EGR system

[Aurora40]

I've the '94-95 OBD-II style cable and can use it with Datamaster or the EZ-Scan 6000. You've got a PM.

[secondchance]

Last Friday I made an excuse to drive out towards Leesburg (not quite all the way but about half) since Route 7 is relatively quiet after Baron-Camaron. I opened her all the way up in 2nd and 3rd about half a dozen time.
On Satureday I drove out to Frederick, MD along I-270. After Gaithersburg traffic was relatively light allowing me to open up all the in 4th a few times.
This "petal to the metal" approach seems to have cleaned out most of, if not all, 4-5 years worth of DC daily commute carbon build up.
When hot I get split second of what sounds like a light pining around 2300-2500 rpm. Is this what you call a "tip-in knock", Kevin?

[QB93Z]

Originally Posted by secondchance

......On Satureday I drove out to Frederick, MD along I-270. After Gaithersburg traffic was relatively light allowing me to open up all the in 4th a few times.
This "petal to the metal" approach seems to have cleaned out most of, if not all, 4-5 years worth of DC daily commute carbon build up.......

Cleans it out and IT IS A LOT OF FUN!!!!

The knock that I was experiencing two years ago was not an "audible" thing. (At least not by me.) The knock sensor on the block is very sensitive. There were only a few (less than 10) detected knock counts showing up on the scan, but that is enough for the ECM to put in spark retard (lower the spark advance) and lower the power.

Jim

[secondchance]

Originally Posted by QB93Z

Cleans it out and IT IS A LOT OF FUN!!!!

The knock that I was experiencing two years ago was not an "audible" thing. (At least not by me.) The knock sensor on the block is very sensitive. There were only a few (less than 10) detected knock counts showing up on the scan, but that is enough for the ECM to put in spark retard (lower the spark advance) and lower the power.

Jim

Hey, Jim,

I will be replacing the chip w/ Haibeck version tomorrow (seems Phil has all the parts I need!). If there are any spark retard due to false knock, knock filter embedded in Haibeck chip should take care of it.

Last Friday I drove west on Route 7, passed Baron-Cameron, drove for a few miles revving up to 7000 in 2nd and 3rd a few times. Then I pulled a u turn and got on Baron-Cameron to go to Homedepot in Reston.
Along the way at the stop light 350Z provokes me. Well, I was out there to clean out carbon, right?

Well, I spanked him pretty good twice. He will be staying away from C4s for a while.

[Kevin]

Originally Posted by secondchance

I will be replacing the chip w/ Haibeck version tomorrow (seems Phil has all the parts I need!). If there are any spark retard due to false knock, knock filter embedded in Haibeck chip should take care of it.
.

marks chip will not get rid of the retard it will just reduce the amount of timing pulled and allow it to recover faster.

[Aurora40]

Originally Posted by secondchance

Hey, Jim,

I will be replacing the chip w/ Haibeck version tomorrow (seems Phil has all the parts I need!). If there are any spark retard due to false knock, knock filter embedded in Haibeck chip should take care of it.

Last Friday I drove west on Route 7, passed Baron-Cameron, drove for a few miles revving up to 7000 in 2nd and 3rd a few times. Then I pulled a u turn and got on Baron-Cameron to go to Homedepot in Reston.
Along the way at the stop light 350Z provokes me. Well, I was out there to clean out carbon, right?

Well, I spanked him pretty good twice. He will be staying away from C4s for a while.

Knock due to carbon buildup and such is not false knock. I'm surprised you can hear it though.

7 grand in 3rd gear!

[secondchance]

Originally Posted by Aurora40

Knock due to carbon buildup and such is not false knock. I'm surprised you can hear it though.

7 grand in 3rd gear!

First, demon I had been chasing was a real detonation, not loud but certainly I could hear it. At the time I replaced and checked all 2ndary vacuum lines under the plenum. It helped but could not totally get rid of pinging. At the time, the mechanic who worked on the car scanned and told me passenger side 02 readout was fluctuating (or comment similar to this) but could not offer any course of action.

Then about a month ago it got real bad (I could hear rattling noise). Simultaneously she would idle at 1000 then sputter down to 750 when the compressor kicked on, back to 1000 when compressor disengaged.

Finally, I concluded one of my primary injector went bad and on Sunday before last summoned all courage and dug in.

Pulling the plenum I discovered broken check valve stem, replaced both check valves, confirmed sealed vacuum and confirmed secondary flap actuation w/ vacuum pump.

I also replaced all 16 injectors.

Once buttoned up car ran infinately better and also high idle/idle fluctuation was fixed. However, when hot (207+ temp), I could still hear very muted pinging at 2300 to 2800 rpm under light throttle. A few excursions into 7000 seems to have pretty much cured this (probably blew out carbon deposits). However, I can still hear one brief ping when secondary seems to start coming on (2300 or so rpm). This may be what Kevin was referring to as "tip-in knock.

As for false knock(nothing to do w/ hearing it), I am aware that over active knock sensor falsely believe there is a knock when shifting at full throttle and retards timeing unnecessarilly. Haibeck chip has a filter to avoid this situation, from what I understand, maintain timing advance avoiding hp loss.