Technical Td125...

[rattlysmarea]

Hi all,
I have a problem with my 2.4 Marea 125TD the turbo works intermitantly, i`ve checked the obvious hoses and connections but nothing is obviously wrong..i`m thinking EGR valve?...anyone had similar or got any ideas...i have had the car "scanned" but two different types of software could not access it!!
Cheers
rattly

 

[EI4GGB]

what exactly do you mean by intermittently ? Does the power surge and drop off suddenly or slowly while accelerating, or does it work ok some days and not others ?. quick check for the EGR is to disconnect the actuator pipe from the EGR valve and block it off with something..

Owen.

 

[rattlysmarea]

Thanks m8, i`ll try the egr valve thing, sometimes it works and sometimes it dosen`t! Cheers, rattly

 

[Malc]

Hi, we may have similar problem here. I've not had the Marea all that long but have been suffering under power issue. Briefly, when purchased car from friend who'd had it from new, he told me turbo wasn't working. After a bit of forum reading etc. I cleaned the MAF which I thought had resolved problem, but as in earlier post today it's still intermitant.

Just unplugging and reconnecting MAF connector improves it until next time it goes. I cleaned the EGR when I cleaned the MAF originally but I wouldn't have thought this to be the cause - maybe wrong. I'd be really interested in your findings, please read my posts to confirm that we have similar if not same issue.

Malcolm

 

[rattlysmarea]

Hi Malc,
Did the MAF thing (cleaned it out and re-connected etc) today, had a turbo for about 200yds,then back to square one!! Ran it home tonight (16 miles) with EGR valve disconnected and vacumn hose blocked, first mile was ish!!, next 12 miles was flat as a t**d, last few miles it went like a rocket!!!....but it does seem to be a bit better if you let the power build up slowly, prob cuz your not relying on the turbo then..???
Any views welcome, i`m stumped!!!
Also sometimes the management light is on and the turbo is working, another time it will be off, the same when its not working!!
Cheers,
rattly

 

[Malc]

Hi, I've ordered a new Bosch MAF from air mass meters. I've been searching around for what I can find re MAFs and from reading a Rover forum, there are lots of people disappointed with the Bosch MAFs only lasting between 30 - 40k miles before going out of spec. Pierburg seems preferable for reliability but I don't think they do one for the Marea, at least that's what I'm told. (There was also talk of someone having developed a MAFAM - MAF amplifier as a cheaper method than MAF replacement and it may have been variable to enhance performance.)

The main symptoms being low power upto 2.5k rpm and not going up those hills it used to fly up, not that I can make that comparison as I've not had it so long, but in comparison with my Xantia with bhp/hp of 66/90 compared with the Fiat's 91 /125, the Xantia pulls better at lower revs up a good gradient.

Anyway, should have delivery by Friday so I'll let you know how it goes. I'm working the weekend and with these dark nights it may be Monday before I get a chance to change it.

Malc

 

[Malc]

Changed the MAF with some improvement but car still not wanting to accelerate away from 60 - 70mph.
Took car in to 'Turin Motors' Fiat / Alfa specialists in Leeds today for diagnostic check, explaining my problems and actions taken so far.

Went to pick her up - There's a slim chance that a new EGR may resolve issue but it's the ECU that is faulty from diags run. Didn't have a print out as printer not working. They don't recommend changing ECU as 'not worth it @ £1k+'.

Questioning changing ECU with a second hand one, I was told it wasn't so simple - key ECU etc also req'd.

So Rattly, this seems to be ECU at fault, or have you found anything different out?

Malcolm

 

[rattlysmarea]

Hi,
Put a new air flow meter on a few days ago and it made an immediate difference, went like an absolute rocket!!..sorted or so i thought after a few days i started getting the odd loss of power did a long run in it yesterday and turbo prob only worked 50% of the time!!...
If its the ECU then yep it`s DEAD!!!!
The MAF has made a difference and the turbo is still working a lot more than it used to...but it still ain`t right!

 

[Malc]

They said that the failing EGR had caused the ECU to fail - beats me how they work that one out, it's only a vacuum valve - a receiver, but one of their guys was in a main dealers and remembers some bulletin stating this.

I'm really sick! When I first got it with no power, and as you have experienced, seemed to make significant improvement, I thought I'd cracked it. I decided to get cambelt done, towing attachment, new front tyres for MOT etc. What was, as I thought, a bargin find has cost me dearly to be left with a problem car.

Keep me posted if anything else comes to light. I just can't believe that such a failure can happen on a 40k car.

Malc

 

[EI4GGB]

interesting..

what exactly did they say was wrong with the ECU ?, I know they didnt give you a printout but what fault codes came up ?

 

[Malc]

A faulty ECU caused by the EGR not working correctly. Other than one of his guys having read some bulletin on that he couldn't explain why a vacuum operated valve could 'knack' the ECU. That's the thing that hit me after leaving garage - they didn't even mention any fault codes. I had a 'USBdongle' on my key fob so should have asked for a copy off their PC.

I specifically asked if they had the right diags equip't for the '98 Marea
prior to booking it in, as I understand that this is prior to common protocol etc.



As I say, I'm a little sceptical about their diags - ECU faulty but a new EGR might improve it. How's that work then? - There's a slim chance it may improve things.


I'll get up their on Tuesday and see if I can get any more out of them.
Thanks
Malc

 

[rattlysmarea]

Hi,
Deffo not gonna give up on this, i too have just done cambelt, aux belt idler, tyres,brakes etc as it seemed like the MAF had done the job!!
I`ve got the latest Smap On diagnostic softcare but it wouldn`t access it, i also had another specialist auto electrician look at it but he couldn`t get into it either, but said MAF or slim chance EGR. I have one more auto electrician who said that the old Sykes Picavant system was quite good on Fiats at that time and he would dig his old kit out from the loft if i wanted, i`ll give him a call tomorrow and see what happens!!
We also now have another customer at my garage with excactly the same fault!
Cheers,
Roy..Sherborne

 

[Malc]

I've just been and picked up the EGR. I asked them for codes, but he said that it was coming back as an ECU error, no printer working as earlier stated. He did say that the cleaning of the EGR which I did early doors had improved things, NOT cleaning the MAF as I had been thinking. Why did I do both at the same time?

I'm sure the vacuum on the car far exceeds the one from my mouth. (Very careful how I put that). Having just done this on the new one, it does seem to have opened more easily (less resistance) than the original. Also the valve closes completely where the original one tends to sit a little 'off set' so you can easily see light through between the valve and seat.

I am staight out after work tonight and wont be home 'til 22:00 so I doubt that I'll get it changed tonight... but can I resist? Anyway I'll give you feedback as soon as I do and had a drive. The specialist was adamant that my problem was down to EGR not MAF and he also wants feedback.

Roy, it'll be interesting for you not to touch anything other than the EGR on your customer's vehicle to confirm this diagnosis.

Speak soon - Malc

 

[Malc]

Hold fire from changing that EGR.

I changed the EGR valve last night and have just nipped out of work to take car in for ECU reset as they said they would.

Dealt directly with the mechanic this time, in garage when he opened the lid. He was surprised that the EGR had been changed and not the modulator valve - the bit on the bulk-head that controls vacuum to EGR. - Explains my earlier question to guy in office as to how the mechanical EGR can mess your ECU up.

So potential damage to ECU would be from persistant over demand attempts to operate failed modulator valve.

So how much is a modulator valve? As I had to dash back to work, I'm now awaiting a phone call. I don't suppose there's an alternate supplier other than Fiat?

 

[EI4GGB]

unless the modulator valve developed shorted turns - I dont think the ECU would be damaged by trying opening EGR all the time as it has no feedback from the EGR - it never knows how much it is open, it just drives it according to the map. it might be possible to repair the ECU internally, but thats an electronics job..

 

[Malc]

That was the feedback from mechanic with previous Fiat main dealer experience. The modulator was the problem, but just depended on how long fault had existed as to wether ECU may have sustained damage to the components driving the Mod. Valve i.e. overworked. He said some ECUs were OK when MV changed, just how long MV had ben faulty.

Malc

 

[Kev_marea]

Just a thought, could you guys look at your air ducting after the MAF and look for splits / holes in the 'corregated' section. I have a hole in my pipe there, just before the turbo, I intend to replace it eventually, it's not causing me any bother really, but it must be affecting the running performance somehow.

 

[Malc]

This saga continues. I don't know if rattlysmarea - Roy has made any progress on his issue but I'm pursuing something that sounds familiar and thought it worth sharing.

Bosch 0 281 diesel series fitted to many VW, Audi, GM, & Ford applications is prone to ECU causing lack of power. This came from www.bba-reman.com

Anyone expand on this one. Does anyone have any experience of this company?

Malc

 

[EI4GGB]

those VAG ECU's are EDC15 ecu's, unrelated to the TD100 (its a Lucas). it might be possible to replace the driver IC inside to clear the fault code and get it working - but you'd be better to get one from a scrappy's or ask for one on the forum. Its not immobilised so you should be able to plug it straight in..
BBA reman have existed probably since the dawn of engine managment. They've got a lot of info on their site. never dealt with them though.