Hello, the great people of Rennlist
Today I sadly got the dreaded (4266) Return pump fault on my modified 2003 996 Turbo X50, as many know the $$$price for a new one is ridiculous or just flat-out highway robbery ($5,353 from Sunset Porsche parts). Does anyone have any experience with these abs pumps? Does anyone know of rebuilders for the ABS pump or do I have to bite the bullet and buy a used one that will probably go bad again down the line? It seems that ABS pumps for 996 with AWD are starting to be a more common failure like the rear spoiler hydraulics. But, the only difference is I know of great shops that rebuild the spoiler hydraulics like cabriolet hydraulics in Sarasota, FL. I may even try taking the pump apart to see any failure points, I think the motor is what fails, and I may try to repair it. Luckily this is my weekend car, so I don't need to have it fixed asap, when I am not studying for my classes in college I will look at it with my dad. Luckily my daily driver Hyundai will never have an abs pump that costs that much . But if anyone has any input please let me know. THX P.S. I kinda need ABS and PCM since the car makes 600+hp.

 

Mine was leaking. I replaced it with a used one from Mazda RX7.

https://rennlist.com/forums/996-turb...placement.html

 

The return pump failure is probably a bad connection inside the ABS electronics module. I believe Module Masters can fix these Bosch 5.7 ABS modules. I thought these were a normal circuit board inside, but they are not. It's a ceramic hybrid module. It appears that excessive operation of the return pump melts internal wires.

Leaky hydraulics calls for a replacement ABS valve body, as Carlo_Carerra said find a used valve block with the same casting number, install your working electronics module (six torx screws) and you are in business. I have seen similar ABS modules in early 2000's Audis and BMW's.

 

According to the thread Carlos linked..using a thicker break fluid is recommended for these units. Is ATE Type 200 "thick" enough? I use this in my track car and was planning on using it in my TT when I bleed the brakes but if its going to cause issues down the road I'll use something else.

 

I don't think mine is leaking, I'll take a closer look next week. I will try cleaning the pins first, if it does not fix it, I will give module masters a call later this week about their 5.7 module repair service. Carlo Carrera, I find it pretty cool you used an abs valve body from a Mazda. I will try my best to keep the thread updated till I fix this problem. I can't thank you guys enough for your help, enjoy your easter.

 

A college student with a 600 HP X50 weekend car is not a problem.
Happy Easter

On second thought, there may be a problem, but it is not an ABS pump :-)

 

Mine was a nightmare. Started as a brake switch (replaced~4 times) fault. Had a number of folks try to help out (including Carlos). You can search for my threads. Tried just about everything (wiring, sent to UK, no fault found....) Eventually had to replace the ABS (tried the Mazda and it didn't work). Had at the mechanic for 6+ months. Eventually had to switch to dealership and paid a S*** load. Hope yours goes easier.

 

wross996tt sorry to hear that sounded like an extreme headache.

So yesterday I turned the abs light off with my piwis tester. I then moved the car at 3mph to run the pump and the light came immediately back on. So I parked it and cleared the code again. But, today I decided to drive the car a couple of times today and the light has now stayed off for 50 miles. My father speculates it was due to the car sitting for a month and not being driven, he says its more common to see the abs pump fail on 996s that sit a lot. so i am going to have a wait and see approach before i decide to mess with pump. So once a week i am going to drive the car down the drive way at 3mph to run the abs pump. Running the pump cleans armature/brushes inside and these armature/brushes possibly cause a high resistance that set the light on.

 

I'll just say that there light would go away after each brake switch change, but would eventually come back...I hope your doesn't.