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01-10-06, 06:11 PM
|  | Cadillac Owners Fanatic Cadillac(s): 96 sts | | | | | Re: How To Clean The EGR Valve I just recently bought a 96 sts and the guy had all the receipts from the all the work that had been done to it. He had a mechanic put on a new EGR valve and it costed about $250 (parts and labor).
Glad the previous owner put one in before I bought, saves me some dough.  | 
01-10-06, 08:25 PM
|  | Cadillac Owners Connoisseur Cadillac(s): 94 Eldorado, and a totaled z rated STS | | Join Date: Sep 2004 Location: Hilo, Hawaii Age: 22 | | | Re: How To Clean The EGR Valve Quote: |
Originally Posted by Eldyfig In Krashed's pics, his gasket is still on the valve. | Yes it is but I didn't document that I also changed the gasket afterwards. I changed it because that's actaully half of the gasket on the valve and the other half is still on the engine. The layers of it just split apart. Quote: |
Originally Posted by tkarlstad Great tip, but I see this cleaning tip is specific to the OBD-I Northstar 4.6L V8.
I have a 98 Eldo ETC. I believe that would fall into the OBD-II, correct?
I have similar gas pedal sticking problems and slight RPM movement when the car idles when cold.
Could this same tip be used to clean my EGR valve, or is it different on a 98-Eldo?
Thanks
Tim | Yours is probably about the same, I just wasn't sure if the locations, or bolt patterns were different.
If your gas petal is sticking, you have a totally different problem. My gas petal has never been sticky, but when I tried to keep the gas petal steady to keep a pace up a hill, my car would surge instead of going steady. For me, the surging never happened at idle, but I'm not sure if it's possible or not for the EGR valve to cause suging at idle. Quote: |
Originally Posted by denscor If I was to put the EGR valve in carb cleaner overnight would it be ok? How about doing the same to the throttle body? | Just remember that the objective is to keep the carb cleaner out of the canister. Otherwise it might eat away at the insulation on the windings. | 
02-03-06, 12:54 PM
|  | Cadillac Owners Connoisseur Cadillac(s): 2003 White Diamond DHS | | Join Date: Jan 2005 Location: Dallas, TX | | | Re: How To Clean The EGR Valve I cleaned out the EGR valve. Man--removing it and installing it was a bear.
Although I don't have a steel fuel rail (recall only goes up to 1997), I have the metal bracket atop the EGR valve. I dropped a fastener (nut that fastens the metal plate to the top of the EGR valve) into the engine valley--and lost it.
My carb cleaner was misplaced--so I tried electronics cleaner and to my surprise a slurry of black water came out and the valve was squeaky clean. Nice surprise. The valve did not seem to be getting stuck before or after, but the shaft did have a lot of carbon deposits on it, which I successfully removed with the electronics cleaner and a small brush.
I scraped the old gasket off with a razor blade, and it was a bear all over again to put the EGR valve in, with that thick bracket in the way. | 
03-04-06, 06:08 PM
| | Cadillac Owners Member Cadillac(s): deville 99 | | | | | Re: How To Clean The EGR Valve Man, I had alot of fun with my dad's 99 deville at 97k miles today. Symptoms: stall at low speed, misfiire P300 code, and surging on moderate/heavy acceleration. Heavy acceleration to 4000rpm would cause it to stall. No other code than P300. And my father babys the N*
Cleaned out the throttle body, and cleaned out the EGR valve. Both were filled with crap. On the 99 deville, there's no spark wire cover, but there's a different kind of headache, a bracket that attaches between the fuel lines and one of the EGR screws. Take the nut off, then gently push the fuel line away from the EGR to clear the bracket off that screw, then proceed to remove that screw.
After cleaning both TB and EGR out, topped out the gas tank (11 gals) of Shell 93, I went to a backroad and floored it. Problem solved... now I need to do a couple more WOT's before giving it back to the old man. | 
03-07-06, 10:45 PM
| | Cadillac Owners Member | | | | | Re: How To Clean The EGR Valve My EGR valve has been causing a rough idle and stalling lately. I recently took it out, cleaned it with carborator cleaner and replaced it and now the vehicle won't turn over. It just keeps cranking. My question to Krashed989 or anyone else was: could this mean i messed up the EGR valve while cleaning it? I sprayed the carb-cleaner inside the two holes and put a paper towel in there to wipe out some of the carbon build-up... I didn't get any cleaner on the black electrical cylinder I don't think... Before I tried to clean out the EGR valve, the vehicle started and ran, though rough and with some stalling, but after the cleaning, won't start. | 
03-08-06, 12:58 PM
| | Cadillac Owners Member Cadillac(s): White Diamond '03 DHS | | Join Date: Jun 2004 Location: Woodstock Ill. Age: 61 | | | Re: How To Clean The EGR Valve Did you check it before reinstalling it? Did the pintle valve move freely without sticking (opened or closed)? Did you pull any electrical connections and forget to plug them back in? | 
03-08-06, 01:23 PM
|  | Cadillac Owners Connoisseur Cadillac(s): 2003 White Diamond DHS | | Join Date: Jan 2005 Location: Dallas, TX | | | Re: How To Clean The EGR Valve I cleaned mine with electronic contact cleaner, and a toothbrush. The electronics contact cleaner was extra insurance in case it managed to get inside the windings.
The thing is I still got the code a couple of times after putting it back together.
I performed the "carbon cleaning" via the intake vacuum with GM Top Engine Cleaner aerosol, then raising RPMs to 2000 and turning the car off when the smoke begins to come out.
A few WOTs later, no more EGR code. I think my pinging with cheap gas could have possibly been related to the EGR. | 
03-09-06, 07:53 AM
|  | Cadillac Owners Enthusiast Cadillac(s): 1997 Cadillac Deville | | Join Date: Jan 2004 Location: New York (too cold for people Age: 27 | | | Re: How To Clean The EGR Valve Would it be unwise to take some Seafoam or GM TEC and put a bit into the intake of the EGR while the car is running in order to clean out the hoses and the whole system? And if it is unwise, is it only unwise because it would damage the valve and nothing else? If so, I think it'd be a good idea to do before changing one (which I think I am about to do...). | 
03-09-06, 12:15 PM
| | Cadillac Owners Member Cadillac(s): White Diamond '03 DHS | | Join Date: Jun 2004 Location: Woodstock Ill. Age: 61 | | | Re: How To Clean The EGR Valve How are you going to do that? Where are you going to put it? Besides that, there is no EGR flow at idle. Just pull it and clean it the conventional way if you need to. | 
03-09-06, 04:36 PM
|  | Cadillac Owners Enthusiast Cadillac(s): 1997 Cadillac Deville | | Join Date: Jan 2004 Location: New York (too cold for people Age: 27 | | | Re: How To Clean The EGR Valve Well was thinking of holding the throttle lever open a wee bit...unless it has to be in drive, wasn't sure. I saw a vacuum line going to it...but calling up the diagram of the valve in my head, that might be bad for it and cause it to stop working, you're right. Might just put it in the return line with it off though. | 
03-09-06, 04:43 PM
|  | Cadillac Owners Connoisseur Cadillac(s): 2003 White Diamond DHS | | Join Date: Jan 2005 Location: Dallas, TX | | | Re: How To Clean The EGR Valve Quote: |
Originally Posted by Tailfin Well was thinking of holding the throttle lever open a wee bit...unless it has to be in drive, wasn't sure. I saw a vacuum line going to it...but calling up the diagram of the valve in my head, that might be bad for it and cause it to stop working, you're right. Might just put it in the return line with it off though. |
Hey wait a minute. Are you talking Northstar? Different beast altogether. Pre Northstar you have to clean out the "mouse holes" inside the throttle body with an old wire hangar. Your proposed method is more orthodox, in that case. Do a search under the correct engine forum. There are plenty of posts on how to tackle the EGR code on a pre-Northstar. | 
03-09-06, 09:43 PM
| | Cadillac Owners Member Cadillac(s): White Diamond '03 DHS | | Join Date: Jun 2004 Location: Woodstock Ill. Age: 61 | | | Re: How To Clean The EGR Valve Wait a minute. "Mouse holes" are on '93/'94 Northstars. He has a 4.5. Mtflight, I believe you are thinking of the EGR "tubes" in the 4.9 tb bore.
That vacuum hose tailfin is discribing goes to the vacuum side of the EGR diaphram (no carbon there). Besides that, the pre Northstar EGRs rarely need cleaning. | 
03-09-06, 10:19 PM
|  | Cadillac Owners Connoisseur Cadillac(s): 2003 White Diamond DHS | | Join Date: Jan 2005 Location: Dallas, TX | | | Re: How To Clean The EGR Valve Quote: |
Originally Posted by Ranger Wait a minute. "Mouse holes" are on '93/'94 Northstars. He has a 4.5. Mtflight, I believe you are thinking of the EGR "tubes" in the 4.9 tb bore.
That vacuum hose tailfin is discribing goes to the vacuum side of the EGR diaphram (no carbon there). Besides that, the pre Northstar EGRs rarely need cleaning. |
Ahhh! I stand corrected.  | 
03-10-06, 07:56 AM
|  | Cadillac Owners Enthusiast Cadillac(s): 1997 Cadillac Deville | | Join Date: Jan 2004 Location: New York (too cold for people Age: 27 | | | Re: How To Clean The EGR Valve Yeah in retrothought, this doesn't seem like a bright idea. So I'm just going to crawl up the exhaust and...ok no...  | 
05-06-06, 06:38 PM
| | Cadillac Owners Member | | | | | Re: How To Clean The EGR Valve I Am Reading Pcm;po171&po174 On The On Board Computer.my Problem Is Rough Idle Or Surging During Idle.what Does The Codes Mean.i Cleaned The Egr Valve But Only Used Carb Cleaner Around The Opening Of The Valve.how Far Do I Go?should I Push The Spring Loaded Valve Al The Way In?i Have A 2001 Deville. | | Cadillac Discussion Tools | | |
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