Mike96z

iTrader: (78)

agee'd, just wanna take the small stuff out before I pull the front cover. Personally think its the timing chain/set. But I wanna get the rest out of the way and flash it back to stock to see if that helps.

Mike96z

iTrader: (78)

replaced the faulty stock wires with MSD 8.5mm wires and i fired it up, didnt pop, could still hear it hesitate a little but I will test it for real tommorow, try to drive it and see what it does under load. I did get some smoke from the cylinder that had the bad wire and that says to me it wasnt even firing because i coated the headers and when you start a car for the first time after coating them they smoke a little. Well it was smoking from that cylinder. I still have a little work to do and well see how everything goes.

Mike96z

iTrader: (78)

im going to check the timing chain. but i put MSd wires and after watching my vid again i just noticed only the passenger side is throwing flames........... and 6 & 8 had bad plug wires but it is still popping. What could I check for ...... may just be that side only.

BadCompany VP WS6

iTrader: (6)

Cam sensor or crank sensor.

Try those.

Mike96z

iTrader: (78)

they have new plugs, ima check them out today, i ordered a double roller cc kit just in case. im leaning towards maybe a bad coil on 6 & 8. Cant believe i just noticed the fire only on one side. Ill test crank and cam sensor but i think if its throwing flames on one side then its gotta be something specific. I already know its not the o2's like suspected and I have Y-Pipe now and the vid is old. Thanks

Mike96z

iTrader: (78)

Update. I replaced the coils but that didnt solve anything so sold the ones I bought for it. I put new plugs and new wires. I also checked the timing chain and all lines up. Still backfiring some and when I drive it, it seems like it doesnt wanna climb RPM's, like it struggles to do so. Well finally drove it about 1 or 2 blocks to the nearest autozone to get the codes read and here is what I found.

P0342 Camshaft Position Sensor Low Voltage
P0452 Fuel Tank Pressure Sensor Low Voltage

2 other codes were present but are EGR and egr is being deleted. P0443/P0449

As far as the first two codes go, Im going to replace the Camshaft position sensor, thinking its the main problem. Not sure what the fuel tank pressure sensor has to do with anything and I think it should run fine without it correct?

I'm still going to check fuel pressure and compression in each cylinder and hopefully the cam sensor fixes it. If I have good fuel pressure and still have a bad fuel tank pressure sensor, should I replace it?

If all fails, heads are coming off and Im checking for bad valves.



Let me know what you guys think.

ramairracer

iTrader: (13)

heres the decription of the cam sensor it looks like the pcm is confused on what stroke themotors on thats why its backfiring! the FTP sensor is for evap purposes only and would probably not make it run bad.. id put a cam sensor and go from there...
Circuit Description
The Camshaft Position sensor is mounted through the top of the engine block at the rear of the valley cover. The CMP sensor works in conjunction with a 1X reluctor wheel on the camshaft. The reluctor wheel is inside the engine immediately in front of the rear cam bearing. The PCM provides a 12 volt power supply to the CMP sensor as well as a ground and a signal circuit.

The CMP sensor determines whether a cylinder is on a firing stroke or on an exhaust stroke. As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads. The PCM uses this 1X signal in combination with the Crankshaft Position sensor 24X signal in order to determine crankshaft position and stroke. This diagnostic for the Camshaft Position sensor tests for a loss of Camshaft Position sensor signal.

Observe that as long as the Crankshaft Position sensor 24X signal is available, the engine will start. The PCM can determine top dead center for all cylinders by using the Crankshaft Position sensor 24X signal alone. The Camshaft Position sensor 1X signal is used by the PCM to determine if the cylinder at top dead center is on the firing stroke, or the exhaust stroke. The system attempts synchronization and looks for an increase in engine speed indicating the engine started. If the PCM does not detect an increase in engine speed, the PCM incorrectly synchronized to the exhaust stroke and will re-sync to the opposite cam position. A slightly longer cranking time may be a symptom of this condition.

Mike96z

iTrader: (78)

Thanks for the info, picked up a sensor and Ill see what this does.

BadCompany VP WS6

iTrader: (6)

I accept Cash only. Thanks.

Mike96z

iTrader: (78)

lol

Mike96z

iTrader: (78)

Umm. yea I found out that the cam sensor wasnt even plugged in. I hooked it up. The plug is what I believe went there. It was coming from the passenger side and was a very long wire that was separated with wire protector and had a 3 prong connector and I hooked it up but still popped and idles irregular. Im going to drive it around awhile and see if something changes. It does start up faster and should climb rpms quicker.

Mike96z

iTrader: (78)

The map sensor was plugged up.

Mike96z

iTrader: (78)

Had a fellow member come over with his HPTuners and try to reflash it with a stock tune. The car took the tune but it would not start nor run with a stock tune. So I had to keep the tune that was in the car. The tune had been modified from what we saw, the max rpm, max mph, and octane tables have all been touched. Nothing we tried worked except for the tune that was in the PCM which was not stock. So we ended up taking the tune that would start/run and removing the EGR/CAT codes and other codes that I did not need showing up, as well as turning misfires off.

So tuning the computer didnt work and it wouldnt take a stock tune which is wierd so the next move is to check fuel pressure, compression and then pulling the heads and checking for bent/burnt valves. The car is obviously missing at idle, the two guys I had looking at it noticed it immediately, also said there was alot of valvetrain noise.

TXjeepTJ

iTrader: (8)

my MAF was going out and caused my ls1 to backfire randomly, once i unplugged it, the backfiring stopped(didnt run it like that though, got a new MAF)

Mike96z

iTrader: (78)

Did yours throw a code? Mine isnt throwing a code and from experience, when the MAF goes bad, it wants to bog down and when you start it, it will want to die.

TXjeepTJ

iTrader: (8)

nope mine didnt throw a code, the sensor was dirty soo it would cause it to randomly give bad signals to the pcm

Mike96z

iTrader: (78)

Mine isnt that old and I was running it on another engine before for not too long and it is ported.

Mike96z

iTrader: (78)

compression test numbers

Alright, here are the numbers, Im thinking I have a burnt valve or bent push rod or something maybe bent valve, it pops and backfires, alot of valvetrane noise on the passenger side. Not sure what compression should be but here it is.

#1 210
#3 220
#5 200
#7 210

#2 210
#4 180
#6 180
#8 (didnt do it, too hard, tried for an hour) guessing its around 200)

Let me know what anyone thinks of this. Help is appreciated.