EGR Routing
Thread Starter
Racer
Joined: Oct 2001
Posts: 262
Likes: 0
From: Palos Hills IL
CFI-EFI - Ok. So in other words, it doesn't matter, correct?
If I hook up a vacuum gauge to the side that goes to the egr and tape it to the windshield, at cruise speed I should see some vacuum, correct? I'm trying to figure out why I'm getting knock at about 4k under acelleration. Jesse seems to think he has enough fuel in the chip he did for me. I just trying to check all avenues before having him add more fuel via the chip. Jacking up fuel press. with the reg. makes no difference. Knock will go away if I reduce timing from 6* to 3* or if I add the good torco octane booster, which I really don't want to have to do either. Any other ideas, I'm certainly open to listening to. Thanks
If I hook up a vacuum gauge to the side that goes to the egr and tape it to the windshield, at cruise speed I should see some vacuum, correct? I'm trying to figure out why I'm getting knock at about 4k under acelleration. Jesse seems to think he has enough fuel in the chip he did for me. I just trying to check all avenues before having him add more fuel via the chip. Jacking up fuel press. with the reg. makes no difference. Knock will go away if I reduce timing from 6* to 3* or if I add the good torco octane booster, which I really don't want to have to do either. Any other ideas, I'm certainly open to listening to. Thanks
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Just throwing other ideas around...has this always happened with your engine or something new?Is it part throttle ping or WOT?
Do you have a scanner to use while driving?If not that would help alot too.
Was your cam installed a certain way?Are you hearing it ping or is the knock sensor retarding the timing where the car wants to slow down some?
Do you have the correct heat range plugs for your engine?
See,I find it a bit hard to beleive the egr could affect the engine that much,especially if your engine build up in your sig is what you have.
Not enough EGR usually causes the pinging/detonation if everythings in check.I noticed most modded engines dont even need it anymore unless inspection requires it.
Just throwing the ideas around...im sure the othes will help.
Do you have a scanner to use while driving?If not that would help alot too.
Was your cam installed a certain way?Are you hearing it ping or is the knock sensor retarding the timing where the car wants to slow down some?
Do you have the correct heat range plugs for your engine?
See,I find it a bit hard to beleive the egr could affect the engine that much,especially if your engine build up in your sig is what you have.
Not enough EGR usually causes the pinging/detonation if everythings in check.I noticed most modded engines dont even need it anymore unless inspection requires it.
Just throwing the ideas around...im sure the othes will help.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Kwik88
CFI-EFI - Ok. So in other words, it doesn't matter, correct?
If I hook up a vacuum gauge to the side that goes to the egr and tape it to the windshield, at cruise speed I should see some vacuum, correct? I'm trying to figure out why I'm getting knock at about 4k under acelleration. Jesse seems to think he has enough fuel in the chip he did for me. I just trying to check all avenues before having him add more fuel via the chip. Jacking up fuel press. with the reg. makes no difference. Knock will go away if I reduce timing from 6* to 3* or if I add the good torco octane booster, which I really don't want to have to do either. Any other ideas, I'm certainly open to listening to. Thanks
If I hook up a vacuum gauge to the side that goes to the egr and tape it to the windshield, at cruise speed I should see some vacuum, correct? I'm trying to figure out why I'm getting knock at about 4k under acelleration. Jesse seems to think he has enough fuel in the chip he did for me. I just trying to check all avenues before having him add more fuel via the chip. Jacking up fuel press. with the reg. makes no difference. Knock will go away if I reduce timing from 6* to 3* or if I add the good torco octane booster, which I really don't want to have to do either. Any other ideas, I'm certainly open to listening to. Thanks
Yes, on the vacuum showing on the gauge, at cruise.
Is the "knock at about 4k under acelleration", at WOT? There is virtually no vacuum at WOT. And even "under acelleration" at less than WOT, the vacuum is severely reduced.
Since increasing the fuel pressure doesn't affect the knock, chances are, Jesse is right. The only way to know for sure would be to run it under varying conditions with a wide band O2 attached, so you can SEE what is happening with the fuel, rather than speculating. Based on everything you've written, it is the timing curve that needs attention, not the fuel curve.
RACE ON!!!
Thread Starter
Racer
Joined: Oct 2001
Posts: 262
Likes: 0
From: Palos Hills IL
That's the first conversation I had with him. He seems to think the chip is pretty much right on. That's why I'm looking at everything else I can, such as the egr, plugs ect. No, no codes. But if I put direct vacuum to the egr while the car is idling, shouldn't the car stumble if the egr is made to open, or I should say 'IF' it's opening. I put a new solenoid on it today. I ran the vacuum line from the throttle body to the back port on the solenoid and hooked a vacuum gauge to the port where the egr line should go. I then taped the vacuum gauge to the windshield and drove the car around under different cruising speeds. It never showed any vacuum on the gauge, why not?
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Race Director
Joined: Aug 2000
Posts: 14,130
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Cruise-In II Veteran
Originally Posted by Kwik88
50-60 mph and 190-200* What is the port for that has the little foam filter over it?
Why are you worried about a piece of foam on the solenoid when you are avoiding alot of questions?
Anyways,cap your EGR off with a vaccum cap.If the problem stops,or gets better,you found your answer.
Thread Starter
Racer
Joined: Oct 2001
Posts: 262
Likes: 0
From: Palos Hills IL
Bill - As far as the foam filter, I'm not 'worried' about a foam filter. My question was about the port it self. By the way, do you know what the port does? The cam was degreed in using the cam card from cam motion. The knock can be heard, under wot or just a gradual climb in rpm. The plugs are ngk fr5, recommended by jesse. Never had the problem before, it's just been after the cam install and valve job. As far as the egr, no I don't know that that's the problem, that's why this is a pita, I'm not sure what the problem is.
Drifting
Joined: Mar 2005
Posts: 1,923
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From: GA
Originally Posted by Kwik88
Bill - As far as the foam filter, I'm not 'worried' about a foam filter. My question was about the port it self. By the way, do you know what the port does?
Instructor
Joined: Jun 2005
Posts: 193
Likes: 0
From: woodinville washington
try testing the solenoid off of the car, not plugged in, apply vacuum through the solenoid, even just sucking on one end and pluging the other, there should be no air comming into that foam filter side, if you suck on the throttle body side while plugging the manifold side you should not be able to suck, it should feel completely plugged.
many times that foam filter outlet will not seal while the egr is activated, this causes a leak when the vacuum is trying to open the valve and therefor the valve will not open. then replace the solenoid.
