General Tech Help Good at troubleshooting? Have a non specific issue? Discuss general tech topics here.

What does an EGR Valve actually do?

 
Thread Tools
 
Search this Thread
 
  #1  
Old 10-31-2006, 05:23 PM
USMaverick101's Avatar
Thread Starter
Join Date: Sep 2006
Location:
Posts: 130
USMaverick101 is an unknown quantity at this point
Default What does an EGR Valve actually do?

Whats it stand for and what specifically does it exactly do?
 
  #2  
Old 10-31-2006, 05:41 PM
lastcoupe's Avatar
Super Member
Join Date: Jul 2006
Location:
Posts: 1,202
lastcoupe is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

Exhaust Gas Recirculation valve......It reintroduces exhaust gases back into the combustion chamber for lower emissions...basically.
 
  #3  
Old 10-31-2006, 06:18 PM
swartlkk's Avatar
Administrator
Join Date: May 2005
Location: Waterloo, NY
Posts: 41,137
swartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond repute
Default RE: What does an EGR Valve actually do?

^^^Yup, it basically works by lowering the temps in the combustion chamber to prohibit the formation of NOx.
 
  #4  
Old 10-31-2006, 06:48 PM
Join Date: Jul 2006
Location:
Posts: 137
magnum434 is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

Where are they located? How much are they? If they aren't very expensive I might just replace mine or...someting....
 
  #5  
Old 10-31-2006, 06:48 PM
USMaverick101's Avatar
Thread Starter
Join Date: Sep 2006
Location:
Posts: 130
USMaverick101 is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

Ah i see,

How does it effect the performance off the car if it gets stuck? Can it prevent it from starting? And can it spontaneously just fail and cause the car to stall out?
 
  #6  
Old 10-31-2006, 07:40 PM
swartlkk's Avatar
Administrator
Join Date: May 2005
Location: Waterloo, NY
Posts: 41,137
swartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond reputeswartlkk has a reputation beyond repute
Default RE: What does an EGR Valve actually do?

If an EGR valve is stuck open, then yes, it can cause degradation of performance as well as stalling at idle. Many times, this is caused by chunks of carbon getting stuck in the valve holding it open. This is rarely enough to cause real big problems, but it does act as a vacuum leak when it is stuck open, except it isn't fresh air capable of supporting combustion, it is spent exhaust gases.

On the SCFI motors, the EGR valve is located on the front of the engine above the water pump. I believe it is in the same general location on the older CPI motor as well.
 
  #7  
Old 10-31-2006, 08:02 PM
USMaverick101's Avatar
Thread Starter
Join Date: Sep 2006
Location:
Posts: 130
USMaverick101 is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

Yeh i have the CPI motor. Last saturday I was driving and the car just shut off on me, I had it pulled by mr brothers truck back to my house, I thought it was the fuel pump. I looked at the fuse (ECM B) and it was fine. I then thought i needed a new fuel pump. I finally dound the relay, and saw the connecter was all burnt up and melted a little. I think the relay is still ok, but the connection is bad. I bypassed the power(orange wire) to the fuel pump (grey wire), and i tried starting it. Still no cigar. I checked the distributor for spark, OK there. I'm gettign spark. I tried using starting fluid, but it wouldnt start. I then pulled out the plugs and found them to be all wet and coated in black. I cleaned them with a torch and put them back in. Still no start. I checked the shraeder valve and i see im getting fuel there. If the pump is bad, i dont want to change it till i'm 100% sure thats the problem. Even if the pump is bad, won't it still start up with a shot of starting fluid? I've been trying all day and everyday for the past 3 days and im so frustrated. I feel lost without driving my truck at least once a day. [X(]
Anyone got any further suggestions or ideas?
 
  #8  
Old 10-31-2006, 08:13 PM
lastcoupe's Avatar
Super Member
Join Date: Jul 2006
Location:
Posts: 1,202
lastcoupe is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

It sounds like you need to replace those plugs...if they are fuel fouled it may not start at all even after cleaning them off. Typically it will start with a spray of starting fluid or brake cleaner etc... if the pump is bad. take the fuel cap off and stick your ear in it while someone turns the ign. on...you should be able to hear the pump for a few seconds...It really sounds to me like you have an ignition system problem...probably secondary (plugs/wires/cap/coil/rotor). But you could have injector problems if your plugs are fuel-fouling.
 
  #9  
Old 10-31-2006, 09:42 PM
USMaverick101's Avatar
Thread Starter
Join Date: Sep 2006
Location:
Posts: 130
USMaverick101 is an unknown quantity at this point
Default RE: What does an EGR Valve actually do?

Well heres the thing with the plugs. I bought new ones from NAPA, i told them to give me the AC Delco plugs i usually put in, the CR 43TS. I get home and i realize they gave me R 42TS. I called the guy from NAPA, and he said if I was just trying to get it started that even putting in the 42TS would get it started, he said that those plugs woudlnt stop it from starting cuz theyre only one number off. I took his word and I put those in anyways, still no luck.
Also, just last month, I replaces the plugs, wires, and cap. Just last week I put in a bottle of techron fuel system cleaner. I flush the engine at every oil change, and add a few addatives that are recommended.
Still not sure what it could be.
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
IndianaBlazerGirl
2nd Generation S-series (1995-2005) Tech
5
09-06-2011 06:22 PM
midnightbluS10
2nd Generation S-series (1995-2005) Tech
0
03-28-2010 10:50 AM
Katmandu
The Lounge
11
09-13-2009 01:39 PM
94blueknight
Headers, Intake, & Exhaust
7
01-29-2008 10:30 AM
rustybeast
General Tech Help
24
11-22-2006 12:19 AM



Quick Reply: What does an EGR Valve actually do?



All times are GMT -5. The time now is 02:33 AM.