fault code 34 and 47 ? mil light strange running ? help

[niks_terrano ii]

hi guys,

last weekend my mil light came on for the 1st time since ive owned the truck.
i was just out driving normally and it just flicked on then stayed on for maybe a few seconds then went off again then after a few mins came on again then flicked on then off then stayed off.

i left it for a few days light still off and put it to the back of my mind then on friday i thought id go through the self diagnose process and it cam up with fault 34 (injector lift needle sensor / air in fuel) and fault 47 (crank position sensor) ? i then found out what the faults were and i started with the fuel filter, i un screwed the bleed screw on the bottom of my fuel filter and it sounded like air bubbling out closed the screw cap and cleared the faults went out for a drive and it seemed much better.

i thought id cracked it till yesterday the poxy mil light flashed up again and i checked the codes, it came up with fault 34 and 47 again :nenau

so today i went out for a drive and noticed the truck seemed to miss a beat when just cruising at 35 mph in 4th gear, a bit like i took my foot on then off the gas pedal for a split second (which i didnt)

also this evening when slowing down in 2nd gear on overun it felt like the truck was bunny hopping and a i also tried it in reverse and i done the same thing.

there was no sign of the mil light flickering on at all but im guessing its all part of the same problem ?

the truck is a hitachi maf engine which i think is the zexel pump


its a late 1996 tdi model

from research it looks like injector no.1 has sensor on it ?
how much do they cost and where from ?

how much does a crank shaft sensor cost and where from?

is it an easyish diy job ?

 

[ocelot]

HI, don't think its a crank sensor, if it is, its only a matter of cleaning it, but also could be the flywheel sensor.............
I had a very similar problem on an M reg swb maverick, same fault codes as well, after chasing through the faults and not fixing the car, it turned out to be the fuel pump.... faulty earth and the pump was dodgie as well........
Check that before spending on sensors......

 

[niks_terrano ii]

.

silly question but where is the flywheel sensor ?

also when you say fuel pump not the expensive one is it ?

does your one have the hitachi maf ?

 

[wildbri]

have you cleaned the MAF its easy to clean, I have found that when mine miss fires on acceleration a quick clean sorts it out. regards bri

 

[ocelot]

silly question but where is the flywheel sensor ?

also when you say fuel pump not the expensive one is it ?

does your one have the hitachi maf ?

flywheel sensor is top dead centre on the clutch housing, unfortunately you have to take the clutch housing off to get at it (changed my clutch this march and did it then) if you look behind the inboard end of the rocker cover around the back of the injector rack, you'll see a pair of cables going into the flywheel housing...... thats the sensor cables.

I have the bosche maf as well, clean very carefully with a little bit of WD40 or white spirits and soft kitchen roll, be gentle tho......

I have the bosche system on my car but you can get a new fuel pump (the one which fits in the tank) from a breakers/motor factor relatively cheap........

 

[niks_terrano ii]

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hi bri i forgot to mention the maf also got cleaned unless the maf is duff i dont think it will be that also drove the truck with maf disconnected and it really struggles to pick up speed so i guess it must be working i hope

 

[clivvy]

I have had both these codes before. turned out it WAS the crank sensor and it WAS the No1 injector.

Both expensive. £120 for the No1 injector, but a DIY job, and £180 for the CKP, again, DIY job.

CKP sensor will lose its effectiveness the older it gets, its affected by heat, so probably seems fine when cold and for a few miles. You can try cleaning it, but with the age of your truck, I would give serious consideration to buying a new one. I arsed about with mine for ages, then I gave in, bought the new sensor, and hey presto was like a new car.

As for the No1 injector, well, thats got a sensor on it, so it is probably that which is at fault, but you cant replace just that, you have to replace the whole thing. Again, did mine, and it made a hge difference, those two codes have never returned.

 

[niks_terrano ii]

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hi clivvy did your truck show the same symtoms as mine ? where did you get the sensors from ?

paul

 

[niks_terrano ii]

.

sorry clivvy forgot to ask is yours got the hitachi maf ?

 

[niks_terrano ii]

.

found this on fleabay

http://www.ebay.co.uk/itm/Crankshaf...rts_SM&fits=Model:Terrano&hash=item41600681f2

from gsf so should be ok shouldnt it ?

 

[niks_terrano ii]

.

yet another question clivvy was the injector easy to do ?

ive got a 530d bmw and they are a barsteward to get out

 

[Timbo_1975]

With regard to the Crank Sensor, take it out and clean it regardless, clutch dust and or starter pinion bearing dust will stick to it as its magnetic and can cause problems especially at low rpm's...

 

[ocelot]

I have had both these codes before. turned out it WAS the crank sensor and it WAS the No1 injector.

Both expensive. £120 for the No1 injector, but a DIY job, and £180 for the CKP, again, DIY job.

CKP sensor will lose its effectiveness the older it gets, its affected by heat, so probably seems fine when cold and for a few miles. You can try cleaning it, but with the age of your truck, I would give serious consideration to buying a new one. I arsed about with mine for ages, then I gave in, bought the new sensor, and hey presto was like a new car.

As for the No1 injector, well, thats got a sensor on it, so it is probably that which is at fault, but you cant replace just that, you have to replace the whole thing. Again, did mine, and it made a hge difference, those two codes have never returned.

Its one of those weird faults tho on the older vehicles that can confuse the ECU, its mainly because the ECU processor used the negative as earth instead of an invertor/isolator, this would cause the unit to give erratic readings, or inaccurate at the very least..... on the newer vehicles with an 02n canbus system, the earth in the ecu is to a large extent, isolated, thus it gives more accurate codes. its down to the age of the vehicle and type of ecu..... in the main.

 

[makeitfit]

96 TDi will have the crank sensor on the front of the engine
One 10mm bolt and out it comes, simples

 

[niks_terrano ii]

.

so do you guys think i should change the sensor in question ?
ill clean it first though

but in the past if its showing faults i wont be long before it completly gives up and with winter coming i really dont want the truck to fail.

what will happen if it just gives up one day will the truck start and run ?

as for the injector again will the truck start and run if the poxy inector sensor fails?

 

[ocelot]

pre 97 vehicles have older ecu's fitted, the main difference between pre and post '97, is the processor negative in the older units is common to the battery negative, in the newer units, a form of invertor/isolator is used to prevent earth loops and false grounding problems.

I can offer the following thoughts;
Check the fuel filter for water, using the bleed valve under the filter body.
Clean the maf carefully, the hitachi uses wires inside the body which are prone to damage, the bosche uses a voltaic plate. Dont forget the sensor cables, plug and socket, check for breaks and corrosion.
Check and clean the sensors, the crank sensor at the front of the engine with a cloth which has no static properties, foam cleaner is good for this but not concentrated.
The flywheel sensor is a lot harder to do as from memory, I think the bell housing has to be removed to get at this one.
Check and clean all of the junctions/joints using WD40 and seal with petroleum jelly...
Check the injector connectors/cable on No 1 for water ingress, corrosion etc, clean and seal. Do the same with the injector rack cables.
Put some shell diesel in the tank and add a bit of either petrol or redex to clean the injectors............ but not much, 2% say with 4 gallons.

If it is the injector, then that's expensive, but straightforward, the crank sensor is cheap enough and easy to fit...........

Good luck

Dave

 

[clivvy]

so do you guys think i should change the sensor in question ?
ill clean it first though

but in the past if its showing faults i wont be long before it completly gives up and with winter coming i really dont want the truck to fail.

what will happen if it just gives up one day will the truck start and run ?

as for the injector again will the truck start and run if the poxy inector sensor fails?

Hi Nik,

to answer your questions:

yes, similar symptoms but I had other issues as well. My symptoms included random stalling (CKP sensor when warm) and poor performance etc

Injector is expensive, but fairly easy to change, I actually made a guide if you want it, its not in the downloads section though. The only part I found even remotely tricky, was removing the fuel return section off all four injectors, but as in my guide, thats because I didnt remove the injector pipes.

took me about 2 hours, but im no mechanic and I was taking my time!!

The CKP was even more expensive but I did a lot of research into this, and I was 100% convinced I needed a new one. I tried two used ones from scrappies, same issue. They were simply too old, and not worth the other. As a test, I DIDNt clear my codes before fitting the new stuff. Fitted the new stuff, and the codes cleared themselves, so I was certani it wasnt the ECU playing up.

as for what will happen,I can hopefully help you there. You will start to get random stalling, but only when engine is running temp. It will start very slight at first, then liek mine, it'll just happen as you pull up to junctions etc.

As for other issues, the No1 injector will throw an incorrect signal to the ecu, so then the ecu will not send the correct signals for fuel injection, timing etc, everything goes out of sync a bit as it uses base settings, which of course get upset as the signals coe and go, so for me, it was a lot of gain/loss of power, smoke, bad starting etc etc personally, not worth the bother. I'm poor, but I thought sod it, bought the stuff I needed and fixed it, glad I did because I had arsed about for a very long time trying to fix it.

 

[ocelot]

Nice one Clivvy,
Looks like you had quite a time with your car, damned electronics..... it depends on the age of the car as to which type of ECU is fitted and thats a lottery sometimes... at least there's a fix for the problem, the one I fixed took about 2 months to sort out overall and I'm no mechanic, just an electronics engineer so should have been a breeze......... yeah, right......

 

[niks_terrano ii]

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hi guys where is the cheapeat place to buy the 2 parts in question ? paul

 

[clivvy]

hi guys where is the cheapeat place to buy the 2 parts in question ? paul

well, I got my CKP direct from NIssan, which I suggest you do BUT ring a couple of main dealers first, as cost varies.

I will get you a number for a palce a few of us have used for the injector, really nice chap and quick delivery, had no issues with my injector.