Real Fiero Tech

Mach10 wrote:Curious: How does the ECM know that the EGR isn't working, as long as the EGR solenoid responds normally (which it will do assuming only the exhaust port is blocked off)?

When the EGR is opened, the pressure in the intake manifold is supposed to increase. So if the MAP doesn't respond appropriately - SES light.

That said, there are all sorts of circumstances that can circumvent this check. So yes, it can cause you to go lean. It's kind of like relying on the knock sensor when running mexican 70 octane. Disabling the EGR in the chip is the best way to do it.

Mach10 wrote:Curious: How does the ECM know that the EGR isn't working, as long as the EGR solenoid responds normally (which it will do assuming only the exhaust port is blocked off)?

I believe it looks at change in mixture vs MAP. I think more modern computers with knock sensors do a ping test by diddling with timing.

The Dark Side of Will wrote:Basically, blocking the EGR passage will cause your MIL to light on the highway when the computer realizes that the EGR is not working.

Whats a MIL?

Shaun41178(2) wrote:Make plates for the intake to block off the egr.

Where exactly do you recommend installing the plates? Also where did you get your plates? Can you help me to acquire them also?

That is what I like about my Quad 4, no EGR, no PCV, no breather thing, just a wierd air/oil seperator, which is pretty much maintanence free. :thumbleft:

Malfunction Indicator Lamp
CEL - Check Engine Light
etc.

Aww man! So i removed the plennum, installed a block off plate, removed the egr valve (exhaust block off plate being installed tomorrow), followed all vacuum lines that i can think of and capped off the necessary lines, re assembled the motor and started it up again. Now when i plug the whole in my throttle body it doesnt affect the idle at all! To top if off the exhaust headers still start to glow red hot if i leave it running... :cussing: Help!!! Any other suggestions? NW fiero owners i will PAY you to come help me in Kitsap!!!

did you check fuel pressure? you could be really lean.

I am betting you have a bad vacuum line or you didnt' reinstall something correctly. The car should stall when you cover the iac hole in the tb. so air is getting in somewhere.

Did you use new gaskets?

Spray some carb cleaner around the intake and if it stumbles then you found your leak.

p8ntman442 wrote:did you check fuel pressure? you could be really lean.

How do i check the fuel pressure?

Shaun41178(2) wrote:I am betting you have a bad vacuum line or you didnt' reinstall something correctly. The car should stall when you cover the iac hole in the tb. so air is getting in somewhere.

Did you use new gaskets?

Spray some carb cleaner around the intake and if it stumbles then you found your leak.

What do you mean by bad vacuum line? To the best of my knowledge all the lines are installed properly.

Whats IAC stand for?

Didnt use new gaskets because the gaskets that were on there looked to be fine. Not worn at all.

CAn i substitute the carb cleaner for brake cleaner?

1) Get a fuel pressure gauge and hook it up to the fitting on the fuel rail nearest to the thermostat. Turn key on so fuel pump comes on and take reading.

2) Bad vacuum line means cracked vacuum line. They have a tendancy to crack lengthwise, so even though one isn't broken in half, it may have a crack in it that you wouldn't normally notice.

3) Its best to use new gaskets, but at least make sure everything is torqued down right so your old gaskets are less likely to leak.

4) Yes, you can sub in carb cleaner for brake cleaner in this case.

My last fiero would glow red because the timing was off a good deal. (friend scrapped off my markings)

Alright so got the intake side of the egr blocked off using the soda can method, buddy of mine mad a block off plate for the exhaust side(removed the egr valve), followed the line and capped that off, replaced the intake manifold gaskets, started up the engine and it still leaked. I would plug the whole in the throttle body(whats that called by the way?) and the car would still run fine. NOT GOOD. Took off the intake manifold again and that plug to the throttle body was very lose and appeared to not be in. Stuck it in, put some rtv around it and BAM exhaust no longer glows. MISSION ACCOMPLISHED!!! Only thing left is my timing. Gonna go work on that now. THANKS EVERYONE!!! :thumbleft: