Magnet

iTrader: (36)

My dads car is running really strange. I logged it tonight and it barely spins the tires and then runs ok, then shifts into second and all the sudden the pedal drops and the motor doesn't go anywhere. Its like its hitting traction control, but it is unplugged under the hood. It is also running 15.5* of spark WOT and getting a consistent 4KR. I beleive the KR is from the Y-pipe resting on the floor, which we will hopefully fix ASAP, but that shouldn't make the car stall more or less as soon as it goes into second gear would it? If you get out of it and then hit it again it pulls pretty good, its just if you stay in it from first..

BTW this is on a stock tune minus my fan settings and speedo recal.

I'm lost

Magnet

iTrader: (36)

Help please

2xLS1

iTrader: (25)

Is it setting a knock sensor code by any chance? It has some big time torque management going on during the shifts

Magnet

iTrader: (36)

No codes, and I disabled TM at one point when I was playing with it and it was still doing that..

I also unhooked the traction control under the hood.

The only thing I can think of is if like your saying the headers are creating such a horrible "knock" that the knock sensors are freaking out, but are they that severe??

Frost

iTrader: (45)

I think it's this too^

Every time I see that straight max retard amount present in PE, it's in the knock sensor or wiring.

Magnet

iTrader: (36)

Could that be caused by the Y-pipe literally resting against the body? Or is it the knock sensors/ wiring themselves?

It isn't throwing any codes according to HP tuners..

slo98bird

iTrader: (4)

im somewhat interested in this also, how much does it hurt the performance when it pulls timing from it hitting? whats the best way to remidy the situation? subscribed

Frost

iTrader: (45)

It's not sporadic, it's constant. Pipes don't just constantly bang only in PE

Magnet

iTrader: (36)

Soo.... Were saying it's the knock sensors or wiring themselves.. Lol. I'm gonna try and remedy the y-pipe situation today, even if it's just a temporary fix, and see where that gets me. Then, if it's still not right, I can do a test run with the knock sensors deleted in the tune to see if that's causing the problem.. If so, replace

Sound like a plan? Any tips on disabling the knock sensors temporarily to trouble shoot?

2xLS1

iTrader: (25)

First provide some deails on the car. Why do people always ask for help and give no details on the car. The airflow in the log file histogram looks high for a stockish car. But then again we have no idea what has been done to it. Also from the log you posted the tune is not as stock as you stated. <<BTW this is on a stock tune minus my fan settings and speedo recal.>> The commanded A/F in PE in the log is not stock for a 01 F-body that the log IDs the car as. You obviously have the ability to post the .hpt tune file so why don't you? You could have something jacked up in the tune.

Magnet

iTrader: (36)

Thanks for the response, but no need to get irritated. This log must have been with the tune I put in it, but I went WOT with the scanner and it did what I described above, so I threw the stock tune back in to trouble shoot, scanned it, and it did the exact same thing. This leads me to beleive it wasnt the tune

The car has:
UDP
LT's into stock exhaust
Stock everywhere else including lid/ filter..

EDIT: Also has a Yank SS3600 and built transmission

James Linder

Maybe you unplugged something you shouldn't have. Evidently your car does not have the interior shut off switch on the dash like the typical LS1 FBodies from 1998 (possibly older) through 2002. I would be damn certain what I unplugged is not affecting more than the traction contol. If you have manual transmission then I am not familiar with how your car may be configured from GM - my reference is to the automatics like mine.

Magnet

iTrader: (36)

You can unplug the connector going into the black box thing under the hood, all it does is kill the TCS without having to flip the switch. It normally pops the light on the gauges though...

The car is an M6converted to A4 Btw.



I logged it again today, and it popped some codes, I'm not sure if didn't read last night or if they came today.. Im not sure what they stand for?

Golf&GM

iTrader: (22)

The P0327 code and the symptoms lead me to believe you really need to replace the knock sensor. I highly doubt a banging y-pipe is going to cause what you're talking about, I had a horrible y-pipe banging issue but it never caused a knock sensor code or caused my car to run as bad as you're describing. Sometime sensors don't go completely useless all at once, sometimes they come and go which could explain why it runs ok sometimes. Usually any sensor that throws a "circuit low voltage" code is an indication the senor is on it's last leg.

EDIT: I'd also say your [Brake] C0550 code could be a result of you unplugging the TCS. The other U codes are common when you reflash the PCM, they'll go away after you drive the car a while after tuning.

James Linder

Plug that thing back in under the hood and flip the switch inside
to disable TC and try this to make certain it does not change anything.

And please post your timing curve so I can see how much timing
you have dialed in across the loads verses RPM.

Please also post your MAF curve verses Hz. Are you sure your
fuel filter is not plugged up. If you let these get bad you will run lean and after enough time it will cause your fuel pump will go bad and you have to take the fuel tank off to put a new one in - what a hassle.

James Linder

Just to be clear, an exhaust pipe banging can certainly trigger the knock sensors, this is widely accepted and documented. This is because this knock is a a frequency close enough to that of the piston knock the sensor is designed to detect. These sensors are designed to detect knock so slight that you could not begin to detect it with the human ear, and the knock so loud that you can hear due to your exhaust pipe is probably causing them to go nuts with retarding your timing. Eliminate the exhaust pipe banging before jumping into any conclusions about replacing the knock sensors. Be sure and check to make certain your transmission mount is not broken because this will certainly allow the y pipe to hit the body (under driver side seat) when you get on it and torque the engine up. check with Frost and make certain the PCM you are using with the automatic that was meant for a manual will work as long as you have it programmed correctly - this is beyond my experience.

Magnet

iTrader: (36)

The brake light has been on in the car since we got it, and the e-brake doesn't work at all so I figured it was to do with that.

The wiring to the switch inside is all shot, the people before us had a grand old time cutting wires when they were hooking up a terrible aftermarket stereo

I can upload the MAf and spark curves if you really want, but they are stock 01 automatic...

Good info. The trans mount is a brand new prothane, so its not that, but the y-pipe doesn't bang like I have seen in some cars, it literally rests against the body, right where the pacesetter y-pipe is smashed, which vibrates it pretty bad..

Were thinking the y-pipe sitting where it does could be from terribly worn motor mounts..

James Linder

Fix the banging exhaust pipe and then we can talk if you still have problems.

Magnet

iTrader: (36)

Your pretty direct there buckaroo, I can't really complain since your helping me out though. Lol

We may be putting motor mounts in it, I'm not sure what else to do about the y-pipe. The same headers and y-pipe have been on two of our other cars, and neither had the clearance problem, so it has to be something about this car..

Frost

iTrader: (45)

It's not the Y pipe! It's clear in the log too.

On top of the quoted, P0327 means the sensor or the wiring has failed open.