connected battery backwards

[m2rtin]

Hi, I connected battery backwards on my Chevy Impala SS 1996. Shortly after that I disconected it, It smoked from alternator, but it was OK, The engine is running but it is rich as hell. Idle and high RPM is somehow ok, but bewen there is a gap where it has no performance. Anyone knows what could be wrong?

Thanks for any advice!

[jiveass]

hmm..is the service engine light on? if so have it checked out..could have screwed somethin up in the alternator....i know lack of voltage can really effect performance...otherwise drive it around for a while and see if it clears up.

[shady milkman]

more than likely you fried the alt. and a few sensors .....if the alt is flaky it will effect the sensors readings and such.

[m2rtin]

alternator seems to be all right, no check engine light and diagnostics didn't recognise any bad sensors. When it runs it is all insane. Speed 180km/h, temperature -68°C and so on. But the scan can't find any errors.

[shady milkman]

alternator seems to be all right, no check engine light and diagnostics didn't recognise any bad sensors. When it runs it is all insane. Speed 180km/h, temperature -68°C and so on. But the scan can't find any errors.

odbI is not very sensitive when it comes to that.........like i said .....get a new alt. and it should fix it.

[0rion]

I've never ran into any of this before but I would probably try to pull the batt. and pcm fuses and let it sit for a few minutes and see what that does.

[Smittro]

Power chip is cooked. Replace the ECM, your current one is prolly in limp mode. Changing the chip may help but most likely the FET's took the hit and are cooked now though. Best to replace the whole unit..imho

[m2rtin]

OK, the alternator is cooked, anyone know where to find a bridge rectifier for less then 100 bucks?

[m2rtin]

The ECM was OK, You know what wasn't? the water temperature sensor. When removed, it started to act like a car!

[jiveass]

The ECM was OK, You know what wasn't? the water temperature sensor. When removed, it started to act like a car!

thats some crazyness...although i do recall my 83 eldorado runnin like crap when the coolant temp sensor was out.....just wonderin how your battery fried that sensor.

[Smittro]

thats some crazyness...although i do recall my 83 eldorado runnin like crap when the coolant temp sensor was out.....just wonderin how your battery fried that sensor.

+2, curious...

[KMdef9]

+2, curious...

+3. Just like you Smittro, I was thinking the ECU would be fried from back feeding... well... everything.

Bridge rectifier for the voltage regulator? I know you can buy them all over the place, I but think you have to replace the whole regulator? Or the alternator is good now?

[m2rtin]

You know the car was sitting in a barn for a few years, so there is a way, that the coolant temp sensor was done already before the polarity mistake. And it took a few seconds, I acted quickly when alternator smoked. But yeah, I believe the diode trio is cooked and that's what need. But You see, I'm from Europe and there is no such thing as a hevy duty 140 amp alternator :s...We don't have these lying around...So I need some decent store with alt. parts or something...

[jiveass]

You know the car was sitting in a barn for a few years, so there is a way, that the coolant temp sensor was done already before the polarity mistake. And it took a few seconds, I acted quickly when alternator smoked. But yeah, I believe the diode trio is cooked and that's what need. But You see, I'm from Europe and there is no such thing as a hevy duty 140 amp alternator :s...We don't have these lying around...So I need some decent store with alt. parts or something...

online shopping is the best way to go.....

[m2rtin]

online shopping is the best way to go.....

Yeah, but alternatorparts is not willing to do bussiness, rockauto does have a good manners but bad price for rectifiers, it is better to buy new alternator. But that's hundred for the alternator and hundred for the shipping. And that's the base for duties.

Do You think that 96' impala ss does need 140 amp hevy duty alternator? I mean shouldn't 75amp be sufficient enough?

[Orcus79]

I believe the SS cars came with the police/taxi package. Generally those packages come with a heavy duty high amp alternator to cover the added load like lights and radios and so forth.

75amp should be fine, though for me what comes out is what goes in parts wise.

[cammed goat]

I believe the SS cars came with the police/taxi package. Generally those packages come with a heavy duty high amp alternator to cover the added load like lights and radios and so forth.

75amp should be fine, though for me what comes out is what goes in parts wise.

^^This.

[Smittro]

Yeah, but alternatorparts is not willing to do bussiness, rockauto does have a good manners but bad price for rectifiers, it is better to buy new alternator. But that's hundred for the alternator and hundred for the shipping. And that's the base for duties.

Do You think that 96' impala ss does need 140 amp hevy duty alternator? I mean shouldn't 75amp be sufficient enough?

100 for shipping!?!? where ya live the moon? lol that's crazy you should be able to get a new setup shipped to your door for far less.. wow I've have egay metal suppliers that ship in weights far higher than an alt. that don't charge 100 bucks for heavy metal stock.. Keep lookin' bro..

[shady milkman]

100 for shipping!?!? where ya live the moon? lol that's crazy you should be able to get a new setup shipped to your door for far less.. wow I've have egay metal suppliers that ship in weights far higher than an alt. that don't charge 100 bucks for heavy metal stock.. Keep lookin' bro..

he lives in the czech ...that may have something to do with it

[Smittro]

he lives in the czech ...that may have something to do with it

I have relatives working for Westing House and have lived everywhere from the czech rep. (Prague), to china and so forth.. Tho the czech republic is not here they still have acsess to good shipping rates .. I'd keep looking..