How much trouble is it to replace the egr valve. Its been throwing this code for a while now. I thought I could ignore it, but the car is not performing as it should. Nothing major, just not as much zip as it had before the code..

 

Not too bad. Then, after you get through throwing money at it, out of your system and you still keep getting the light, you'll have time to trouble shoot it to find the REAL problem. Don't shoot the messenger!

RACE ON!!!

 

The earlier c4's had an egr dianostic temp switch. These are the most common cause of the code 32 for the pre 90 cars. Check service manual and troubleshoot before throwing money at it.

 

What year is your Vette?
Does the SES come on at start up or after cruizing for a while?

There is an EGR system diagnostic method on my site that uses engine vacuum at idle.

 

Yes,the switch on the egr crossover tube started in 86 and on so his car wouldnt have it since its an 85.I got that mixed up once and a forum member corrected me on it.

My suggestions is to also check the vacuum lines and make sure none are broken.Its not a hard job to remove the plenum to access the egr but if youve never taken it off before,you will need some extra guidance in the steps.The forum will help.Im not sure of your mechanical knowledge so Im just pointing out the basics.Try and find out if its the egr causing the problem and not something else.

 

Indeed the '85 doesn't have the EGR Temp Sw on the EGR tube, it's located on the side of the EGR Valve base.

In fact it turns out that the EGR on an '85 is a pulse controlled system. If you shoot me an e-mail (jgkov@msn.com) refering to the is post I'll take a pic of the diagnostic pages in my '85 GM Shop Manual and return them to you.

 

I swear you are a WEALTH of Info.Its really good to see you offering endless advice on this forum all the time!
You really always go out of your way to help others when you can.
Heres to ya!

 

Thanks Bill, it's just part of life...an ongoing learning curve.

 

ENORMOUS trouble to replace; NOT in the ACTUAL replacement but in as much as you have to remove plenum & runners in order to gain access to it

 

Actually I have been to replace the EGR valve on my '86 IROC (same setup as on the '85 Vette) by just removing the plenum and using a very small open end wrench on the EGR valve bolts.

Of course a lot of PB Blaster on the bolts overnight along with a few hammer taps on the wrench helped free them up.

 

Yeah, OR you could do it THAT way! hehehe. Sorry; my head was full of 'excess thinking'! - I retract my 'ENORMOUS' statement and substitute it with 'Not very, but you still have to fork out for top of runners to plenum gaskets.'

 

My gaskets came out without damage. Maybe it was luck.

 

...It's not DAMAGE I'm talking about, as so did mine; but the gaskets are compressably and meant for 'one off' usage. Sure, you COULD use avaition gasket stuff or similar, but why suffer loss of power or rough idling?

Replace them with new ones everytime and avoid the headaches.
They're prob not too expensive to you guys in the states, but here in Australia I paid around AU$80 for a set.

 

I know you are right , but I am NOT the most mechanically inclined guy you will meet. Nor do I have a plethera of tools like a vacuum gauge and the knowledge to use it. From what I have read on other posts the valve should have nothing to do with the fact that the idle has become rough. To answer other questions, the light WAS coming on only after a ride on the freeway. Now it comes on after startup. Cold, hot , it does'nt matter, it stumbles when I give it gas for a split second. Rough at part throttle,smooth as glass on the floor

 

Hi mate; rough idle is typically a vacuum leak - this could also be the reason for the code 32 you're getting...

It may not be as bad as u think; try and visually check as thoroughly as u can, ALL vacuum hoses, for burns, cracks etc (Try disconnecting them at one end and blowing into the hose (I'd avoid sucking on the hose as some lines are part of your fuel system charcoal canisters etc and it can be quite nasty to inhale it - trust me I've done it! hehe).

Often a line will without you knowing it, burn through and then you have a vacuum leak! Discovered that myself once on the vac line that (used to) goes under the plenum. Or hoses also perish with age/heat.

I think you'll find with a bit of investigation; you can fix the problem by simply replacing the bad hose and your idle hopefully will get better AND the 'code 32' will dissapear. Remember to also clear any stored codes after you've located the problem, by disconnecting the negative battery lead for 15 - 30 seconds.

*Bad idle can also be caused by other things; inlet manifold leaks or burnt valves but vales you'd probably notice as a gradual loss of performance and idle quality; so MY bet is it's just a hose...

 

Someone said to spray some ether around the engine while it's running. It is supposed to speed up or smooth out when sucked into the leak. Any truth to that??

 

If you can,inspect the vacuum lines that connect the egr.
If theyre not broken,take the vacuum line off the egr valve itself and put a vacuum cap on it.Most auto parts stores sell a kit cheap with different size vacuum caps.These are handy for trouble shooting problems.

If you cap the egr off,what does it do?Is the car running better or worse?
Does it begin pinging at part throttle or no?
Does it stall or not?

Thats a big way to help with the problems.See,egr works only at part throttle,which is where your problem seems to be.At heavy or WOT the egr doesnt come into play and the car runs great.Just remember the egr works at part throttle to lower combustion chamber temps and emissions.

If not enough egr,the car usually pings and a loss of power is felt.Too much egr,the car stalls,runs rough and is annoying to drive.

On ther GM cars in the past,the egr valve was easy to access.One could put their fingers under the bottom of the egr plate and see if it would move up and down freely.I found stuck egrs that way.
The TPI makes it much harder to do that hand test so checking for broken vacuum lines or capping off the valve helps narrow it down.

Sometimes the valve is fine but when you take it off the intake,its full of carbon in the intake and the valve itself.Sometimes a good cleaning out of the carbon fixes it.

 

When the diaphram within the EGR Valve ruptures the resultant vacuum leak can play havoc with idle.

 

Yes; Some say mild soapy water, others say to use something like RP7, WD40 (Dont know what u guys in the U.S. have, but some of the normal water displacement spray from an auto shop); I think you'd be better to target an area tho, rather than spray the whole engine with it.

 

If you use a hand vacuum pump to test the egr and it holds vacuum, why is it that when you bump the starter the vacuum disappears from the hand pump? I've asked this question before and know one seems to know why.