turbo pressure measured to high P2045

[sissonk]

This turbo pressure fault is very hard to find. It is an imtermittent fault and I also get P2035 Turbo press. signal short circuit to positive or open circuit , value to high
Is the turbo pressure measured by the map sensor? When this fault is active the car has no power it doesn't matter where you put the pedal to it moves at a very sluggish rate, and then after a while it dissappears. but even then the turbo doesn't kick in like it should , it feels like it is just starting to go and holds that mode until I reach the speed I want. There also is a permanent fault turbo pressure to high. and I can't clear it . I have checked the vac system and found a few leaks fixed those also two leaks in the intercooler piping fixed those. I have also tested the MAP sensor off the car and it seemed ok but I have a new one which will go on when I get some time. Generally I conclude that the ecu can't control the turbo properly it will not kick in properly even though it generates to much pressure .
The Pug. dealer who I got to check it said he say something like this before and it was a broken wire in the harness , I don't like that one. would anyone know where I could get a wiring diagram which would show which plug the wires go in to the ecu , I think it is the middle one but just a guess.
any help appreciated.

[Doggy]

Keith, have you read exboyracer's guide on the coupe forum?

Oh! Anyone else unable to access the coupe forum?

Sounds like you have, anyway the gist of the story is that the vacuum system has to work the turbo actuator to reduce the vacuum, so lack of vaccum / leaks / dodgy solenoid valve etc will all cause it to overboost. (worth checking the vacuum reservoir, attached to the servo on mine, they have been known to split).

Anyways, try this link for electrical schematics: http://www.petrila.net/pug/Service/index.htm (not sure it covers coupes, but the engine electrics at least should match).
Your engine code is 4HX.
Bear in mind the coupe & saloon / estate intercoolers are different and so are the MAP locations, (but not the sensors).

[sissonk]

Hi Doggy:
thanks for your thoughts , yes I have read exboyracer's Hdi guide its a good piece of work very helpful.
and I have checked the entire vac system all the pipes and all the joints and all the valves only thing I didn't ake off the car was the egr and turbo actuators, because of there very difficult to get at. now I have had quite the day I tested the new MAP sensor and compare to the old one and there is a difference the new one doesn't have a limit of output at a pressure that was to low but the new one just keep outputting past the old one. I had already loaded the new s/w what happened was the faults cleared themself but the engine only ran slightly better and then improve abit as I drove. the turbo still didn't kickin properly. So I then cleared the faults and tested it again and it preformed much better turbo nearly kicking in properly . in summary the new s/w and the new MAP sensor work almost right. but then I put the original s/w back on and within a few minutes all the faults were back . so this is very puzzleing why do I get high turbo pressure with original S/W and not with the new ? Does the 180bhp S/W have flat bands as the engine revs there are two in each gear change ? Oh I did also check the vac resevoir it doesn't leak. well I don't understand this yet , any further thought.

[Doggy]

Sounds like you've given it a thorough check over.

Did you measure the vacuum at all? Maybe you have a weak vacuum pump, or something else obscure. Is your brake servo working 100% ?

[sissonk]

ah interesting you mention the brake servo , because everytime the engine fault lite comes on so does the triangle esp abs fault lite. It says something like esp abs system disconnected or turned off and then after awhile of driving it goes away. My earlier thinking was that it must be something to do with the vac system because the brakes where involved . I also removed the two restictions and cleaned them out both were dirty and the brake one was really dirty. I have a gauge , so I will measure the vac level at the vac pump at idle and say 2000 rpm see what I get . do you know what it should be?

[Doggy]

Never done it personally, but I'm sure there's some numbers in exboyracer's missive......

[sissonk]

well checked the vac pressure today and off the pump it was 800 mbar , then checked it at the turbo ev and found it down at 100, so after further checking found that the swirl diaphram is leaking pulling the whole system down . so will get a new one and that should be the end of it , hopefully there isn't something else.
I reloaded the 180 bhp s/w and everything runs much better.

[Doggy]

Well done!

The swirl actuator rod snapped off mine a few years back & it didn't make much difference, (though it wasn't a vacuum leak), so I think you'd get by with it blanked off until convenient to replace.

[sissonk]

great day today , got a new swirl diaphram and fit it , what a job , Pug don't seem to put any design thought into repair or replaceing . I also tried to take off the EGR system but just could not get the two screws out which hold it on. I wonder if it could be got with an impact driver from below ? anyway after fitting everyting back together I tested the vac at the turbo and it was up but only to about -.4 bar which seems to low and everywhere else goes to -.8bar. so I might try changing its source to the swirl feed and give the swirl the turbo feed. Sometime is still wrong as the turbo still doesn't kick in.
how hard is the kick with the 180 bhp remap ? before these problems came up the acceleration was hard and constant 2-4k + rpm.

[Doggy]

great day today , got a new swirl diaphram and fit it , what a job , Pug don't seem to put any design thought into repair or replaceing . I also tried to take off the EGR system but just could not get the two screws out which hold it on. I wonder if it could be got with an impact driver from below ? anyway after fitting everyting back together I tested the vac at the turbo and it was up but only to about -.4 bar which seems to low and everywhere else goes to -.8bar. so I might try changing its source to the swirl feed and give the swirl the turbo feed. Sometime is still wrong as the turbo still doesn't kick in.
how hard is the kick with the 180 bhp remap ? before these problems came up the acceleration was hard and constant 2-4k + rpm.

Changing the swirl flap actuator is awkward, I removed the TPS & its support bracket, which helped a fair bit, also undid the intake pipe work just after the MAF. Never tried to remove the egr.

After remap, there is little if any difference below 2000, but it pulls much harder thereafter, pretty much to the red line.

[sissonk]

thanks Doggy
well got the swirl thingy changed after gouging both hands and removing all the things U mentioned plus a few more, but to my dismay it made little change to the preformance . so I thought it over in my dreams and came up with a good Idea, well actually remembered what exboyracer said to do , that is connect turbo ev direct to vac pump which I did today and yahooo it works . runs smoother , and accelerates oh so nicely. how I love my 406 coupe ..
so the end of a saga , and thanks for all your help Doggy .
My next project is to fit a HHO generator which I bought from USA , this is to get better MPG and also to make sure I get through the NCT or MOT as you call them.
Ill post up the project when I have it working hopefully with some photos.

[Doggy]

Good news!
FWIW no-one has reported any problems passing the UK MOT without the FAP, or even without cat & FAP, like mine. Pretty sure some of your guys have got through the NCT too.