Technical Dreaded P0335 Crank Sensor fault code

[DaveMcT]

The 40AH battery on my 100HP is more than enough. None of them last for ever so just fit a new cheap one.

Saying that, I fitted a 54AH Yuasa HSB012 to my wife's car.
Tanya Batteries £59.00 incl next day delivery. Or you could pay £103.00 at Halfords.

I had a 4AH LiFePO4 (LFP) battery on the bike. It had the same usable starting power as the 14AH lead I acid previously on the bike. I tried it on the 100HP and everything worked fine including heated window lights and power steering going lock to lock.

I chickened out for putting one on the car, but I think it would have been fine. Leads acids have a high AH number because they can only deliver 30% at full current and they degrade over time so bigger capacity means longer working life.

 

[koalar]

I have mention this a few times before but worth remembering.

battery Ah is a meaningless number. Different manufacturers test to there own

its not a standard. By changing the test parameters the same battery could be 40Ah, 50Ah.

CCA is a standardised test.


Fairly sure but not 100%

one of my cars had an original small cube battery last 12 years by its date code.

 

[rmjbn1]

Fixed!

New crankshaft sensor and she's starting and running fine again.

Old sensor has lost a lot of its magnetism (heh, it's not the only one...) New sensor kept trying to stick itself to the pulley when putting it on, the magnet is much stronger.

Just 70 Euro poorer this time, 40EUR for the sensor (Magneti Marelli, same as the old one), 30EUR to diagnose P0335, fit new sensor & clear codes.

Wiring checked, battery voltage was holding fine, alternator checked out fine. Running extra earth and connecting to different battery made no difference. I'll still replace the battery, earth strap and plug leads anyway as they're pretty old, and a power steering fault code kept coming back.

Would like to have done it myself, but couldn't get my cheapo OBD2 interface to speak to any software, and I doubt I could have got the part delivered any cheaper anyway.

Thanks all for your help

 

[rmjbn1]

Thought I'd just add something about my experience of getting this fault diagnosed:

Ended up taking the car to two different local independent garages.

First place charged 30 Euro to carry out a health check scan. Loads of old codes came up: power steering, airbag, abs, alternator etc. Codes cleared but most came back.

He thought it was stalling as the fuel pump was not getting power, probably fault in ECU due to all the error codes being thrown up.

He couldn't or wouldn't give any specific fault codes, diagnosis was to get a new ECU as the old one's 'having a stroke'.

Bumped into second chap in his van when stalled at a junction trying to get home! He thought that diagnosis was rubbish, had a code reader with him, quickly pulled up P0335.

He doesn't charge for scanning for fault codes, was happy to check over the wiring, battery, earth & alternator with me, and could get a new sensor added to his scheduled delivery next morning for considerably cheaper than I could have got it (free delivery isn't really a thing in Ireland).

Goes to show that even the professionals' equipment is only as good as the person using it I guess.

 

[Yolanda]

Fixed!

New crankshaft sensor and she's starting and running fine again.

Old sensor has lost a lot of its magnetism (heh, it's not the only one...) New sensor kept trying to stick itself to the pulley when putting it on, the magnet is much stronger.

Just 70 Euro poorer this time, 40EUR for the sensor (Magneti Marelli, same as the old one), 30EUR to diagnose P0335, fit new sensor & clear codes.

Wiring checked, battery voltage was holding fine, alternator checked out fine. Running extra earth and connecting to different battery made no difference. I'll still replace the battery, earth strap and plug leads anyway as they're pretty old, and a power steering fault code kept coming back.

Would like to have done it myself, but couldn't get my cheapo OBD2 interface to speak to any software, and I doubt I could have got the part delivered any cheaper anyway.

Thanks all for your help

I wonder if it's the crankshaft position sensor that's on it's way out on my 2004 1200 8 valve. when accelerating from low speed and low revs the engine shudders/ cuts out a couple of times for a split second till the revs pick up. It doesn't do it till the engine is at normal running temp and it doesn't do it at higher revs. I've cleaned the MAF sensor and all battery connections to no avail. I have cleaned the throttle body some months ago but it's only started doing this a few weeks ago, there are also no codes.
Help required please.

 

[koalar]

Sounds more like hesitation due to a misfire to me

Doesn’t sound like the crank sensor. If the car starts a crank sensor will normally not rev past a certain point or cut out completely when hot

 

[koalar]

Shame it’s not throwing up a code

Both the coils and plugs will give a similar symptoms

As will low compression and loads of other things

Do you have a compression tester
Do you have a scan tool that can read the data from the sensors

If when warmed up and the fault is present

If you select neutral will it rev freely to 4,000 rpm if it does you can almost rule out the crank sensor

 

[The Panda Nut]

Our 2004 1.2 has just been diagnosed with fault code P0335 rpm sensor. Car has cable throttle and camshaft position sensor as well as crankshaft sensor.

Had it checked for codes after intermittent sudden stalling. Most frequently when slowing down or off throttle, but has happened at speed with engine hot too.

No misfire or rough running, engine abruptly stalls. Sometimes engine cuts back in and continues to run fine, sometimes car coasts to a halt.

Sometimes engine will turn over without firing from hot or cold, sometimes starts and runs normally.

Following above advice, I was planning to:

• charge the battery
• run a temporary earth with a jump lead from battery negative to gearbox
• check the timing belt hasn't slipped
• check the alternator is charging and not sticking / slipping belt
• check cylinder compression to confirm head gasket is OK
• test again

Is there anything else I should consider before replacing the crankshaft sensor, please?

Coils?

 

[Yolanda]

Thanks for the replies. I did a live data check with a scan tool and it looked like the sensors although I don't know which ones were ok as at the bottom of each readout it said Pass. To me though I could be wrong, it doesn't feel like a single misfire more like a complete engine stall but only for as I say a split second and why does it only do it when at normal running temp. Can the coils be tested if so how.
Thanks.

 

[koalar]

On your engine 1 coil does 2 cylinders if it’s regularly misfiring due to the coil you should see 2 spark plugs are different


Post a picture of all spark plugs in a line

 

[rmjbn1]

My symptoms of a failing crank sensor were, in order:
1. Wouldn't fire when warm
2. Cut out for 1-2 seconds whilst driving when warm, under acceleration from low speed. Clearly wasn't a misfire, engine died completely, revs dropped to 0
3. Would occasionally cut out or refuse to fire, engine warm or cold. Became more frequent.

Rest of the time, the car ran with no issues. It was usually fine, then dead, then fine again.
I don't remember the car struggling to rev at all. I took to heel & toeing to keep the revs high when braking to try and stop it cutting out (it didn't help).

From your symptoms it sounds possible it could be crank sensor, but without code P0335 to back it up, could be a number of other things.

Crank position sensor is cheap, one bolt to replace, and I suspect it's possible they deteriorate over time (as the magnet was so much stronger in the new sensor), so I'd argue there's not much to lose by replacing it.

 

[koalar]

My symptoms of a failing crank sensor were, in order:
1. Wouldn't fire when warm
2. Cut out for 1-2 seconds whilst driving when warm, under acceleration from low speed. Clearly wasn't a misfire, engine died completely, revs dropped to 0
3. Would occasionally cut out or refuse to fire, engine warm or cold. Became more frequent.

Rest of the time, the car ran with no issues. It was usually fine, then nothing.
I don't remember the car struggling to rev at all. I took to heel & toeing to keep the revs high when braking to try and stop it cutting out (it didn't help).

From your symptoms it sounds possible it could be crank sensor, but without code P0335 to back it up, could be a number of other things.

Crank position sensor is cheap, one bolt to replace, and I suspect it's possible they deteriorate over time (as the magnet was so much stronger in the new sensor), so I'd argue there's not much to lose by replacing it.

The thread is confusing as there are different people with different symptoms

Yours behaved as most do

Cutting out
Not staring
Heat related

Heating up the sensors with a hair dryer would have confirmed it

Does matter now as it now fixed

@Yolanda has a hesitation on acceleration which in my opinion is unlikely to be a crank sensor and sounds more like a misfire which has many causes

Probably would be better in a new thread

 

[Yolanda]

On your engine 1 coil does 2 cylinders if it’s regularly misfiring due to the coil you should see 2 spark plugs are different
e

Post a picture of all spark plugs in a line

I removed the plugs the other week whilst doing the annual service they all looked fine ie a light sandy colour.
As I said it only seems to do the rapid cutting out when accelerating from low revs when hot. It's puzzling not having any codes to work from.
I suppose I could go down the elimination rout coils, leads, plugs etc but then it could also be a wiring problem.

 

[koalar]

I removed the plugs the other week whilst doing the annual service they all looked fine ie a light sandy colour.
As I said it only seems to do the rapid cutting out when accelerating from low revs when hot. It's puzzling not having any codes to work from.
I suppose I could go down the elimination rout coils, leads, plugs etc but then it could also be a wiring problem.

Not unusual to not get an error code

Nice when it does as it give you a starting place

I ran a car with very little compression in cylinders 1 and 2 at low revs it was only firing 3 cylinder. Fuel trims were maxed out but it never gave a code

Post a picture of the spark plugs. Are you UK based. Do you use Super unleaded. Nowadays the spark plugs go dark grey unlike the days of leaded petrol

 

[Yolanda]

I'm in Stockport. I'm going to do a bit more investigating today, plug leads etc.

 

[koalar]

I'm in Stockport. I'm going to do a bit more investigating today, plug leads etc.

I am not far away near Crewe

Look at the pre cat O2 sensor voltage

Hot engine

At idle let it rest for a few minutes

Then raise and hold the revs at around 3000 rpm

If your scanner can read fuel trims it useful to see what happening

 

[koalar]

I properly have a spare coil and MAP sensor you can try

There not here and will have to check they haven’t been chucked away by the other half

 

[Yolanda]

Today.
Removed Plug leads for external inspection.
Coil packs removed cleaned and inspected for cracks etc.
Removed all electrical connectors from throttle body cleaned and replaced.
Removed and cleaned engine breather pipe from top cover to throttle body
Cam and crank sensors removed and cleaned ( yesterday )
Took car for a run to get engine nice and hot and the fault didn't show. However when I got about half a mile from home the fault came back, but not as severe so back to square one.
My scanner does show fuel trims etc but it's something I've not had any experience with in the past so I'm a bit lost there.
You mention the MAP sensor where about is that situated on the engine. I had the throttle body off a few months ago for a general clean up but I didn't notice it near there.

 

[koalar]

front left of the black plastic inlet manifold

You don’t have to remove the air box


One TX screw

 

[koalar]

Same as this

500 (2007+) - How to clean/replace Fiat 500 1.2 MAP-sensor

This thread is for the general discussion of the Guide How to clean/replace Fiat 500 1.2 MAP-sensor. Please add to the discussion here. 500F submitted a new guide: How to clean/replace Fiat 500 1.2 MAP-sensor MAP-sensor measures the amount of air in a inlet manifold and also air temperature...

www.fiatforum.com

Don’t turn it upside down to clean. The electronics at the end aren’t sealed from the sensor tip


Normally they give bad readings if there is a dip of oil on the end