deuce4935

iTrader: (2)

What the hell, at one point my ls1 caprice was running flawlessly. Now its backfiring and hesitating consistently and when I scanned it, it says bank 1 sensor 1 and 2 low voltage. Also, everytime I put gas in tank it overflows before the tank is anywhere near filled. I'm starting to think this swap was a mistake. Can anyone shed some light on these problems?

rotor vs. piston

iTrader: (3)

I would start at looking at your grounds and cleaning them and look for wires that may have shorted or corroded. Check/replace you O2 sensors after that, sounds like you kept the post cat' o2 sensor?


Gas over flowing just sounds like the rubber neck from where you put the gas into the car to the tank may be cracked or at the cheapest the clamps are worn out.

An LS swap is never a mistake. Don't let little issues get you down, new cars have issue.

zamora7

iTrader: (4)

I agree rotor vs. piston, bad 02 sensors will make your car run like complete crap. I can't really think of anything for your fuel tank issue. I'm currently working on a LS swap in my second gen T/A and can't wait til I fire it up.

deuce4935

iTrader: (2)

I did notice that my ground wire at the back of the head has began to unravel, its one of those laced type ground straps. I'll make some adjustments to it and check the remaining grounds, I just dont want to buy new O2 sensors and the problem still persist. i really would like to know what the low voltage message means.

Stu Cool

iTrader: (13)

For your fueling issue, make sure your vent tube from the tank is clear. If you are going into a charcoal canister with it, make sure the inlet to that is not blocked. As fuel goes into the tank, the displaced air needs a way out. Hang in there,

Pat

rotor vs. piston

iTrader: (3)

I've seen "low voltage" on sensors that just weren't connected at all, so it's either the wires are shorted, corroded, or just simply not making the connection.

deuce4935

iTrader: (2)

Doe's anyone know what the scan will read if the O2's need to be replaced? I guess I'm going to bite the bullet and buy new ones, as I just realized that it has been 2 years since I completed my swap, so maybe its time for them to be replaced.

flame

iTrader: (13)

Sounds like you have a fuel pressure issue. Check the fuel pressure at the rail. If fuel is good check the MAF. The chances of both O2's going bad at the same time are slim to none.

deuce4935

iTrader: (2)

Heres the latest. I had my vehicle scanned and the following codes were there, 102&103 maf low and high voltage. 121 tps performance. 131 bank 1 O2 sensor low voltage. 134 activity. 151 bank 1 sensor 2 low voltage. 153 bank 1 sensor 1 slow response. 154activity on bank 2 sensors. Im not sure why I'm getting activity on the bank 2 sensors when they are suppose to be turned off. I replaced the 02's with some from a running car and im still getting backfiring. Replaced tps with one from a running car, still backfiring. Someone had suggested unplugging the maf to see if the car will run better, I did that and theres a noticeable idle difference but once I opened the throttle up it began backfiring again. I checked that all coils were firing and they were. All the grounds are secured tight, and the plugs were replaced back in August. Could it be bad plug wires? If not that then I guess its time to get a gallon of premium and roast some marshmallows, because Im stupid as to what else could be problematic.

01cherryreds10

iTrader: (9)

What kind of tank and pump do you have?

deuce4935

iTrader: (2)

Which vehicle you referring to?

gofastwclass

iTrader: (2)

I had some really strange and intermittent drivability problems with my car last summer. After a day of head scratching and checking things, I discovered the top post battery the previous owner bought the day before I purchased the car had weak connections. Two new battery terminals later and all was happy.

Not saying it's your magic bullet, just another idea really.

Old Geezer

iTrader: (3)

Batt voltage is? Alt output is?

deuce4935

iTrader: (2)

With the car running and accessories on im getting between 12.4-13.6 volts.

Jimbo1367

isn't that a little low.......?

deuce4935

iTrader: (2)

Im not sure myself, perhaps someone who knows what the operating voltage should be will chime in.

bczee

iTrader: (12)

I think you would want at lease 13.8 to 14.5v... running. You might check your alternator out and that your Battery and its connects are good and clean.

Get your Battery load tested to see the health of it.

deuce4935

iTrader: (2)

Figured the problem was a bad plug wire on #8 cylinder. As for the voltage, Im thinking its time to swap out the Dakota Digital gauges, because when I scanned my car last week the scanner showed my temp at 220 while the gauge was showing 150. Also now the speedo isnt working and the tach is getting crazy. But at least theres no more backfiring.