valve with the engine running, replace the EGR solenoid.
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Offline dbolen3

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Re: EGR Valve
« Reply #8 on: March 02, 2017, 07:16:40 pm »
If vacuum is present at the EGR valve with the engine running, replace the EGR solenoid.
So what brand would you recommend if I need to replace it? I have read many of your responses and you have a good following of helping all of us out with the problems.


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Offline Dr_Snooz

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Re: EGR Valve
« Reply #9 on: March 02, 2017, 10:05:10 pm »
In the factory service manual, there is a relatively simple flowchart that tests the EGR system. The manual is available on the site somewhere I believe. Maybe someone can help me?
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Offline Captkaos

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Offline Dr_Snooz

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Re: EGR Valve
« Reply #11 on: March 03, 2017, 09:16:55 pm »
Um... you need the Fuel and Emissions one. It's on p. 9-5 of my '89 manual. Not that that's going to help with your '87. LOL
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Offline VileZambonie

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Re: EGR Valve
« Reply #12 on: March 04, 2017, 08:37:50 am »
If vacuum is present at the EGR valve with the engine running, replace the EGR solenoid.
So what brand would you recommend if I need to replace it? I have read many of your responses and you have a good following of helping all of us out with the problems.


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All you need to do is pull the vacuum hose off of the EGR valve. If vacuum is present at idle, the solenoid is stuck open. I am not brand loyal to these types of parts. Get what's readily available to you.
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Offline dbolen3

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Re: EGR Valve
« Reply #13 on: March 06, 2017, 10:18:35 pm »
If vacuum is present at the EGR valve with the engine running, replace the EGR solenoid.
So what brand would you recommend if I need to replace it? I have read many of your responses and you have a good following of helping all of us out with the problems.


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All you need to do is pull the vacuum hose off of the EGR valve. If vacuum is present at idle, the solenoid is stuck open. I am not brand loyal to these types of parts. Get what's readily available to you.
Hey Vile thanks for the help and ended up replacing it with one from Napa. Seems to be running better and actually helped smooth out the engine too.


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Offline VileZambonie

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Re: EGR Valve
« Reply #14 on: March 07, 2017, 05:09:04 pm »
 8) Glad to hear
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