Idling issue after disconnecting battery

[RedHoodRidah]

I take my car battery out to clean up all the mold and water under it. When i reconnect it and turn on the car, the cars rpm's go from a good 400 to about 200 then it dies after 2 seconds of being in the 200 range. Also my car now has the oil service light lit in red and is asking for engine oil. It hasnt been 3 weeks since i changed the oil so i dont know why it is asking for oil service and engine oil. The car is an 87 325is 5 speed.

[arsevader]

I take my car battery out to clean up all the mold and water under it. When i reconnect it and turn on the car, the cars rpm's go from a good 400 to about 200 then it dies after 2 seconds of being in the 200 range. Also my car now has the oil service light lit in red and is asking for engine oil. It hasnt been 3 weeks since i changed the oil so i dont know why it is asking for oil service and engine oil. The car is an 87 325is 5 speed.

When you disconnected the battery, you wiped the computer's memory. It just takes a few starts and restarts to remap the adaption tables back into the computer.

[RedHoodRidah]

When you disconnected the battery, you wiped the computer's memory. It just takes a few starts and restarts to remap the adaption tables back into the computer.

Thanks man.

[RedHoodRidah]

I just started it up a few times and it keeps turning off. I reved it up to an 1k rpms and took it for a spin around the block and at every stop sign it just kept turning off. When i let it sit for a good 10 minutes or so and turn it back on the rpms stay at around 800-900 and idles a bit. WHen i turn it off and try to turn it on again it just keep dying after. I noticed that when the ignition is on i get this weird buzzing noise from the intake. Can anyone help me out?

[arsevader]

I just started it up a few times and it keeps turning off. I reved it up to an 1k rpms and took it for a spin around the block and at every stop sign it just kept turning off. When i let it sit for a good 10 minutes or so and turn it back on the rpms stay at around 800-900 and idles a bit. WHen i turn it off and try to turn it on again it just keep dying after. I noticed that when the ignition is on i get this weird buzzing noise from the intake. Can anyone help me out?

Hmm did you disconnect anything else?

1) The buzzing is the jsut idle control valve. You can hear it when the ignition is on but the engine is off

2) Check your battery voltage

3) Did you hook the battery up securely?

[RedHoodRidah]

Hmm did you disconnect anything else?

1) The buzzing is the jsut idle control valve. You can hear it when the ignition is on but the engine is off

2) Check your battery voltage

3) Did you hook the battery up securely?

The battery is hooked up tight and secure. The battery is giving the whole car full power.

[RedHoodRidah]

Anyone? I really need the help.

[Branan]

Ecu?

Anyone? I really need the help.

Apparently someone has developed a theory that the ecu's fail in stages, ie they exhibit an increasing number of symptoms. I know I know, computers are binaryand they typically have catastrophic failures, but this type of behaviour can happen.

Does your 5 pedla press diagnostic work?

I mention this because I have high fuel consumption and rich mixture. Yes all ICV, TPS, temps sens's etc have been tested/replaced/cleaned etc. and there is no other diagnostic I can think of. Furhter the 5 pedal pump diagnostic nets no results.
Apparently diagnostic failure (attributed to ecu failure) in 88 325is is common. What's your production year?

Just an option to investigate

[RedHoodRidah]

Apparently someone has developed a theory that the ecu's fail in stages, ie they exhibit an increasing number of symptoms. I know I know, computers are binaryand they typically have catastrophic failures, but this type of behaviour can happen.

Does your 5 pedla press diagnostic work?

I mention this because I have high fuel consumption and rich mixture. Yes all ICV, TPS, temps sens's etc have been tested/replaced/cleaned etc. and there is no other diagnostic I can think of. Furhter the 5 pedal pump diagnostic nets no results.
Apparently diagnostic failure (attributed to ecu failure) in 88 325is is common. What's your production year?

Just an option to investigate

Its an 87 325is. I tried the 5 pedal press and nothing. The car seems as if something is not giving it power to push all the way so it stumbles. Should i get the battery charged all the way at autozone or something?

[RedHoodRidah]

Bump

[RedHoodRidah]

SOmeone help. I need the car for school tomorrow.

[RobertK]

If you've never swapped out the ECU then I believe the 87 iS came with the 153 ECU which is notorious for fucking up. I would suggest replacing it with a 173 ECU.

As a matter of fact I think MR 325 has one for sale in the "For Sale" forums for $65 shipped. I would jump on that if I were you.

[RedHoodRidah]

If you've never swapped out the ECU then I believe the 87 iS came with the 153 ECU which is notorious for fucking up. I would suggest replacing it with a 173 ECU.

As a matter of fact I think MR 325 has one for sale in the "For Sale" forums for $65 shipped. I would jump on that if I were you.

Thanks. The car is now starting to throw out white smoke and is riding even worst. The check engine light keeps coming on and off. All this just because of taking out a battery.

[arsevader]

Thanks. The car is now starting to throw out white smoke and is riding even worst. The check engine light keeps coming on and off. All this just because of taking out a battery.

White smoke ain't from a disconnected battery.

It's either moisture (which would go away eventually) or you've got a coolant leak (blown head gasket, or a cracked head/block).

[Branan]

Follow-up - Any luck?

I swapped out my ecu and chip and my car still does the same thing, does yours?

to fix this problem you are having, have you tried re-disconnecting the battery and letting the ecu reset?

Branan