407 Coupe Engine/Gearbox fault

alexn2003

Member
Tadpole
Joined
Feb 4, 2017
Messages
26
Location
Canberra
I have had this V6 HDI coupe for several years. After about a year it decided that it would occasionally not accelerate when I put my foot down (hard) and then tell me that the engine pollution control was faulty. Several checks with Peugeot experts since then showed that the fault showed up in the computer as an imbalance in the air pressure sensors. After they were cleaned and eventually one sensor replaced ($200 plus) the fault continued. Very frustrating.

Then the second to third gear change in the Aisin auto six speed gearbox started to go wheee thunk as revs rose with a missed change. Off to the auto experts who said immediately that it was the auto valve body going wheee thunk and quoted me $2346 for the part plus $1000 for labour and fluids. Quick web search showed a group in UK who would send me a brand new OEM valvebody for a 2006 coupe for a paltry $711 including shipping. Arrived three days later and the auto experts slotted it in and flushed the gearbox. Works perfectly.

And surprise surprise the car now accelerates without a hiccup and there are no more engine management issues. Two lessons , don't believe the engine management software necessarily and the Peugeot parts dealers here are thieves. And a free plug for the UK One Stop Gearbox Shop!
 
407 V6 2.7 Twin turbo issues. it is a sedan 2006 build.

The twin turbo on this engine inoperative, First turbo died and eventually after few thousand KMs the other one also stopped working, At present, it is gutless but driveable, any help to resolve the issue would be much appreciated.

It also have the second to third gear change in the Aisin auto six speed gearbox started to go thunk as revs rose with a missed change.
 
There are certainly repair options with this gearbox and these will assist in understanding it:
Sonnax Adjusting Clutch Control Valves on Aisin FWD 6-Speeds
Sonnax Aisin AW Linear Solenoids
There's plenty more on this gearbox at the Sonnax website.

If you start fiddling with adjusters and maybe changing single solenoids on a worn valve block, you might fix it or you might just be exposing the next weakest hydraulic part. If you have time to fiddle or are happy to DIY Sonnax, gives some options. In commercial terms, a repairer wanting to avoid comeback and ongoing problems for their customers will most likely choose the new valve block. Ignore the AW5 info in the second link as the solenoids are different, but drilling a scrap pan and adjusting on the fly with speedo cables has merit for the adventurous tinkerers!

As to the lack of power, you may have issues with vacuum, fuel filter blockage, particle filter blockage, split boost hose, coked up intake etc. that are worth addressing before spending money on turbo parts. Why have the turbo's stopped working? Maybe, you do need to replace them, but look at the cheaper items first and get someone to read the fault log to see if that helps. Don't forget to check the injector return pipes, which can leak at the little o-rings and the plastic thermostat housing and water outlet down the front, both of which become brittle and leak ... badly.
 
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Great to know.

Bloody AL6's - mine is doing the same thing.

What exactly did you order from te UK? Have you got the part number, etc.?

TIA
 
Go to One Stop Gearbox shop and fill out their forms. You don't need the part number. If they get it wrong you can send it back. They do not get it wrong! Mine arrived in about 3 days and was one third the price of the Australian dealer (including the airfreight) for a brand new part.
 
How many kms on your car alexn2003? :)

All these 407 Hdi problems are starting to become worrying. (Mine upto 29k km now!)
 
Yes. I have a new one and i really would appreciate any ideas or help. Low Oil pressure.

Car is 2007 407 HDi coupe. 2.7l engine. Mileage 80000. As soon as I bought this car with 70000kms I had it fully serviced by my local mechanic in whom I have my utmost trust as he has serviced our family cars for several years including my wife's 307 2l hatch.

The car is wonderful and until recently met all of my desires. On a very warm day earlier this year after driving for an hour I had a surge of revs, a sudden acceleration and a low oil pressure warning followed by a STOP. I pulled over and stopped checked the oil and after allowing everything to cool down drove to a more convenient spot to survey the damage. could detect nothing. RACV could think of nothing and suggested that I drive home.

Long story short I hope. My mechanic suggested that i take it to an expert in the outer East of Melbourne. He checked it out, replicated the fault and suggested a flush and changed the oil and filter to an ELF MMX oil. Excellent. Everything worked - for about 2000kms. When we changed the oil filter there was evidence of metal fragments in it. Visible. i still have that filter. Now, that motor will run for about an hour and then shows low oil pressure when the revs go below 750 or so. I cannot adjust the idle revs because they are set by the programme in the ECU.

I need help.

What should I do next. Where do I look? Is it the oil pump? Bearings? Crankshaft big end or thrust? Is the pick up blocked? What is the smartest next step. Drop the sump?

I checked the oil pressure sensor and the new one behaves the same as the old. Cheap test really in the scheme of things.

I like this car and i want to keep it so I wish to sort this issue in the neatest and most cost effective way.

This engine is used in many places, Ford Territory, Land Rover, Jaguar and i have not found any help from those forums, though I am not an expert at those searches. My friend had a trouble free run in a 407 coupe car of the same year until he got up to 290000 kms and only got rid of it when he had a serious collision when he did serious damage to the cooling systems which his mechanic was unable to fix.

I live in hope.

Thanks all for your help.
 
I have worked on a bunch of these from new low and high mileage and have never seen this I would be taking to pan off and checking the strainer are you running 5/30 or something else?


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When the fault Low Oil Pressure first appeared it was shortly after 80000 Km service and it had Phoenix 5W-30 C3 fully synthetic in it. When the filter was changed and the engine flushed the replacement oil was ELF Solaris MSX 5W-30. Mileage was 84398. Current mileage is 86596. There does appear to be a slight increase in fuel consumption since i first got the car , but I have not measured it carefully. The computer indicates ordinary levels when going along the open road. A comparison with another similar car in my area suggested that mine is more economical then his so I should not worry. When I bought the car and had it serviced at 71807Kms, he put Phoenix Fully Synthetic 5W-40 C3 in. I never noticed that until now. I shall talk to him on Monday about that and seek confirmation.
 
From memory, the DT17 engine was released as wanting 5W30 C2, but the 2008 lube guide also allows for 5W40 and 10W40 A3/B4. 0W30 is apparently unsuitable.

ACEA notation. First letter refers to the engine type:
A = Petrol and petrol/LPG dual fuel engines
B = Diesel engines
Number refers to the following types of oil :
2 = Mineral oils
3 = High performance oils
4 = Oils specific to certain direct injection diesel engines
5 = Oils with very high performance, favouring lower fuel consumption

ACEA specifications low ash oils:C3 : Moderate ash content
C2 : Moderate ash content and fuel economy
C1 : Very low ash content and fuel economy
C4 : Very low ash content and fuel economy

Why the initial 'surge of revs'? Any ideas as to what caused that? Your foot or the car by itself? You could get a surge of revs if the transmission goes into limp or refuge mode and selects 3rd. It may seem normal again after a restart. Would that describe the situation? A bad pedal unit or a wiring fault perhaps?

Did the fault log reveal anything useful?

Does it really have low oil pressure or is that a false warning? It would be possible to confirm it with a gauge as switches, senders and rat-eaten wiring can cause phantom issues.

What filter is/was in the car? Factory, Purflux (a factory supplier) or something else? There have been cases (thinking older Belingo here, not 2.7HDi) of good quality substitute filters fitting and being OK most of the time, but causing oil pressure loss because they were different internally.
 
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1. The initial surge of revs. This occurred just after getting over the high point of the Westgate Bridge and I took my foot off the accelerator as i was going downhill,because i was exceeding the speed limit. I suspect that that surge was just the gearbox changing down and the apparent acceleration that you feel when the car free wheels for a moment. I have experienced the same in my wife's 307.
2. Fault log has revealed nothing apart from a recent one on the air pressure sensor on the intake.
3. False warning. Yes I have thought of that. I will get a Tee piece made but at the moment I do not have a pressure gauge with a suitable range. The only ones that I have are for cylinder compression (too high) or carburetor vacuum (too low). I thought that just trying a second sensor might be a low cost trial. I need a tee piece because you cannot start the engine without the pressure sensor connected, but I plan to do this. However, I am having difficulty in finding out what the pressure v rpm reading should be for a good engine. If anyone knows, I would appreciate it. I have noted that the Ford engine in the Territory which does not have a particle filter fitted uses an oil 5w-30 which has lower viscosity at 100 degC than specified for the 407 with DPF.

4. The filter in the car the first time this problem appeared was Mann Filter Hu 934/1. The replacement is L371 1109X7 of brand unknown. The part number looks like the standard Peugeot part number for a filter and as that workshop has the Reagan's spares guy living not far away and conveniently dropping stuff off on his way home, i expect that the filter came off the Peugeot dealer's spares shelf. I shall try and check this tomorrow as well as confirm the actual Poenix oils used by my local mechanic.
5. The matter of the oil spec. The Phoenix claims to meet both the C2 and C3 standards. It's low ash or very low ash. I think that the spec thing is covered, but the Phoenix does not claim to have certified as meeting the PSA specs, though a comparison with the oils that have been approved against them suggest they would.

My current investigation to be followed up tomorrow is to find out precisely which oil was used by my local mechanic, because I have discovered that there are a number of 5w-30 diesel oils and more than one c2 or c3 oils. Seems there is a variance in 100deg viscosity, not only between brands of oil but also between oils by the same manufacturer all meeting the same spec.

One thing that I noted was that after the first occasion, i drove the car home, not in limp mode, but modestly. After about 30 kms on the freeway when I got to the off ramp, slowing from 100 kph to 60kph uphill, I got the warning again. I really cannot decide if it is a pickup issue at lower revs or just that the oil has become too thin. Hence request for advice and info and help.

When the oil was changed from the Phoenix to the Elf, they noted that the engine oil ran very hot. The oil temperature gauge in the car indicates with the needle vertical (normal I presume) a temperature of 116 degC. I measured the temperature in the sump using a thermo couple and it was 109 deg C. However the cylinder wall measured out at up to 140 deg max. Water temp has always been normal and the cooling system has been checked out.

Thanks for your interest.
 
NOT meant to sound rude: Have you tried Dr "Google"? The are lot of listings with this fault.

I just Googled "low oil pressure 2.7 diesel" the following came up on a Jaguar site (Jag, Ford, Rover all use this motor): "This car has a DPF regen problem. If you keep using it, you will either knock the crank bearings out, or suffer a diesel run-away event.."

Could give this some thought. :)
 
Thanks BIGRR. Yes, I had tried Dr Google but with different search terms. Yours was much more effective.

Depressing reading all 7 pages of it, but I did get a most important piece of information that i was looking for and that was the normal oil pressures, what is unacceptably low and what is unacceptably high. i shall now proceed with the next stage of examination before i spend real money. The referenced post showed an issue an almost exact replica of my experience. His outcome was sad though. His engine is almost finished. We shall live in hope.
 
With regard to the 2.7 V6 HDi in Fords, and maybe others, the plastic thermostat housing and the other troublesome piece are replaced with metal pieces and they have just the 1 turbo. When talking to the first owner of a petrol V6 auto Touring he reported initial issues with the auto at 92,000 by 106,000 and 2 visits to Peug mechs and/or auto specialist the issue wasn't cured so he sold it. At 113,00 a well regarded Peug dealer looked at it, reported on the worsening auto problems and never saw it again. Keen to discover more about the Aisin 6 speed that I'd previously thought was a goodun my friendly Ford service manager relayed their experiences with very similar box. Though Ford says no need to service till 250,000, his experience was that if not serviced with oil and filter change by 60,000 there was a high risk of failure by 75,000. Since then my friendly Peug dealer mech has told me of having recently replaced 2 aisin 6 speed auto valve bodies in cars with around 200,000 on the dial.
Hope that may help save somebody some misery.
 
Yep.. Same advice here from Mark Holland .. these boxes DO need oil changes[emoji106]. No such thing as sealed for life


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Am aware of the valve body plastics so my plan was for preventative oil replacement, cooler and buy a replacement before it needs it.

Surely in this climate the coolant heater could be removed and take away the heat input issue all together. Its never that cold here surely?
 
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Sorry for the delay. My coupe has 175 000 kms on the clock but has had a new engine (the temp gauge is defective and happily reads air after there is no coolant, the oil temp then goes way up, and the engine is cooked). After 40 years of buying Peugeot my patience is being tested.
 
You need a coolant loss detector and an oil warning. I will now after your experience. This coolant into the gearbox is going, if I have anything to do with it, might be required in -20 C but not here.
 
Got to Say here .. I might have been lucky..
BUT.. My Daughters 2006 Diesel 407 was doing the BIG Rev/SLAM into 2nd and 3rd gear change .. scary..
Car has the Aisin TF-80 SC Gearbox..
Went to U-Pullit wreckers here in Adelaide, Found a 2007 307 with same box..
A dozen torx screws, carefully unclipping all the electrics, remove the valve body - An Easy extrication - especially when half the front of the car is already missing/removed..�� - plus $32 at the counter and new oil $60... on the way home.
An hour later . - all sorted :D Happy Puggy and under $100 ..
 
Mine has done nearly 180 000 kms before these problems started. Now rectified but very irritating to find someone who knew what to do and then have to run the gauntlet of the Peugeot dealers exorbitant prices for parts. Runs well now though.
 
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