325i push button start switch

[moms now.mine]

Hi.

It's been a while. Now back to diagnosing more problems with this E90 06 325i base model.

Car now is stuck in what seems to be 3rd gear. I am an adventurous driver and late night omw home can press the pedal. At 110mph the engine power just slipped and wound out. I could not accelerate and had to pull off highway. I turned off car, let it sit for 20 min and car then stayed in what I think is 3rd gear. Now at 4000 rpm I'm doing 50mph.  Could be a bad solenoid?  If it is, will a new  solenoid kit be correct diagnosis? I hate to consider a BMW dealership mechanic for repair but I want some input if I am correct. 

I am at wits end in maintenance  getting this BMW up to my expectations.

Tires, transmission repair, or internal engine repair is where I draw line and seek a professional to make proper repair. And advise helps.

Replaces to date,

New entire Headlights(2)  brakes,rotors,caliper,alternator,battery,radiator hoses, belt tensioner, belt, 4 pirelli run flats,rear shocks, front full struts. . All done myself except tires. About 20hr labor. 

Another $400 is all I'm kicking out. Only 90k miles and inherited with 75k miles. 

Any advice?

[Greydog]

Morning Christopher

Oh dear !! Sounds like Trans Fail Safe has been triggered

Causes could be Low Trans Fluid could be a Solenoid sticking could Torque converter related could be a Mechatronics unit issue

ZF who make the transmission in your car recommend service at 60 to 100k so due by your mileage. 

Find a good Trans Specialist they should be able to scan the box update the software and service it (just make sure they use the correct ZF Longlife Fluid

As a comparison my E53 4.6is with Dinan cams and throttle body (400 + hp) is on 164k it gets a hard life when it's driven and is smooth even under hard acceleration but has been serviced (last one flush as well)

Dave

[moms now.mine]

On 2/17/2024 at 2:35 AM, Greydog said:

Morning 

If a fuse is blown there is no power flowing so it follows that the unit controlled by that fuse should be dead not drawing power. As your stop start switch is power on a couple of thoughts has the switch been changed? there are a number of interlocks connected to the stop/start switch. There is a Brake switch and a Gear sector switch either of these could be at fault or the loom between

So while your checking

Good Hunting

 

Hi.

That start/stop ignition button never turns off. Same with the P when parked. I will check the mini fuses on the car. I even added some not in fuse box. I will look for gear and brake fuse. On diagram and #.

Thanks