Error code P1671 (still after replacing VVT solenoid)
 

Hello.

Recently I bought a V70 2.4L from 1999. The check engine light was on and the buyer showed me a printed document from a workshop where they read the error code as "P1671 Fuel injector Voltage too low". It could also be "voltage too high", I do not have the document here right now but it probably doesn't matter.

However, when I look on the internet all the information I find refers to a VVT Solenoid problem, not a fuel injector one. I assume the scan tool they used just got it wrong. Today I replaced the VVt Solenoid (bought it on eBay, not original from Volvo) but the engine light came back.

I checked both the old and the new solenoids for continuity and both seem healthy. I measured their inner resistance and got some 4kOhm, which seems to correspond to a normal value according to info I could find online. I did not have the chance to test them connecting them directly to the battery as I could not find proper cables to do so.

Now I wonder two things:

- Could it be that I connected the two cables the wrong way? In my original plug there were no 1 and 2 numbers, only in the new plug that I bought from Volvo. I think I connected the green/orange cable to the 1 pin.

- Could this error be caused not by the VVT Solenoid but by the camshaft position sensor? I have found some forum threads on the internet that suggest it as another possible cause. I would say I can hear sometimes a clicking sound from the area where this sensor is placed, but I do not know if that could suggest a problem with it.

Tomorrow I will try to check the camshaft sensor if I find some time. Is the following info correct?

- 10 volts at pin 3 (ignition on).
- 12 volts at pin 2 (ignition on).
- 0 Ohm between pin 1 and ground.

Other than the engine light coming up, the car starts and runs very smooth although idle is unstable sometimes. It is mainly a problem because I need to pass the MOT and I can not do it as long as the engine light is on.

Today I tried to check voltage at connector pins but this model has the connector deep down over the gearbox and can only be accessed after disassembling the air intake housing. So I opted for directly ordering a new camshaft position sensor and simply returning it if it doesn't solve the problem.

Any ideas if the problem persists?

When the camshaft sensor died on our 1998 S70 a couple of months ago the code was P0341 (or something close to this), so a faulty camshaft position sensor has a code of its own.

Also, our S70 was difficult to start and would not idle properly.

Apologies if this is a basic question, but did you clear the code before restarting the car? If the code is logged then it'll probably be permanent until the fault is fixed and the code is cleared.

Jack

The code was read by the previous owner when he took it to a workshop to pass the MOT. I disconnected the battery several times and the light disappears, but soon comes again. The problem I have is that I live in Germany and without a valid MOT I can not even register the car, so I can not easily move it around to take it to a workshop again and I do not have a device to read Volvo codes.

The original code reading talks about intermittent voltage at fuel injector 6 (?), or at pin 6, or something referring to a 6. But I take it that it was not read with a Volvo device and it just gave a random name to the error code, because I've not found anything of that kind on the internet.

https://i.ibb.co/2SQDYyj/diagnose-p1671.jpg

"stromkreis einspritzventil 6/ unterbrechung" seems to translate to;

Circuit injector 6/ open circuit.

That just doesn't sound right, How could circuit 6 be faulty on a five cylinder engine?

If it was mine I would have the car trailered to a mechanic who can properly read the codes with VIDA; or a mobile mechanic who could come to you. At least you would have a known starting point instead of taking someone else's dubious diagnosis as fact.

Edit: This may help. https://www.matthewsvolvosite.com/fo...oogle_vignette

At first sight I did not see any damaged cable when I replaced the solenoid, but I also did not open the looms that are still intact. I'll take a look into that. I expect to receive the new CMP sensor tomorrow or Thursday.

Problem solved. Yesterday night, before starting taking hoses apart to change the camshaft sensor, I decided to take a second look at the wiring loom from the VVT solenoid and found this.

https://i.ibb.co/QcB4VFZ/photo-2024-03-28-19-16-30.jpg

Disconnected the battery (to delete the code), cut the wire and re-soldered them. I let the engine run for some good 20 minutes, reved it up a couple of times and engine light did not come out. Passed the MOT this morning with no issues.

Could have saved some head scratching if I checked the wiring better the first time, but I'm quite happy I did not need to change the CMP.

Thank you all for your help.

PD: Could a moderator edit the title of the thread as "Solved" and include a link to this message in the first message to indicate the solution?

Good result! Annd.... no cost, other than a little time. :thumbs_up:

That wire getting smashed by the bolt means the plastic cover was removed before. Probably some ignition problem, since the coils where marked 1 to 5.

Seems a bit sketchy to me the way those wires run over the head below the plastic cover. They must reach really high temperatures.