Bypassing Egr Valve

[ONITSER]

I Have A 93 Blazer Lt, 4.3 Vortec. Is There A Way That I Can Bypass The Egr Valve.

[Fractured1]

Why would you want too...without it working properly you would end up with a check engine light...if you feel the EGR valve in not working try cleaning it first..There's several post in the forum on "how to"...

[BlazerLT]

Originally Posted by ONITSER

I Have A 93 Blazer Lt, 4.3 Vortec. Is There A Way That I Can Bypass The Egr Valve.

No.

EGR is part of your engine and is there for a reason. Leave it alone.

[ricksza]

Sure you can bypass the EGR valve. Just buy a block off plate from you local speed shop. While you're at it, buy a fresh motor too because the EGR valve is there to cool the combustion chamber so without it, you will hear a lot of pinging until the motor melts.

[BlazerLT]

Yip, leave it alone.

[tom3]

I've bypassed them to diagnose a faulty valve, engine runs fine but the SES light does come on. Gets to be a pain to keep cleaning it but I'd try to leave in operation myself.

[BlazerLT]

It isn't running fine.

Your knock sensors will be detecting ping and retarding your timing therefore killing your power and fuel economy.

[Fireplug]

You also forgot that a 93 with the check engine lite on will go into open loop = poor fuel milage

[MRogers]

Can someone explain why letting hot exhaust gases in is going to cool the combustion chamber? I beleive it is actually just part of the emission system.

[metallica21156]

if you want it to run cooler then get a EGR gas cooler or make a cutoms one to fit on there. think it uses the existing coolent to cool it. don't know if it works.

[BlazerLT]

Originally Posted by MRogers

Can someone explain why letting hot exhaust gases in is going to cool the combustion chamber? I beleive it is actually just part of the emission system.

Exhaust temperatures are a lot cooler than combustion temperatures.

It is like you are saying the smoke is hotter than the fire.

[Mikado14]

Originally Posted by MRogers

Can someone explain why letting hot exhaust gases in is going to cool the combustion chamber? I beleive it is actually just part of the emission system.

You are reducing the amount of oxygen for combustion by introducing inert gases from the exhaust which reduces the combustion temperature. By reducing the combustion temperature, the amount of NOx emissions are reduced. Oxides of Nitrogen are the main component is smog. The EGR is purely an emissions device and not performance.

[Fireplug]

Mikado14
I would agree with everything you said and would add that by lowering the combustion temps that also reduces the chance of piston ping and that alone will help performance

[metallica21156]

so does the EGR mod do anything or just nothing at all?

[BlazerLT]

Originally Posted by Fireplug

Mikado14
I would agree with everything you said and would add that by lowering the combustion temps that also reduces the chance of piston ping and that alone will help performance

Actually, it is also used as a anti detonation/ping system too.

Read this:

http://www.autoshop101.com/forms/h61.pdf