# EGR question



## internetautomart (Mar 8, 2004)

is there any way to prevent carbon build up on the EGR valve on these cars?


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## HATEnFATE (Dec 24, 2002)

Remove it.


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## dragontoy22r (Jun 27, 2007)

HATEnFATE said:


> Remove it.


That's not prevention. 
There's a product called SEAFOAM, I use quite often. Buy one can, add half to your crankcase (oil), and 1/4 to 2/3 of a can fed through a primary vacuum hose. Either hose that comes from your PCV valve or your brake booster will work. 
With the engine running, remove one of the two lines I suggested above and tip the can of SEAFOAM slowly into it. Feed it slowly enough at first to get about a 1/4 of the can in, then feed it quickly enough to try to stall the engine out. If it doesn't stall, shut the engine off immediately after adding the amount you wanted. Let it sit for about 15-20 minutes and then restart your engine running it up to about 2000 rpm's for about 3-5 minutes in a very well ventilated area. What comes out is burnt carbon buildup. I recently had some issues on my 22r that I thought were EGR valve related. IT"S FRIGGIN' SPOTLESS! It's a 93' with 72,000 on it. But I've used the SEAFOAM treatment on it regularly (every 3 months) for the last 7 years.
You can buy it at most autoparts shops. If not, try performance shops like Baxter Auto Parts.
L8TR, hope this helps!


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## i r teh noobz (Apr 26, 2007)

I just hit my 93 XE with Seafoam after pulling the original PCV valve at 116k. I only used about 1/4 of the can (it kept stalling) through the brake booster and I let it sit for the 5 minutes that it said on the can. I thought that my driveway would be alright, but I ended up fogging up the neighborhood and gagging some little girls that were playing in the alley. It smoked for a good 5 minutes, but it does feel a bit smoother now.


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## internetautomart (Mar 8, 2004)

:-\
I've got the seafoam here at work with me, I just don't really get how it would clean the EGR valve. Intake, exhaust and combustion chamber I can see it cleaning, but not the EGR valve. Anyone care to enlighten me?


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## dragontoy22r (Jun 27, 2007)

SEAFOAM is formulated in such a way that it enters and remains in the intake, exhaust and combustion chambers, as well as all orifices related to those areas. EGR is the exhaust gas recirculating back into the system. When you introduce SEAFOAM into your intake system, it needs to remain in your system just like any penetrant. SEAFOAM will enter the EGR system during the whole process and remain there when you the vehicle is bogged out or shutoff. I always allow about 15 minutes to let it soak and break up carbon. 
Sorry I didn't mention the smoke. The first time we used it in our shop was about 6 years ago or so. We used it in the bay and found that it was the biggest mistake we could have made. I do it in the driveway now.
It will clean your EGR. I recommend using it as often as you change your oil.


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## internetautomart (Mar 8, 2004)

the smoke part I knew. I just ASSumed that when it went through the combustion chamber it was ALL burned so it wouldn't make it back into the EGR system, hence all the purty smoke


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## vincega16 (Jul 9, 2007)

can you tell me where exactly do I feed the seafoam in a 94 nissan sentra GA16DE, and where is the EGR, I've seen it clearly on the SR20 Sentras, but not on mine...


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## pare_john (Jul 27, 2007)

HATEnFATE said:


> Remove it.


I want to try to word this so i don't sound insulting but when I read uneducated answers like this I get very upset. Removing the EGR will only hurt your engine and cause more carbon build-up in the future.

The EGR is needed, it helps reduce CC temps thus aiding in preventing predetonation and even detonation, also aiding in decreasing loss of energy through thermal energy. It also helps in reducing throttle loss by increasing the inlet manifold pressure. 

Please take no offense but instead try to be more informed before giving bad advice


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## i r teh noobz (Apr 26, 2007)

I fed my seafoam through the brake booster line, but I'd assume the PCV line will work as well. Just rev the engine by hand and suck in a few ounces (the car will probably stall a few times in the process). The EGR valve is under the intake manifold, near the air intake.


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## sfsentra (Aug 12, 2005)

I just Sea Foam'ed my '93 XE for the first time yesterday--and what a bunch of carbon it burned off! I haven't taken the car out to see if there's any noticeable performance benefit from the treatment, but I'm certainly a believer in the effectiveness of the product after yesterday's clear--actually, make that super-smokey!--demonstration.

Vincega16, look for the rubber vacuum hose that runs along the top of the firewall, and then turns straight down to connect to the side of the power brake vacuum booster (that's the round black item mounted between your brake master cylinder and the firewall). The vacuum hose has both metal and rubber sections as it runs along, so it should be fairly easy to identify. There's a 'squeeze' clip that holds the vacuum hose to the brake booster. Ease that off the end of the hose with a pair of pliers and up the hose a little ways--maybe a couple of inches or so. Then pull up on the hose to disconnect it from the booster. If your engine is running at this point, you'll hear a distinct 'sucking' sound as the engine pulls in air through the hose. Turn the end of the hose up.

I used a small funnel and stuck it into the end of the hose. Pour a small, slow but steady flow of Sea Foam into the end of the hose. The manufacturer suggests 1/3 of the can. When that's done, replace the hose onto the brake booster (don't bother with returning the squeeze clip to its original place at this point--do that when the entire procedure is completed). Turn the engine off immediately and let it sit. They say for 5 minutes. Then start the car. I let mine run at idle for a minute or two, then revved it. And that's when the smoke started! It took a few more minutes to clear off all the carbon, and I alternated between keeping the revs high and dropping it back to idle. Finally the exhaust ran clear again.

Let us know how yours goes!


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## sunnysentra (Jul 24, 2002)

interesting,

I never had buildup at all in the EGR. Maybe the valve was sticking or its shot. Plus, if the engine is out of tune or the vacume line is cracked going to the EGR or anywhere else, you will run shitty..

If the engine is out of tune, then more carbon will be sucked up into the EGR. make sure that the coil has a hot spark. these get weak over miles and loose the energy output. you need a new nissan coil after 80,000 miles. Then replace the cap/rotor/wires and plugs with OEM stuff. no aftermarket cap/rotors work and will crack. look for the the made in Italy on the cap. bosch caps and rotors are crap. By OEM only. 

anyhow, I used a product to get the carbon off the intake valves and piston tops. BG 44K. really works great. You can see the stamp# of the piston top when its gone through. My intake valves were so very clean when I pulled the intake manifold. 

One bad thing is the PCV and crankcase vent. They dump oil into the intake and when I removed and cleaned the plenum with a good acidic detergent, you should have seen the oil and shit coming out of the ports!! 

I am removing the all of the crankcase hoses from the valve cover and taking them to a Oil catch can with a breather filter. this works great and keeps that intake manifold clean. 

Chris 92 classic


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## i r teh noobz (Apr 26, 2007)

My catch can is always full of oily gunk. I'm glad I installed it.


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