406oc.co.uk

Greetings

Got a couple issues in my hands, so sorry if some of these aren't engine-related...

'Very' long story short, my HDI has been giving me more than a fair share of grief.

I can't seem to be able to get rid of a handful of gremlins inside the engine bay.

Engine is sluggish and cuts off at 3000rpm, car struggles to get past 90kph, much less beyond... Tacho and temp indicators seem to have a life of their own, and either they work normally or not at all.

I've tried everything I could remember. Checked MAF, ran with it unplugged; no change
The turbo and intercooler had leaks, so those were refurbished and replaced, respectively. The crankshaft pulley and timing belt were on their way south, so those were changed too, as well as oil and filters and all...

I'm now looking at a high-3-digit cost for all this, and it all feels exactly the same... I'm on my wits' end, here!


Would gladly appreciate any helpful advice or opinions

Cheers, everyone

If it runs the same with the MAF unplugged you need a new MAF!

Is there any sign of moisture under the drivers side carpet?

Peter

jonsowman wrote:If it runs the same with the MAF unplugged you need a new MAF!

Got one ordered, should be able to check that in a couple days... here's hoping.

PeterN wrote:Is there any sign of moisture under the drivers side carpet?

Peter

Nope, none whatsoever.
It's been pretty dry weather around here, so if there were any moisture, would have to be from one of the reservoirs... no?

The reason I ask is that you can get an accumulation of water under the carpet and there are a whole bundle of connectors there and when they get wet the electrics can go completely haywire.

Peter

PeterN wrote:The reason I ask is that you can get an accumulation of water under the carpet and there are a whole bundle of connectors there and when they get wet the electrics can go completely haywire.

Peter

I have not noticed anything, but I will double-check once I can.

I'm now looking at a high-3-digit cost for all this, and it all feels exactly the same... I'm on my wits' end, here!

I can imagine...

Things to do (in order of priority):
1.) Stop spending money
2.) Start analysing the problem

As for 1: you can replace stuff forever, but probably only one or two things are really wrong. Don't end up replacing your whole car

As for 2: it is best to get hold of a "Lexia" cable and "PP2000" software (or somebody that has one to help you with). There will probably be fault codes that give -at least- an indication where the problem could be.

The turbo and intercooler had leaks, so those were refurbished and replaced, respectively. The crankshaft pulley and timing belt were on their way south, so those were changed too, as well as oil and filters and all...

That is not wasted money... unless you stop now and do not fix the problem

Checked MAF, ran with it unplugged; no change

AFAIK, the MAF serves as a (last resort) smoke limiter. If the MAF says "we're getting no air (gasp)!", the engine ECU will limit the injection of fuel. With the MAF unplugged, there are no limts (but a fault code will be stored in the ECU). So if unplugging your MAF makes the car run happily again (except maybe for a lot of smoke when flooring it), it is the MAF. But that didn't help, so chances are that the problem is somewhere else.

Just some things that come to my mind:
- Coolant temperature sensor --> ECU might think engine is running cold
- Fuel pressure regulator on the high pressure pump --> easy to clean or replace
- Turbo wastegate always opened (or closed, never seem to remember the way this thing works) --> no inlet air pressure build-up. Vacuum OK?
- Electrical problems (as PeterN already pointed to)
- Fuel injectors

Have a look here: http://www.pug306.net/forum/threads/127 ... -read-this

frog wrote:

Things to do (in order of priority):
1.) Stop spending money
2.) Start analysing the problem

Yea, that's what I'm trying to do 'now'...

frog wrote:
As for 2: it is best to get hold of a "Lexia" cable and "PP2000" software (or somebody that has one to help you with). There will probably be fault codes that give -at least- an indication where the problem could be.

I have a bluetoooth OBDII dongle and Android App that I used to read the ECU faults with in a previous car... will try that one, and see what faults I can get... (and start looking for a PP2000 solution)

frog wrote: Just some things that come to my mind:
- Coolant temperature sensor --> ECU might think engine is running cold
- Fuel pressure regulator on the high pressure pump --> easy to clean or replace
- Turbo wastegate always opened (or closed, never seem to remember the way this thing works) --> no inlet air pressure build-up. Vacuum OK?
- Electrical problems (as PeterN already pointed to)
- Fuel injectors

Thank you SO much, I really appreciate this!
I'll look into checking all these as soon as I can. Just need to get an idea of where each one of them is located.

The thing that baffles me the most is that the mechanic 'claimed'... (special emphasis there on the word 'claimed) to have checked the car and even doing a motorway run with positive response from the engine, reaching 170kph stable...

Not that I'm one to keep on dashing through the tarmac at such speeds... (not 'all' the time, at least ) But once I took the car or a run myself, the dials started acting up, and it got sluggish again.

Thanks for your input

Cheers

Ok... A little 'more' advice

That Android app I mentioned before has a real-time readout function for a bunch of sensors, plus fault list and clear. The OBD II connector seems to work ok (although I'm still looking for a PP2000 solution).

Gonna try and take the car to some quiet place where I can give it a few good revs, and see what results I get back

Any particular faults I should be on the lookout for, or any sensors I should focus on?

That Android app I mentioned before has a real-time readout function for a bunch of sensors, plus fault list and clear. The OBD II connector seems to work ok (although I'm still looking for a PP2000 solution).

What app are you going to be using?

My experience is that most of the (Android) apps are pretty useless I tried to use "OBD Car Doctor" (https://play.google.com/store/apps/deta ... dcardoctor) which at least connected, but it gives hardly any information. And often the fault codes be displayed with the wrong description; the app will give a description that may be valid for one manufacturer but not for another.

Best is PP2000; it gives all the information that is stored in the ECU and it at least translates the fault codes to the description that the engineers of the 406 had in mind. And the translation from French to English is already a pretty tough one for them

Any particular faults I should be on the lookout for, or any sensors I should focus on?

Just post whatever you get...

Thanks for your help.

I'm using the Pro version of Torque ( https://play.google.com/store/apps/deta ... owl.torque ) and a Bluetooth OBD II connector. Seems to work at least half decently.

The faults I got were "P0243 - Turbocharger Wastegate Solenoid 'A' " and "P0380 - Glow Plug/Heater Circuit 'A' "

The faults I got were "P0243 - Turbocharger Wastegate Solenoid 'A' " and "P0380 - Glow Plug/Heater Circuit 'A' "

Glow plug(s) are not the problem, you can run perfectly without them. My HDI ran for over 2 years with two of them not working, I never noticed.

The "P0243 - Turbocharger Wastegate Solenoid 'A' " message could indicate where your problem lies.

At http://www.bba-reman.com/forums/topic80020.aspx they seem to be handling the same problem.

Have a look at the following document: http://citroeny.cz/navody/c5/System_Bos ... cky%20.pdf (Yes, it says "Citroen" but it is basically the same as in the Peugeot.)

Look at page 9 (page 19 of the pdf document). The parts you might want to check are "8. Turbocharging pressure regulation electrovalve" and "10. Variable geometry turbo control diaphragm"

You might also want to have a look at page 17 (page 27 of the pdf document). In that diagram those parts are 8 resp. 11.

An electical signal is operating it to open a vacuum toward the wastegate. Check if the electical signal is coming through. Check if there is enough vacuum to operate the wastegate. I think PP2000 offers the ability to test this electrical / vacuum actuator circuit.

When you do the checking, you might want to unplug the vacuum pipe that goes into "9. Recycling regulation electrovalve (EGR)" (ref. 4 in page 27). Plug a tight fitting screw or bolt in the dangling tube to prevent the vacuum from leaking. No vacuum is no brakes! The engine will run fine without this EGR valve being operated, there will be no engine malfuntion indicator or message on the display.

The electrical valves are on the bulkhead. There are 2 or three of them, depending on your model. See viewtopic.php?f=1&t=21522#p216719 which explains it all.

Any progress?

You might want to have a look here: http://www.406coupeclub.org/PHPBB3/view ... 29#p528029

When I had exactly the same issue, it was the turbo vane being stuck due to deposits. Easy to diagnose, easy to fix. I do it every year now.

Seems to be a quite related issue.

Nothing yet... this last month, it's been hard enough to catch time to 'breathe'.
I should have a few days off coming so I can replace the MAF sensor and check the electro valves on the bulkhead.

As for checking the turbo vanes for deposit, I think only the turbos on the 2.2HDi are variable geometry. Plus, this turbo's been R&R'd (Removed and Rebuilt)...

Thanks, and cheers

ShadowStripes wrote:As for checking the turbo vanes for deposit, I think only the turbos on the 2.2HDi are variable geometry.

Yep.... i'm sorry, just missed that one here. At least one thing less to check

Cheers, and good luck finding time to breathe!