what will happen if you dont disconnect the battery before welding exhaust???

[6bloodychunks]

ok, had my muffler delete done a few days ago.

but i didnt know i was supposed to disconnect the battery before welding on the car.

now the car is idling slightly higher than it was,and the rpm's climb slightly between shifts.

what could i have possibly screwed up by doing that?

HELP!!!

[6bloodychunks]

anyone?

[Russell James]

If it's still acting up after a few days of driving, I'd have someone with a scanner look at the data. Generally if something electronic got messed up, it would trigger the check engine light. So that's a good sign if no warning lights are on.

A scanner check by someone that knows what they are doing will show them if all the sensors are reading correctly. Such as the MAF, O2's, temp...

One DIY thing you could do is disconnect the battery for a few minutes. You will then have to reindex the windows (in the owner's manual). See if it normalizes after a couple of days of driving after the battery disconnect.

[JANNETTYRACING]

Originally Posted by 6bloodychunks

ok, had my muffler delete done a few days ago.

but i didnt know i was supposed to disconnect the battery before welding on the car.

now the car is idling slightly higher than it was,and the rpm's climb slightly between shifts.

what could i have possibly screwed up by doing that?

HELP!!!

Definately not related, I has been said that if you weld without disconnecting the battery it will Fry the computer and the car will not run.

I have been welding on cars without disconnecting battery for more than 25 years and never experienced a single problem.

Ted.

[6bloodychunks]

Originally Posted by Russell James

If it's still acting up after a few days of driving, I'd have someone with a scanner look at the data. Generally if something electronic got messed up, it would trigger the check engine light. So that's a good sign if no warning lights are on.

A scanner check by someone that knows what they are doing will show them if all the sensors are reading correctly. Such as the MAF, O2's, temp...

One DIY thing you could do is disconnect the battery for a few minutes. You will then have to reindex the windows (in the owner's manual). See if it normalizes after a couple of days of driving after the battery disconnect.

i will look into disconnecting the battery.

but what specificaly could it possibly have hurt by leaving the battery hooked up?

im worried that i hurt my baby.

[cab2g]

Originally Posted by 6bloodychunks

i will look into disconnecting the battery.

but what specificaly could it possibly have hurt by leaving the battery hooked up?

im worried that i hurt my baby.

From a logical standpoint the argument for harming your vehicle while welding with your battery plugged in doesn't have much ground to stand on.

First, since welding creates a lot of heat, if any damage was to be done it'd be from melted parts, this would happen whether or not the battery was plugged in.

Second, When the car is off, the battery is used to power devices in "sleep" mode. They are typically not performing any active operations, maybe the onstar module, but nothing else needs to be doing anything except storing memory.

Third, If you melted the battery while it was on, there is a very minimal possibility that could cause a power surge briefly, however, your car has a fuse box for a reason, if this surge occurred, any fuses with a current overload would be blown and your electronic components would be saved. I'd be more worried about the acid leaking out of the battery.

Forth, melting through your power cable somehow would in effect be the same as unplugging your battery. So if that's part of the argument, you can rest assured that severing a cable is the same thing as unplugging it from an electronic standpoint. The conductivity change due to heating the cable would be minimized by the length of the cable anyway.

[axis]

EVERY manufacturer says to disconnect the battery before you do damn near anything to your car. That's a standard response. Hell, several of the CAI instructions tell you to do that as well. The only thing electrical on a CAI is the MAF and it's unplugged. If welding on your car is going to mess it up, i'd highly doubt it would even run.

[6bloodychunks]

Originally Posted by cab2g

From a logical standpoint the argument for harming your vehicle while welding with your battery plugged in doesn't have much ground to stand on.

First, since welding creates a lot of heat, if any damage was to be done it'd be from melted parts, this would happen whether or not the battery was plugged in.

Second, When the car is off, the battery is used to power devices in "sleep" mode. They are typically not performing any active operations, maybe the onstar module, but nothing else needs to be doing anything except storing memory.

Third, If you melted the battery while it was on, there is a very minimal possibility that could cause a power surge briefly, however, your car has a fuse box for a reason, if this surge occurred, any fuses with a current overload would be blown and your electronic components would be saved. I'd be more worried about the acid leaking out of the battery.

Forth, melting through your power cable somehow would in effect be the same as unplugging your battery. So if that's part of the argument, you can rest assured that severing a cable is the same thing as unplugging it from an electronic standpoint. The conductivity change due to heating the cable would be minimized by the length of the cable anyway.

hmmm,so could the increased idle be attributed to the loss in back pressure from cutting the stock mufflers off??

i have only had the car a few days,and im worried i screwed something up.

[axis]

Originally Posted by 6bloodychunks

hmmm,so could the increased idle be attributed to the loss in back pressure from cutting the stock mufflers off??

i have only had the car a few days,and im worried i screwed something up.

There is very little, back pressure from the OEM mufflers. They are big and bulky but they are straight through. I highly doubt that's the culprit. Just how high is your idle? Have you done the fuse pull to reset the PCM?

[6bloodychunks]

Originally Posted by axis

There is very little, back pressure from the OEM mufflers. They are big and bulky but they are straight through. I highly doubt that's the culprit. Just how high is your idle? Have you done the fuse pull to reset the PCM?

it was originaly idling around 500rpm, now its idling around 700rom.

and when i push in the clutch to shift the rpms increase slightly,like its gassing itself slightly.

i did a fuse pull when i first got the car, but not since i had the mufflers deleted.

should i do the fuse pull again?

[Rage]

Just putting this out there..... You may be noticing your idle more now because you can actually hear your car at idle. I noticed what you are describing.... mostly when the engine is cold tho. Just my $.02

[IROCanSS]

Dude you're in PA, maybe it's getting cold out and the computer is telling the car to idle up a hair to comensate for the colder/dryer air. Not sure if that's it but it could be. Trust everyone. You're fine, it's 200 rpm. And do your self a favor, buy a real exhaust. You may think the delete sounds good, it doesn't hold a candle to an engineered exhaust.

[Russell James]

About the only thing the service manual says can cause a high idle is a vacuum leak, such as an open PCV vacuum line or EVAP vacuum line.

Did they open the hood at all?

I'd make sure there are no hoses off, such as the one going to the intake from the pcv line. Oil cap on tight.

Maybe they burned through one of the evap hoses in the back going to the tank. If they did the check engine light will be on soon. The EVAP system checks for vacuum leaks every drive the gas tank is between 10 and 90% full. After two drives, if there is a leak, it will turn on the check engine light.

If they didn't open the hood. My wild guess would be an evap vacuum line in the back is off. I'd take it back and ask them to put it up on a hoist and take a close look around the back where they were working. Find all the evap hoses back by the tank and make sure none got damaged.

[6bloodychunks]

its just driving me nuts,

and since it only did it after the muffler delete i figured that was the reason.

i know for sure that it didnt raise the rpm in between shifts until after i did the delete,

anything else it could be?