2004 S40 1.6 fuel engine VVT
#1
04-21-2022, 06:18 AM
Join Date: Apr 2022
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
2004 S40 1.6 fuel engine VVT
We ran out of easy questions…
My son’s S40 started to have the VVT rattle since a while.
It’s the cyclic rattling sound like in this video
The difference between ours and the one in the movie is that the rattle stops when the plug is disconnected.
Meanwhile we have replaced the timing belt, VVT pulley and VVT solenoid valve but the VVT rattle at idle is still there.
The sound stops when I unplug the connector of the control valve.
Driving with the plug disconnected results in a sluggish engine.
The crankshaft sensor seems to work because when I disconnect its plug the engine stops.
Idle starts to go weird when I disconnect the plug of the mass air flow sensor.
Same for camshaft sensor. There is a reaction when I disconnect its plug: the rattle at idle then disappears. It didn't seem like a good idea to drive without this sensor connected so I didn’t try that.
But from these facts I conclude that these three sensors are OK.
There is an error message for one of the O2 sensors.
Something with the heating circuit. It’s the O2 sensor that was recently replaced by a garage.
I don't see a direct relation with the operation of the VVT.
I can reset the error message but it comes back in no time.
I drove around with a 5W bulb connected in parallel on the wires of the VVT control valve and that shows the following.
The light is continuously lit bright while driving and only dims when idling, but it doen’t go off completely.
At idle it alternates between bright and less bright, in sync with the cadence of cyclic VVT rattle.
The noise is not there at idle when the light is dimly lit, but it’s there when the light is brightly lit.
Back in the garage I connected an oscilloscope to the circuit.
The signal to the solenoid is a PWM and amplitude is approximately 14 Volts, alternating between 18ms width when the sound is there and 5ms when the sound is not, which accords to the indication of the bulb.
Too bad Imgur doesn't save sound. Trying at my best effort to post a link to the movie
https://i.imgur.com/A5Dx7B7.mp4
As far as I'm concerned, the VVT does exactly what the ECU asks him to do.
The only problem is, the ECU shouldn't open the solenoid at idle.
In Swedish: elände.
Does anyone have an idea?
My son’s S40 started to have the VVT rattle since a while.
It’s the cyclic rattling sound like in this video
Meanwhile we have replaced the timing belt, VVT pulley and VVT solenoid valve but the VVT rattle at idle is still there.
The sound stops when I unplug the connector of the control valve.
Driving with the plug disconnected results in a sluggish engine.
The crankshaft sensor seems to work because when I disconnect its plug the engine stops.
Idle starts to go weird when I disconnect the plug of the mass air flow sensor.
Same for camshaft sensor. There is a reaction when I disconnect its plug: the rattle at idle then disappears. It didn't seem like a good idea to drive without this sensor connected so I didn’t try that.
But from these facts I conclude that these three sensors are OK.
There is an error message for one of the O2 sensors.
Something with the heating circuit. It’s the O2 sensor that was recently replaced by a garage.
I don't see a direct relation with the operation of the VVT.
I can reset the error message but it comes back in no time.
I drove around with a 5W bulb connected in parallel on the wires of the VVT control valve and that shows the following.
The light is continuously lit bright while driving and only dims when idling, but it doen’t go off completely.
At idle it alternates between bright and less bright, in sync with the cadence of cyclic VVT rattle.
The noise is not there at idle when the light is dimly lit, but it’s there when the light is brightly lit.
Back in the garage I connected an oscilloscope to the circuit.
The signal to the solenoid is a PWM and amplitude is approximately 14 Volts, alternating between 18ms width when the sound is there and 5ms when the sound is not, which accords to the indication of the bulb.
Too bad Imgur doesn't save sound. Trying at my best effort to post a link to the movie
https://i.imgur.com/A5Dx7B7.mp4
As far as I'm concerned, the VVT does exactly what the ECU asks him to do.
The only problem is, the ECU shouldn't open the solenoid at idle.
In Swedish: elände.
Does anyone have an idea?
Thread
Thread Starter
Forum
Replies
Last Post
peace562
Volvo S40
22
02-20-2015 07:39 PM