I haven't hooked up my EGR valve yet because I broke the hoses and don't have new ones yet.

The EGR solenoid is activated by the Exhaust Gas temperature sender, which is on the right side of the engine next to the distributor. I didn't hook mine up, decided that if it is unhooked, the computer will either try to activate the EGR because it thinks the exhaust is REALLY hot, or it will leave it closed because it will think the exhaust is REALLY cold. It appears as if it is the latter of the two.

I hooked up the EGR solenoid so that the computer will complete any sort of loop there, but it is not hooked to the EGR in any way.

After 3.9 hours, still no codes. :)

I'm torn between hooking the EGR up permanently or just when I need to pass emissions. It does such nasty things to the inside of the plenum/runners/intake valves that leaving it unhooked is really the only healty option.

Just FYI.

 

you broke those damn little fragile vacuum lines too huh

 

:reddevil :) ;)

 

where are you getting new ones at?, btw, ive left mine disconnected for the time being (a couple of weeks), and my intake is still clean on the inside, this was verified today. so im thinking of just hooking mine back up when needed too. i still need to find those damn little lines somewhere though.


[Modified by 88L98, 4:58 PM 10/11/2001]

 

I'm thinking I'm going to have to make a set, thats how I did the fuel pressure regulator, which is the only vacuum port hooked up on mine right now, all the others are capped.

 

Just so you know the EGR does not quite work that way. Furthermore it does very little harm to performance. Even furthermore, if you remove it to gain some performance you have to mess with the code tables to insure proper mixture and timing in the mid-range (which is were you get your SOTP), or there will actually be a reduction of performance. Not much to be gained for the work, really; and EGR does nothing at WOT.

EGR operation is a function of the tables in the ECM having to do with RPM, load, temperature, and some other parameters.

Removing EGR can also be a problem (other then performance w/o reprogramming). EGR reduces combustion temperatures, and without it knock is more likely. Knock will cause knock retard - which will pull back spark advance and cause .... reduced performance. If knock cannot be prevented (ECM expects EGR to work) then damage to the engine can result.

Much better things to work on, IMO>

Pete

 

i dont have mine removed by choice.

 

Not an attack, just to make clear to the 10,000 that read and don't post that this is not clearly a great position to be in!

This post was not directed to you, just in general.

You can get a minimal improvement in power by removing the EGR function, BUT you need to reprogram the ECM to cover loss of this engine management function. Also it needs to be noted that NOx emissions will go up, for those that have to be tested.

Cheapest thing is to fix the EGR circuit, alternatively you could remove it cleanly and get a chip programmed to cover this function. But you will still have to deal with knock or loose some advance in timing (and deal with emissions if necessary).

Peace. If I were young and broke again I will deal with it anyway I had to. :cool:

 

Just some more backup of what PeteL said...
http://autorepair.about.com/library/.../bldef-176.htm http://autorepair.about.com/library/.../bldef-165.htm

I would make sure mine got hooked back up asap.




[Modified by TJR, 1:37 AM 10/12/2001]

 

My old 88 305 TPI IROC had an EGR solenoid failure while I was making a cross country trip... I drove from CA to GA in 3.5 days...

Other than the SES light for the EGR, the car ran perfect...

My car had the 305, A4, and 2.73 highway gears... Running 80MPH with the A/C on constantly (summer)...

Before the failure, I averaged 27MPG, after the SES light, the car averaged 30-31MPG and ran much better as far as responsiveness and SOTP feeling...

When I got to GA, I had the solenoid replaced at the dealership for an unholy amount of money and my economy dropped back down to 27MPG... Very disappointing... I thought about making some kind of electrical load to take the place of the solenoid (for the SES light) but never got around to it...

I made a block off plate for my 96 LT1 and the car ran better for about 4 days before the ODBII set of an SES light... Unfortunately on ODBII, the MAP checks for intake vacuum/pressure differences when the EGR is opened so I set a P0400 code when the computer didn't see the EGR functioning properly, so I had to "normalize" it... :(

Both cars did run better and have better ecomony with the EGRs disabled...

With your ODBI car I don't think you will have any problems...

 

understood, i didnt mean my comment as if you were trying to slam someone, i was just sayin i was out of an egr with no choice. the little plastic vacuum lines that run to the egr soleniod are VERY fragile, i was taking my intake off to port it and the thing snapped in two places at once when i tried to move it with very little force. it is a very cheap repair, i could just buy cheap small vacuum lines and use them in place of the hard lines, but ive been trying to locate the hardlines with no luck. so i guess its going to be some rubber vacuum lines instead.

 

Best way, is to get a custom ePROM chip for the ECM that leaves the EGR alone. At the same time, the chip should be optimized for more fuel delivery, to keep things cool, and air-fuel ratios satisfied. When smog testing comes around, or resale, just plug the stock chip in. Good luck! :flag