Engine fault.

John Gordon

Paid Member
Hi,

Clio has been down on power for a while. Feel's like the VVT is not functioning. When over 4500 RPM the induction noise now sounds like I have an open filter.

I've had an engine warning light on and the status "Check Exhaust" (My car is German, this is what it translates to).

I've had the fault codes read and had the following fault codes...

P0325 - Knock Sensor
P0340 - Camshaft position sensor "A" Circuit.

I replaced the Camshaft position sensor. The car idles and pulls a little smoother, however, the lack of power and the weird induction noise is still there.

Any ideas what it could be?

Thanks
 
If the cam sensor fault is still there it’s possible a cam pulley has drifted a little as they are friction fit, might be worth getting cam timing checked as it references the cam timing to the crank sensor and will throw up cam sensor faults as it can’t decipher between incorrect timing and the cam sensor reading incorrectly and will probably have one fault code for both

We used to get similar on the bmw engines and it would throw up one or the other cam sensor but it was the timing gears that had slipped a fraction, it also sounds funny on induction and lost power

Just a thought

Also it may be worth (and I’m not sure if you need to or not!) reprogramming basic settings... the bmw crappy Peugeot engine used to adapt itself to the fault so it still ran, but when you corrected the fault it would effectively still run the altered map until you reinitialised the auto adaptives in the engine management so it effectively relearn how to run correctly once more, even if it was a coil pack down, it was a pain in the arris as it took 40 mins and had to be done from cold
 
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Hi,

Just as a little update.

After I changed the sensor the engine warning light remained on the dash. I cleared this with the OBD2 and I set the ECU to default parameters by discharging.

The light did not come back on but the OBD2 would show the two errors coming back. I Cleaned the plugs on both the Knock Sensor and the new cam position sensor then went for a really long drive.

Low and behold... The car slowly moved its power band back to lower down the rev range and my torque/power came back. The induction roar is still there but less so, and now I've got exhaust rasp back.

So, touch wood, seem's to be ok.
 
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Hi All.

I'm still struggling with this fault.

As per the first post, I lost all of my mid-range torque. Almost as if the VVt was no longer working. The characteristics of the engine changed along with the sound.

Here's the list of changes I've made in order to try and resolve this.

Cam Position Sensor (Old one was a little dirty)
Crank position sensor. (Old one was gunked up with oil and the metal tip was buried in crap)
Dephaser.
Throttle body cleaned.

After making these changes the engine is a lot smoother. But, I still have the following problems.

Rough Idle. The car is hunting and the revs fluctuate.
I've got no power lower down. Between 2.5k - 4k the engine is gutless.
Engine management light is on with the message "Check Exhaust"
P0340 - Camshaft position sensor "A" Circuit fault code on the OBD.

Known problems with the car.

My exhaust is leaking at the rear joint (Shitty pure motorsport system keeps coming loose on that joint)
The fuel pump may be weak (it's not as strong on the lower fuel levels as it is when its above 1/4 full, car runs worse when below)

I really don't know what else to do. I don't want to keep throwing new sensors at it. Anyone got any ideas where I should look next?
 
Looking at your history you have nothing but problems did you ever do the timing belt yourself. Engine faults since January do you have the resources (money/tools/space) to do the work. Some pictures of the car and engine bay, list any mods exhaust system setup mileage RH or LH drive we might have some idea of where to start it's difficult to help when we have nothing to go on.
I'll be at Assen with the BSB at the end of Sept. a few days before and one day after the event I can bring the Renault clip with me and knock off some of the fault lights and have a look around the engine bay for you. To me on the face of it sounds like the timing is out or the plugs/ ignition coils lambda sensors are not right.

If it were me I would give it a full service with the genuine oil, oil filter, plugs and air filter the exhaust systems needs looked at and if there is any of the cats fitted. A fuel pump tends to cause problems at higher RPM's as it's job is to move fuel and keep pressure up so if it fails it will be when the demand is highest = high RPM's and more fuel in the tank sounds like fuel contamination you might have to dump the fuel tank. An air leak could explain the brake clutch issue and the idle problem any leaks in the exhaust can cause issues is the temp gauge reading correctly or is it reading low all the time.
 
If he’s done the dephaser I’d assume the timing was checked and adjusted if out when he did that

Sort exhaust blows, even if it means a couple of 10mm long welds round the outer pipe opposite each other and some sealant to ensure it stays where it should after clamping up tight (if you ever need to remove the exhaust just grind the welds away but I’d not hesitate to weld it a little)
 
I’d also be taking some brake cleaner on every inlet joint (injector seals/gaskets etc) and seeing if the revs pick up
 
I did the cambelt myself with a few friends. We got the timing almost spot on. The cams were straight, but the tool was a little tight. It may be out, bit very slightly.
 
As long as you didn’t bend the cam locking tool and checked it was straight when you were done all should be good, it is easy to bend the room though... might be worth a check! If it’s bent, straighten it and put the timing right so it drops in easily
 
I’d check fuel pressure, for air leaks and also see if tuner who mapped it has an original map for it still and can put it back on, but if it ran ok after the map for a bit chances are it’s something daft, it could even be an ecu fault as it sounds almost like a coil driver is going down which I have had, a set of noid lights which you put between coil pack and plug and flash per fire if you like would show if one was not behaving, Ive also had a cracked spark plug do exactly what yours is, but it wouldn’t throw in a can sensor fault, I’d be focusing on timing, double check it and triple check it!

If all the above find nothing it’s weird stuff then! I once had a cam timing ring that had cracked that the sensor reads off and moved a little which did put cam sensor faults in also
 
Logically you have worked on the timing and are have cam sensor errors even after changing the sensor the faults need cleared then see when and how they come back. I would buy the genuine timing kit £150 from Renault parts Direct and check the timing again with the proper thickness and length of tools or get a specialist to check them or someone else. Give the car a service with correct genuine parts and oils (plugs, air filter etc.). If your still in the mood to change stuff the flywheel TDC sensor.

Give us the part numbers and the parts you used to do the timing belt thing there was a guy on the forum that lost power cam sensor errors had a faulty pulley the put a new one on better running but lost power turned out the replacement pulley was the wrong one for his car.
 
He’s done the crank sensor (tdc sensor as you call it) already :wink:

I’d still say it’s timing related to throw cam sensor faults, I’d put an identical car and yours on the diag and see how the cam sensor reads on both if there’s a parameter for it (sometimes isn’t!) and also the map sensor as if timings wrong it will throw that off and be allowing more air in or less so you’ll see it from the comparison of map sensors
 
Logically you have worked on the timing and are have cam sensor errors even after changing the sensor the faults need cleared then see when and how they come back. I would buy the genuine timing kit £150 from Renault parts Direct and check the timing again with the proper thickness and length of tools or get a specialist to check them or someone else. Give the car a service with correct genuine parts and oils (plugs, air filter etc.). If your still in the mood to change stuff the flywheel TDC sensor.

Give us the part numbers and the parts you used to do the timing belt thing there was a guy on the forum that lost power cam sensor errors had a faulty pulley the put a new one on better running but lost power turned out the replacement pulley was the wrong one for his car.

It was all genuine Renault parts. The cam sensor fault was the reason I did the cambelt as I thought it was the dephaser causing the cam sensor fault. But it remains with the new dephaser.
 
So Before this gets way out of hand and I withdraw from another thread, the name of the parts and what has already been renewed this is the Renault official naming of the TDC sensor and the CAM inlet sensor and the location that's why I put the word flywheel next to TDC sensor. So John what did you change I still think it could be timing as the CAM sensor is inlet and your talking about inlet noise and I was looking part number as genuine or not you could have been given a 172 Clio pulley instead of a 197 pulley that's all and we still don't know if the timing is spot on as your answer was not 100% spot on.

QUOTE "I did the cambelt myself with a few friends. We got the timing almost spot on. The cams were straight, but the tool was a little tight. It may be out, bit very slightly."

The engine needs turned over by hand several times and checked again was that done? after everything was torqued up.

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I've ordered a second set of cam seal (plugs) today, along with a proper Renault timing tool. The First tool I used was one of the cheap alloy ones and it bent. We tried to make it straight, but the timing may be out by anything from 1-3 mm. (Its not so much that it bent, but it twisted)

Changing the cam position and TDC sensors have made the engine a lot smoother, especially at low revs in traffic. So I think the electrical side of things is working as it should be, and its a mechanical issue with the timing.
 
If the tool bent you were tightening the cam bolts against it, you need to not do this!! Use a screw driver against the cam carrier lip through the cam pulley (I never cracked the variable one as I mainly did 182s and 172’s and adjusted the non dephaser cam and bottom none keyed pulley to suit the dephaser, if I replaced a depaser from memory I used the old belt and a oil filter strap tool to hold it still while I tightened it, you will bend a genuine Renault tool the same way, it’s normally the notched cam holder that twists a little, I used to straighten mine each time with a ruler in the vice to tweak it a touch if it needed it, very gently!