Looking into the issues with my car, I discovered something interesting. I always wondered why Adam's and MRink's logger never had any garbage packets, but mine did. In other words, at random times, my logger would show really off the wall values like 104 knock and 400 degress timing. It's made tracking my issues much harder than need be.

I've been talking with Rob Beck, and I believe we have found the fix. We believe the issue is caused by the fuel pump relay.

http://www.team3s.com/~egross/3S/Mods/T ... rcuit.html

The fuel pump relay is controled by the ECU to direct power to the fuel pump resistor which simply lowers the power output to the fuel pump. In other words, this means less fuel when you don't need it.

http://www.team3s.com/~egross/3S/Mods/T ... twire.html

Now, when you hotwire the fuel pump, you completely bypass the stock wiring with a 8 gauge wire directly from the battery to the fuel pump and splice in a generic 12V relay to activate the fuel pump when the ignition is turned on. This way the fuel pump will always get full voltage no matter what because the fuel pump resistor is bypassed, and you don't loose voltage from the tiny stock wiring.

The stock fuel pump relay uses a 5-6volt trigger and the relay typically used in a hotwire is 12volts. We believe this somehow creates the garbage packets in the ECU (still looking into why exactly this happens).

The fix is simply to pull out the stock fuel pump relay and bypass the resistor. http://www.stealth316.com/2-fuelpumprelaybypass.htm

Doing this on my car and Robs car completely eliminated the strange logger readings. Didn't fix the knock problem on my car, but now I can get a decent log without the BS.

In other words, if you own a 94/95 car and do the direct hotwire, do the resistor by-pass as well or you could get strange readings on the logger.

Thought maybe some of you electrical engineers would be able to help us understand better why exactly this happens.

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06 Blue EVO 9

more great info from greg. That might explain why i was having 40 counts of knock or more when my car ran this summer, only a 3rd gear pull at maybe 70% tps, but i didnt log it. Now that i think of it, i think i did have a log from a wot that i MIGHT have done, but its a little too late now. Reason i wasnt able to look at it all was because my computer was down at the time. I guess ill be doing this for sure and see if i can get that long on my computer.

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1994 Stealth R/T TT Pearl Yellow
-Out since June 05'
-Almost ready for start up

1991 Stealth R/T Red
-Out for 7 weeks with a spun bearing
-Came back to life on 8/04/07
-Blew the motor again on 11/25/07

Interesting. Nice post Greg. I'm using the RDR rewire and haven't had an issue (beyond the logger's poor resolution and the fact my MAF always seems to read 1604 at WOT):
http://www.team3s.com/~egross/3S/Mods/T ... ewire.html

I still need to do the optional run of 10g wire to reduce the voltage loss due to resistance, so I'll keep an eye out after I do that.

The problem must have something to do with feeding the Hot Wire relay with the resistor output as the source.

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Christopher

Don't have this problem with the relay and the resistor still serving duty.

I would like more info, such as type of relay that you both used, and what palm, how old the cable is... I'm not convinced. sorry Greg.

_________________
Bad decisions make good stories.
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Same logger you have. When I use it in the SL, I don't get garbage packets.

I used the relay that comes with the DR kit. DR now offers a different kit and I don't know if it uses the same relay. FWIW, it looks exactly like the one you have.

Verfer's and your car do not have the direct hotwire like mine. You guys did it the hard way. MRinks car is stock, and he also doesn't get the garbage packets.

FWIW, couple weeks ago I logged a peak 209 knock count. The one and only time I've ever seen a peak number above 10 on there. And I had barely pulled out on the street, normal driving conditions.

Let's check your grounds.

nien.


huh? mines wrapped under half a mile of tape right next to my stock one. Did I unwrap it and show you it at the 60k service? cause I don't remember that. I remember you commenting about my retarded way of running the power wire for the pump inside the car, but not showing you the relay...?


if it was easy, everyone would do it.

How did you do yours. I posted more of an answer on us3s. if I feel ambitous I'll copy it over here... later.

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

From the link above:
http://www.team3s.com/~egross/3S/Mods/T ... twire.html

You showed me the relay one time when I was up there. This was before you moved to your parents house. ...or maybe I'm on crack. At any rate...

The fact that you don't get the junk packets and I do only reenforeces my claim that this is only an issue with car with the direct hotwire.

Did I have the relay in my hands, as in "not on the car?"

cause then it was a stock fuel pump relay from a toyota dealership with the nubs cut off it. I only have one relay for the bypass, and that's on my car. never had a problem with that one yet...

I thought you said that the direct hotwire got rid of the junk packets...

reading >> me.

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

So now my question mister MSOE grad man. How could feeding the 12v relay with the resistor output comming from the 5 volt stock relay cause this?

well lets see here. since reading has never been my strong point, I'm gonna go from memory again, and probably make myself look like even more of a 'tard. (can we say that on the internet?)

The eric gross method that I did oh so long ago had me cutting wiring for the stock relay to fire the new one. reason being, (as you know, but I'm typing out loud here) that the fuel pump even on full throttle would only recieve 10~11 volts through the stock wiring. This relay was activated by the MFI relay, I believe... meaning the relay saw more than 5 volts to trip it, didn't it? Or not?

Lets take a time out and look at this for a second, though.

If the MFI relay trip signal is only 5 volts, then perchance that is the problem, as the relay is probably a 5-12 volt trip relay. so then the 5 volts is right on the edge of not tripping it, which may make the relay "chatter" open-close bazillions of times a second, or at least when you first get on it. Every electronic circuit makes an electric field, and perhaps that "chattering relay" is causing some really goofy electronic interference.

but that also means that mine should do it, unless the relay is different, such as a lower trip value... but it should be the stock relay...

So what else could be causing this? Does the ECU have anyway of knowing when the curcuit switches or is activated? when do you get the garbage packets? all the time, random, cruise, full throttle?

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

sure, though pin 31 (i think, on erik's (soory, been speeling it rong!) site that's the call out.) the ECU will see what she's doing.

Also, it looks as though the power runs through the MFI relay, then to the pump, via connection 5. correct? I dunno, but I'm gonna continue as though I am. HA!

So your relay should be seeing somewhere between 9~14 volts through the trip mechanism. probably somewhere wound 10 volts, like erik measured at the pump. this means that there should be more than enough to trip a 5 volt relay.

the signal must go through a resistor before it goes to the ECU to go back down to 5 volts.

Perhaps by hooking both wires to the same relay, and then to ground, your changing the impedence or resistance of the curcuit, and that is affecting the signal (seeing as it's the same curcuit/wire) and that's screwing with the signal that the ECU is seeing. remember, you change the impedence or the resistance, and suddenly the resistor that should knock the 9~14 volts from the MFI relay is now doing something entirely different with that voltage/signal.

now the ECU probably sees it as an on/off sort of thing, but if the voltage is jacked high/low, it may screw with other things in the ECU.

my best guess as I sit here hung over right now...

_________________
Bad decisions make good stories.
Look at it! LOOK AT MY @SS AND TELL ME IT'S PRETTY!

Garbage packets come in open loop (accelerating) when the ECU should switch the relay to bypass the pump resistor.

Found something very intresting.

When we switched my ECU into Unclebenny's car (97 VR4), he also got the garbage packets. His fuel pump is directly hotwired like mine. We're going to pull the fuel pump relay and see if this gets rid of them like my car.

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06 Blue EVO 9