Fault P0340

This is the Forum for all your Peugeot Technical Questions, Problems or Advice.

Moderator: RichardW

MulleDK
Posts: 2
Joined: 27 Mar 2022, 22:05

Fault P0340

Post by MulleDK »

Hi I am getting gray hair over my 406er, so hope there are some in this fine forum who have the golden grain,
I have to admit with shame that no one at any mechanic forum in Denmark has been able to answer on the problem, and the answer from Peugeot DK, was: we have no idea

Peugeot hdi 2.0 engine code rhz

The car drove perfectly right until my wife backed up on a high curb and hung on her belly,
The visible damage was a slightly included exhaust, with a sardine can similar to the opening of the rear pot, and a towbar which was displaced, but noticed during subsequent driving that now the car began to put out and that it swung in revs if you try to give it additional gas.

Errors are reported as follows:

When the car is cold, it starts and runs perfectly, but as the temp rises, it starts to slow down, it starts at about 4200 rpm and the speed decreases the hotter it gets, and continues down to good. 2000 rpm at full operating heat, it is the same every time from cold start, and it runs 100% evenly and pulls exactly as it should until it rises in temp and the revs reach where it sets out.

I have had the tester on, who keeps writing P0340, which mostly refers to cam sensor, but it fails nothing, and have for safety's sake tested with another sensor, which is 100% ok, it does not change anything, and if I takes the plug off, then the engine dies at the first cut/puf, and can not start again until the plug is put on again, then assumes that it works as it should.
Have measured the cables from sensor to connector on ecu and there is connection.

crankshaft feel: if the plug is peeled off it goes miserably, then assume it is ok too

Exhaust, what we can see from the turbo and rear, then there are no / o2 lambda sensors, and have never had any, and always drove perfectly, so neither.

Can not immediately see if there may be a sensor hidden up by the manifold or elsewhere hidden behind the turbo or similar. ??

egr: here the plug is taken off, and has been for all the time I have had the car, and have driven perfectly like this for several years, if the plug is put on, it becomes heavy and loses 50-60% engine power.

Have had various connectors for temp sensors peeled off, and it gives poor engine running immediately, so do not assume this is also where the problem is.

Air mass / amount of maf or what it is now for a meter that sits on the suction .... if I take the plug off, there is no difference. ???

Have had peeled exhaust off at turbo, to see if there was a difference, no difference.

All fuses relays etc. are ok.

Has no fault lights that light up.
If I delete errors, and put the tester on, there are no errors, and it remains error-free in testing, right up to the first cut, where it immediately reports errors P0340

Test of the ECU reports 0 errors
In the test for crankshaft / camshaft synchronization, the return answer is yes

Someone who has an idea of ​​what triggers the beast, it should otherwise be a little grateful, as after this I got rid of the wife. ; D

Sorry for my translation english.
MulleDK
Posts: 2
Joined: 27 Mar 2022, 22:05

Re: Fault P0340

Post by MulleDK »

here are som video iby dif temp.
1. below 50 c.

2. 70 c.

3. 90 c.

4. cam sonsor plug off
User avatar
mickthemaverick
Donor 2022
Posts: 9190
Joined: 11 May 2019, 17:56
x 2491

Re: Fault P0340

Post by mickthemaverick »

Hi and welcome to the forum.
I have listened to the first 3 videos and to me it sounds like a rev limiter cutting in. Was the car run by a company who may have fitted a governor? If so perhaps the governor itself has developed a temperature related fault causing it to cut in too early!! Just a thought! Good luck with it, I'm sure someone on here will have more information to help. :)
User avatar
GiveMeABreak
Forum Admin Team
Posts: 28449
Joined: 15 Sep 2015, 19:38
x 3478

Re: Fault P0340

Post by GiveMeABreak »

It's my understanding that automatics are throttle-limited whilst in neutral.... though there does seem to be some difference between the first video and the third