30th t/a

iTrader: (51)

[QUOTE=Bad30th;

Edit : hmm, looks like it's doing it with the MAF unplugged so I guess that may not be it... However, getting different results with your friend's tune and his car having problems with your PCM/tune kind of points in that direction... It's also still possible you fried something in your PCM when you were soldering the wires, right ?


Rob (Bad30th)[/QUOTE]

I thought about that too but when I ran my buddys PCM my car still cut out and fell on its face at the same RPMs. The guy that tuned it said being that the tune is different...thats probably why it didnt backfire & shut down.

you are correct though, there are times where I ease into the throttle and I watch the tach hit 5000 & 5500 rpms. But when I "drop the hammer" 3000 or so rpms, it just starts breaking up like no tomorrow and other times hit will hit 4500 or so and just "cut" completly out and fall on its face, thats when it backfires.

edcmat-l1

iTrader: (10)

Ya'll are killin me with all the guessin, and nobodys diagnosin nothin.
There is a systematic, methodical process to diagnosing any type of problem.
In a nutshell, it is acquiring and analyzing data.
What kind of equipment are we using to gather the data? None? No scan data? dont think that will mean anything anyways. No scope to watch the sensor signals?
You may luck out and stumble upon it in time, but using a systematic, methodical approach will get to the bottom of it in a reasonable amount of time.
As far as what it COULD be, it COULD be secondary ignition breakdown. It COULD be a bad connection almost anywhere. It COULD be a cam or crank senor issue, which COULD involve a mechanical issue.
Ask yourself 'how can I DIAGNOSE this?'

30th t/a

iTrader: (51)

I cant DIAGNOSE this. I dont have the scan tools, I dont have the knowledge of using any of the special tools you've listed and I dont know anybody that can diagnose this with those tools that youve listed.....other than people that are 10 hours away from me.

The guy that tuned the car told me to take it to a dealership. So I did. That was a waste of time. I paid $80 to hear "our scan tool wouldnt work with your highly modded car, it was ment for a stock LS1"

I wish they could have told me that ahead of time. Im sure that could tell the car was modded when they started it.

Frost

iTrader: (45)

There is more than 1 good tuner in your area that will likely do some scanning for an hourly fee to help you determine what the issue is... You are in PA not Alaska, why do you say 10 hours? It's kind of hard to have a car as modded as yours and not have any way to talk to the PCM. With all of that cash in setup, why no tuning/scanning suite?

edcmat-l1

iTrader: (10)

The ten hour deal is he talked to me about bringing it down. Looks like I'm about 8+ hours away. Probably longer towing.
But yeah, he needs some software, and somebody good to be looking at it.

30th t/a

iTrader: (51)

Actually the 10 hours was just being sarcastic. It just seems that all the really good shops that are sponsors are so far from me. im going to do some looking around this area for someone that can diagnose this problem for me.

Abe99

iTrader: (2)

I have the same problem. I have replace some of the wiring to the crank position sensor (piece was slightly burnt), replaced CPS and did a relearn. I have also changed the coil packs, injectors, disconnected the MAF and changed the O2 sensors. I am planning on buying HP tuners or EFlive so I can log some the data. Let us know what you find out.

30th t/a

iTrader: (51)

wow there are 3 of us now
yea, ill definately update the thread when I find out the problem please let me know if you find out anything.

NoGo

iTrader: (2)

My advice is to put the stock size injectors back in, flash that PCM back to stock (at the dealership), and spin it up. It may be a little lean/rich for that run, but it won't hurt it. The car should at least spin up and run semi-normal; especially at WOT. This will eliminate the PCM, and tune as the issue.

If it still does it, you know it is a wiring/sensor/reluctor problem on the car.

CompCamaro

KcFormula an I will post some log info, an try not to get so tied up in shootouts. I will be out of town this weekend, so time is now an issue(maybe the weekend after).

KCFormula

iTrader: (4)

I wish I had the last datalog of your car but I reinstalled windows and lost it. I do remember it had split BLMs but I don't think that had anything to do with the backfireing.

30th t/a

iTrader: (51)

I believe I fixed the problem!! (dont wanna get too cocky yet)

2 things...As many of you have read, I said replaced 100% of the crank sensor wires, I should have rephrased that and said 99% because up until today I replaced all but the crank sensor pigtail. So I soldered a new pigtail in today. Also, the head on the bolt for positive battery terminal is rounded off...bigtime. So today I tightened it as much as possible with the 5/16" wrench and I noticed the cabel wasnt as tight as I thought it should be so I got some pliers and tightened it up so very tight. Before I was just tightening the bolt up with the 5/16" wrench and I thought that was good enough.
Well I just went for a test ride and all was good! I took it to 6000 without a miss. Talk about being happy!!! Damn I freaking out!

thanks for all help guys!!!

bboyxclub

iTrader: (2)

Finally my friend I'm glad for you; good thing you got that fix in less than two months or I would have been worry Amazing to think that it was so simple.

30th t/a

iTrader: (51)

Thanks. I knew it would be something simple and cheap. Electrical gremlins are the worst! finding the problem without a scanner is the hard part. I had a appointment to take my car to a LS1 shop next saturday too. Wont be needing that now

01 BERGER CAMARO SS

iTrader: (77)

COngrats on finding the solution. Im having the same problems but my RPM tach dont work. Its giving out the crank, Tps, and a default for the cank sensor. A friend of mine came by with his tech 2 but no luck. Im talking it to an electrical specialist tuesday and hopfully find the problem. Enjoy your car

GreatWhiteHype01

Does anyone know how to do a crank sensor relearn without Tuning software? Does it require the software or a scan tool? I am having the same problem. The car backfires while I am driving down the road, cuts off, loses RPM signal altogether, backfires, cuts back on, it's horrible! I think I need to do a relearn and replace the wiring to it though. Thanks, any help is appreciated.

-Tom.

30th t/a

iTrader: (51)

a dealership can do it.

GreatWhiteHype01

Is there another way? My local dealer won't even let one of his tech's behind the wheel of my car....Once they saw the N20 solenoids they shut the hood and said that they cannot help me! This sucks.....any other way to relearn the crank sensor? Thanks. -Tom.

30th t/a

iTrader: (51)

make friends with someone that has the software or you can buy it yourself and learn how to do it.

ill tell you though, I know people that did a relearn and that didnt help at all. my buddy installed a new crank sensor and didnt do a relearn and his car is totally fine.

I would disconnect your crank sesnor wires and inspect them extrememly good from one end to the end where they go into the PCM

GreatWhiteHype01

I checked the dealership parts dept and they don't even show a pigtail for the crank sensor at all. Is this part of the main wiring harness? Does anyone know where to find a new wire and connector for the crank sensor? Thanks. -Tom.