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P0335 Crankshaft Position Sensor A Circuit Malfunction (L5)

25K views 16 replies 5 participants last post by  PPilon 
#1 ·
Does anyone have any tricks or tips so I can ensure this error code means what my mechanic thinks it means?

Here's the story:

My B started misbehaving in late July, starting laboriously and choking if I didn't give it some gas at start-up. The cruise control would disengage from time to time as well. Check Engine light was on. Ran my ODB scanner and it told me "P0335 Crankshaft Position Sensor A Circuit Malfunction (L5)".

My mechanic changed the CPS in late August (he had some trouble with it as it was fused to the enclosure.) The car ran great for 3 weeks. This week the Check Engine light came back, showing the same ODB code. I cleared the code but it came right back once I started the car.

Today the car is at my mechanic and he will change the CPS again (he's hoping its a faulty replacement CPS ). I had to change my starter last year, and the CPS this year, maybe twice now. And of course this morning, no Check Engine light, and it started like a charm. I read on here somewhere that the non-Bosch aftermarket CPS are crap. I'll ask my mechanic what he's using for parts.
 
#2 ·
So I had the CPS changed. Seemed to fix this... but... 1 year later... same problem. Had it changed again....worked for a while but 8 months later, same problem. It is frustrating that such an inexpensive part is so hard to replace and so unreliable... Hell, I would stock 2 at home and change them myself if I could.
 
#6 ·
It is a simple part and I think that it is far more likely that there is a wiring problem that is he root cause.
I noticed a puddle of water right besides the CPS and I'm thinking water vapor is causing the part to fail in 6-8 months. I mean the part failed in August 2014 and then a second CPS failed in February 2015. Now we are in July and if it was bad wiring I assume the problem would continue to plague me even after replacing the CPS. But it works for 6-8 months before failing...

Anyhoo. I decided to have a look on my own. I ordered the Bosch part (not an OEM, not a crappy knock off, a Bosch by Bosch CPS sensor). The part arrives tomorrow; I shall let you guys know how it goes! :nerd
 
#9 ·
Great photo PPilon..!!

With that oil filter cap showing on the left,..it's easy to pinpoint exactly where that photo is referring to. (thanks for the added orange boxes,... and/or maybe a small coolant leak..? )

Not exactly the easiest spot to see when looking down at the back of the firewall. I will also take a photo of that location on my B for the same reference purposes.

Thanks...
 
#10 ·
if im not mistaken, that is coolant hose

that coolant hose are from engine to the HVAC.

i blocked mine earlier this year because i dont want the coolant pass through the heater

i dont need that heater in our climate.

maybe the clipper loosen up already, u need to change that clipper i guess.

but the cost of changing it, u will need to topup your coolant.

that's my story. am i describing the real thing? i hope i get it right and help u abit.
 
#11 ·
i blocked mine earlier this year because i dont want the coolant pass through the heater

i dont need that heater in our climate.

.
How ...and more importantly,..why did you block a hose.?

If there is no flow through the heater,..I would think that the coolant might gel in time or cause heater core problems down the road.

If you don't need the heater,..then don't put it on ,..and naturally ,..just rely on your AC.
 
#13 ·
Thanks for that added info hafiez..

I would like to hear what others here think of this "mechanical play" with the coolant circulation. Could there be a heater valve problem..?

I do know that working down on those hoses would be a real PITA.


Here is a photo of my view when looking down there...and the similar view from page 1 with the added orange boxes..
Maybe not quite the same configuration in the 2 pics..?

It's certainly very busy down there..
 

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#14 ·
Thanks for that added info hafiez..

I would like to hear what others here think of this "mechanical play" with the coolant circulation. Could there be a heater valve problem..?

I do know that working down on those hoses would be a real PITA.


Here is a photo of my view when looking down there...and the similar view from page 1 with the added orange boxes..
Maybe not quite the same configuration in the 2 pics..?

It's certainly very busy down there..
Hey DEVOURS,
Looks like the same config, just different angles. In order to match the 2 pics, you need to move over about 4 inches to the right and take a pic looking straight down over the valve covers. That braided patch on your pic is the s-curved hose on the other pic. He's looking straight down the metal pipes, and you're coming in left of the pipe and that's why your pic doesn't show the sensor. But it looks pretty much the same.
 
#16 ·
CPS Troubles

Hi guys;

I haven't had a chance to change the part yet - wifey took the week off to go see her parents and I'm here all alone with my bicycle and bus pass haha :).
I'll take care of it next week most probably, and will let you know how it went.
 
#17 ·
CPS Troubles - over... (I hope!)

Alright! I am officially an incompetent car mechanic. Unable to swap it on my own. Way too deep and tight for my big hands.

My local garage did it for 40$. they had to lift it up to get to the CPS. Car now runs like new. Thing is, it ran like new for 6 months the other two times... Oh well. We drove it for hours in traffic and highway during a couple of very hot days and it starts absolutely flawlessly, and never even gives a hiccup or sign of stalling at stop lights or anything like the previously described symptoms.

Thanks to everybody for the help, and good luck to all B owners!
 
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