RPB

Hey Guys,

I know this topic has been discussed quite a bit in the past. I’d like to know if there is somewhat of a simple way to diagnose if the pump is faulty or not? My car has 67k, I am almost certain the pump is the original.

Cheers,

-Rob

KAMG

Lots of ways to test the pump:
1. Hook up STAR to activate it
2. Jump the relay in the trunk
3. Do multiple back to back pulls to see if it heat soaks
4. Use an OBDII bluetooth adapter with an app like Torque to see your IAT's, etc

tw2

I like the jump the pins in the trunk method. Link to instructions are in my signature.

RPB

Thx guys!

RPB

Thx! I’m intrigued by the OBD option w/ the capability, I only ever used one to diagnose codes.

I will definitely look into it.

Cheers.

drothgeb

I leave a jumper in the rear fuse box just for the occasion lol.

Exotic-metal55

If the pump looks stock, I would upgrade it for piece of mind anyway.

Bankroll

I did both recently. Recorded the intake temp, while making a couple of 3rd gear pulls. Drove normally, and did not see the IAT come down very much. 152° 1st pull, the 174° after 2nd pull. IAT stayed above 138° after easy driving with 50° ambient temp. Jumpered the relay at the rear sam, and did not hear pump. Verified by checking with a test light at the pump. Replaced with a Bosch 0392022010, for $99.98 from cascadegerman, (Ebay). Road test at 45° ambient. IAT was at 76° cruise, then 114° with a hard one gear pull, then qyickly back to 82°. All is good! By the way, my E55 has 128K well maintained miles, on original pump.

RPB

i plan on doing so! No brainer at this point.


Cheers.

kiluminati616

Is the issue with the stock pump that it doesn't flow enough coolant to the i/c which results in the fluid getting hotter than is optimal or is the pump usually completely dead...effectively turning our ic into a less effective air to air piece? just trying to better understand our engine.

I realized i had a bad pump after my car got heat soaked and lost all boost after a couple back to back pulls on the highway. Started the process to replace the ic pump in November but the vice grips my dad had were too stubby to cut the coolant hose off completely. is there a particular tool you guys use? i'm sure a couple needle nose vice grips would work but i'd rather not have to buy 2 pairs just for this one job.

planning to bleed the system with what i thought was the easiest process - briefly stomping on the gas. i've seen a few forum members mention that this will kick on the ic pump. I'm guessing you could do this with the stock piece to see if it's still working

KAMG

The stock pump will not keep up if you run the car hard; even a completely stock E55 can get heat soaked very quickly. That and the stock pump can die very early...I've seen low mileage cars with dead pumps. I discovered mine was dead after a about 2k miles and a few months of ownership at 87k miles. I drive like a grandpa most of the time and the previous owner was an older gentlemen so the pump could have been dead a while.

Vice grips are what most of us use. Pretty sure I used needle nose ones. Some say stomping on the gas works, some say it doesn't. Easiest way IMO is to jump the relay

tw2

With a dead pump, the IC acts as a heat sink which gets overloaded fairly quickly. It is then cooled by air entering the engine while off boost. The intercooler unit itself is insufficient to keep up but with a working pump it will heat soak a huge amount slower than with a broken pump. The recovery is very quick also. I have never had power cut from thermal overload.

tw2

Just for interest have a look at phase change fusion intercoolers http://www.autospeed.com/cms/article...ooler&A=110772
Aspects of it as similar to what you get with a broken pump.

RPB

A top notch explanation. Much appreciated!

trabots

Another way is to monitor your IC cooling water temp. If your pump is dead you will quickly see the temp climb, when all is OK the temp quickly starts to drop on start-up. The temp read sure lets you know what is going on with every brisk acceleration seen within seconds with a temp rise. Also after parking when hot and then starting up, the temp goes up depending on how long you were parked because the water in the IC itself has been heated by the hot engine. It quickly starts to drop again. As a guide I found that with a 2.5 gal tank of KC cooled water a full 1/4 mile run raised the temp of the water coming from the KC into the tank by nearly 30 deg F. I feel the same usefulness would be found with air/water heat exchangers, you could put the sensor anywhere between the H/E and the I/C.

RPB

I feel the best route is to replace the original pump. I’d go bonkers monitoring water temps..