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Old 12-05-2012, 02:40 AM
MySatinDoll MySatinDoll is offline
I'm from NJ. So What!?!
Location: Near "The Situation" sadly :(
Join Date: Jan 2011
Posts: 2,232
Mein Auto: What they Drive
just my .02
Was all of this occuring prior to you doing anything to the car?
I ask for if it wasn't, then you're going to have to back track what you done.
which sucks.

However If you performed all the necessary or better said common issues with your m30b35.
Then you should begin to look at your electricals namely your sensors for you cooling system.
People tend to forget about them and change out everything else.
There are four:

- rightside of the radiator (associated with your aux fan and less likely)
- black sensor on thermostat housing (possible)
- blue sensor on thermostat housing (possible)
- one on the expansion tank (not likely)

The blue and black sensors deal with your temp gauge.
One goes before the other. Sorry I forgot which kicks the bucket first.
To be safe replace both. You can buy them new or hit a junkyard for them.
The one on the radiator does as well but that's more of a aux fan control.

The one in your expansion tank deals with your coolant level.
Not really related unless it's not reading on the dash and you open the expansion tank only to see no coolant or it gushing out.
Another junkyard gem to pick up. If you get one from a junkyard get the connector too. That socket likes to crumble with age.

Your aux fan probably needs a resistor bypass or again a new sensor.
If the end of the sensor can move. Or the male connection is f'd up (another that crumbles with age).
Probably time for a new one.
The resistor bypass is a common issue. (the small black wired brick on the side of your aux fan frame) just eliminate it by splicing around it.
Doesn't hurt the car.

What type temp grad is you're thermostat?
There are 2. I use the higher temp thermostat

Have you checked all your coolant hoses? Were there any pin hole leaks?
These type of leaks no matter how minor can throw the cooling system off.
Look for white hazy stains or wet marks along the radiator, thermostat, lower part of the engine block, on the or around expansion tank.
Especially check your floor board behind the passenger seat. The heat core drain falls back there. If it's damp. You found your leak.

Check your vaccum hoses. Just throwin that one out there.

Y U JB Weld your radiator?!?
Hit the junkyard and pick one up for a little more than what you paid for JBweld.

Like robert stated it could be many different factors.
Being we're talking about a M30. 9/10 the issues are not that bad.
Just a factor of hunting them down and knocking them off one by one.

It can be time consuming. But nothing a novice with a bentley and minor tools can't pull off.

Also you have to remember these cars are not spring chickens.
Unless you pick up a cherry e34. You're going to have to pull out the debit or credit card for a few things.

Good luck

Last edited by MySatinDoll; 12-05-2012 at 02:49 AM.
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