Cam sensor

[keeforelli]

Hi guys


i have seen many posts about replacing cam sensors- was wondering what they do and what faults a faulty one can cause?

[markren2004]

the cam sensor monitors the camshaft spinning ...it's just one of the sensors (and the TDC sensor) that the CPU Brain users to determine when to fire the spark plug..not very interesting really.
A failed sensor will light up the Engine mgmt light on the dash upon starting.
they can cause poor starting or stalling.

[keeforelli]

cheers!!!!......i still have warm running issues despite changing just about every thing that could cause this...cam sensor the only thing left- tho has never shown on a diagnostic and only time engine mngmt light has come on was for a coil....fairly resigned to the fact now that my car just wont work the way i want it to....

[markren2004]

cheers!!!!......i still have warm running issues despite changing just about every thing that could cause this...cam sensor the only thing left- tho has never shown on a diagnostic and only time engine mngmt light has come on was for a coil....fairly resigned to the fact now that my car just wont work the way i want it to....

What are your warm running issues ? have you made any modifications to the car? and what work/parts have you already had done/replaced/checked?

[Jonault]

Have you had the coolant temperature sensor replaced?

[keeforelli]

HI GUYS!!

i have had done-
replaced coolant temp sensor..
replaced TDC sensor....
cleaned throttle housing.....
replaced all coils with new renault approved ones...
full service....
run car on premium hi octane (shell v max ) fuel..

when its cold feels like it has the proper power and throttle response.....even when its displaying the rough characteristics...its just when warm through properly that it plays me up....so as follows...

each time i have some work done..esp throttle body..it ran great initially....then i will drive along a few days after and each time get a sudden weakening in response higher in the rev range with poorer throttle response...like it just switches to rough or the ECU changes the running of the engine..coupled with rougher running and a smell of fuel from outside if starting the car from warm....it will actually start from warm now for all that...but has a very lumpy idle...

other symptons.

poor acceleration/mid range./throttle response...can put foot down..hesitate for a while..then suddenly go..

in second or any light throttle opening the car will kangaroo slightly or hesitate..ie 20 in 2nd or 60 in 5th...so i have to kind of apply and release pressure to maintain a constant speed if not much throttle is required..this always happens when the car starts running roughly....

and on going round roundabouts or sharp corners and accelerating out the engine again can feel slow to pick up with uneven pull....

noisier...sounding strained...like its being ragged when it isnt...

i ran the fuel low recently, and this caused rough running apparently..as on going round a sharp corner..felt car jump..and this was air/crap being dragged through the system from the fuel tank causing a slight misfire on one cylinder/coil on diagnostic and also a fuel system fault code too.....but this was reset and i was told not to run it low again, use a good injector cleaner on a tankful and not to use cheap fuel which i havent...this cured it for a while

then..on the service 2 weeks ago the air filter housing was left loose leaving me driving a very throaty car that felt like it performed better...had this corrected a couple of days after and just wondering if this one instance could have caused a fault with the fuel mixture which needs resetting as car was not put on diagnostic after ...

any thoughts?.....im bored of the garage and losing the will...its becoming an obsession!!!

[keeforelli]

sorry guys thats quite a lot of info.....would there be any thing left to check?

[Jonault]

Spark plugs?

[keeforelli]

Hi jonault


these were replaced in the service...i can only think the ECU is adapting to the constant stream of new info with all the new equipment and changes....it appears to have switched to good behaviour again- can the ECU take time to adapt? make a noticeable difference over an amount of time?

the mechanic did ask me who owned it before me as he was wondering if it had been driven slowly/short distances???

does the car adapt to driving style?....i think i have read and heard it does?...he told me to make sure i drive it 'properly' , ie not hang about/give it some/ longer runs etc to reset the ECU as my car is ex motibilty and had only done 18000m in 3 years when i got it a year ago...possibly left standing for some time too...

almost like i have to run it in again?

could this be right?

[AndyJohnson22]

I don't think you have a problem with the Camshaft position sensor as the 14. 16V doesn't have one!

You MAY have a problem with the IAT (Inlet Air Temperature) sensor in the inlet manifold. This is cheap & easy to replace, maybe worth a try?

Also, maybe the Lambda sensor is faulty, but this usually shows up a fault code so seems unlikely.

[andywills]

if the car adapts to driving style, get the mechanic to reset it back to factory defaults

[markren2004]

I don't think you have a problem with the Camshaft position sensor as the 14. 16V doesn't have one!

You MAY have a problem with the IAT (Inlet Air Temperature) sensor in the inlet manifold. This is cheap & easy to replace, maybe worth a try?

Also, maybe the Lambda sensor is faulty, but this usually shows up a fault code so seems unlikely.

I was thinking along the same lines, AirFlow meter, Lambda sensor (this would also show up in the MOT emmissions), catalytic convertor,throttle body, blocked/split breather....the problem is there are umpteen things it "could be" and unless youve got a bottomless wallet there is no real point in going down this route.
I'd suggest finding a good old style one-man band backstreet mechanic (one comfortable with a spanner rather than a computer), be prepared to leave the car with him for a few days, give him all the possible info you have and see what he comes up with.

[AlunWJS]

with my 2004 1.6vvt I've had the constant problem of the toxic emmision light, pretty much since I've owned the car. The only fault that's ever been diagnosed is that a coil has failed, and Renault have shown no interest in investigating the problem, just trusting that the fault is diagnosed correctly by the computer. The car runs fine, the only issue is that it gets a bit lumpy and the light starts flashing when idling. This NEVER happens when the air temperature is above 19/20 deg/C.

Having read the above thread does anyone else think that this may be indicative of a failure with the inlet air temperature sensor? If this sensor fails will it bring up a fault code? (Normally I've been told there is no fault, or the fault is a failed coil, which it isn't as the car drives fine!)

Is this sensor easy to test/replace?

[keeforelli]

hi people!!!


thanks for that- i do have a local garage that are interested in getting this sorted and they have been really good...just need to nail this now....im wiped out cash wise so gonna have to wait- whatever is up with the car is intermittant but comes back more often than not...

it is getting tiresome however- i may well have to leave it with them- tho the inlet sensor thing would be a good heads up for them!!



TA!!!!

[markren2004]

found this general car troubleshooting guide site that might describe your issues ? It has a wealth of really good info.
http://www.aa1car.com/random-misfire/