Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Search Today's Posts Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 20th March 2021, 10:17   #1
PaulE
Regular poster
 
MG ZT 135+ (04), MG ZT-T (06), Rover 75 (01)

Join Date: Jul 2012
Location: London
Posts: 58
Thanks: 7
Thanked 7 Times in 4 Posts
Default MG ZT 2004 Facelift Diesel not starting. Help Please!

Hi Everyone.

It's been a little while since I've been on here as our MG ZT and Rover 75 fleet have been almost bullet proof! However, we have run into a problem and I'd like to try everything before giving up on the car...

I've tried to lay out the information in an honest way. I have had some experience with the diesels, but this has me a little perplexed..

Current situation:

Car does crank, but does not start.
It doesn't sound as if fuel is getting in. I say this because there is a clean cranking sound but no attempts or struggles to fire.


The checklist on the forum:

The plenum area around the ECU was part filled with water to below ECU (slapped wrists). That has been cleared. ECU was dry, but I left the ECU in the air for a week. But everything else in the car appeared Fine prior to this and no change now.

Checked fuses.

TOAF can connect to ECU and car.

TOAF reported immobiliser error on clearing the codes, but the glow light alert comes on and the engine tries to crank. I have removed the chip from the key and of course it doesnt even try to crank. returning the chip returns expected functionality, with the exception of starting.

I have removed and fully charged the battery. No difference.

I have checked the pump in the boot. I can hear it running - it was replaced about 4 years ago.

I can hear a clean pump sound near the high pressure pump area. This was also replaced about 4 years ago

The car does not start on Easy Start. It sometimes catches but does not idle (as in, it stalls)...

Serious Injector Leakback - I have tested for leakback with a proper set I have. No leakback on any injector noted.

Not done:

Fuel Pressure Sensor - Replace
Cam and Crank sensor -

Not yet changed this - is there any likelyhood this would cause the symptoms described above? I have a donor car that works perfectly.


Also not checked:

Serious High Pressure Control Valve Regulator Seal -

ECU / ECU Capacitors - Replacement ECU and a session on T4.


History that got us here:

Car drove erratically. MAF sensor and MAF sensor connector failure. Removed connector and seemed to resolve whilst waiting for a new sensor and connector.

Not starting in cold weather. Noted glow plug error. But then non starting occurred when warm. A few turns of the keys resolved. This no longer helps and no attempt to fire during cranking.

Other notes: Fuel tank is full and we don't drop it below half on any of our diesels.


So what should I do next?

Thanks,

Paul.
PaulE is offline   Reply With Quote
Old 20th March 2021, 10:51   #2
Atlan
Avid contributor
 
rover 75

Join Date: May 2016
Location: Home
Posts: 129
Thanks: 4
Thanked 50 Times in 43 Posts
Default

Try here.
https://www.the75andztclub.co.uk/for...ad.php?t=22402
__________________
Illegitimi non carborundum
Atlan is offline   Reply With Quote
Old 20th March 2021, 10:51   #3
Arctic
Give to Learn
 
Arctic's Avatar
 
Rover 75 Tourer

Join Date: Aug 2010
Location: West Midlands
Posts: 15,405
Thanks: 874
Thanked 4,987 Times in 3,001 Posts
Default

Hi Paul.
I would say the ECU as been for a swim, and being that you have an 04 plate i presume there is no UBP.

When was the fuel filter last changed? also for the sake of 5 i would check the regulator O-rings.

Check the oil light comes on as it should with key to position II? If not you have a faulty ECM
__________________
Arctic
Givology Learn to Give
Everything is Achievable

ad altiora tendo.

Check out the 2020 meet dates
http://www.midlandsnanomeets.co.uk/meets_2014.html

http://www.the75andztclub.co.uk/index.php?thepage=howto

" You do the work , we supply the expertise "

Last edited by Arctic; 20th March 2021 at 10:55..
Arctic is offline   Reply With Quote
Old 20th March 2021, 13:28   #4
PaulE
Regular poster
 
MG ZT 135+ (04), MG ZT-T (06), Rover 75 (01)

Join Date: Jul 2012
Location: London
Posts: 58
Thanks: 7
Thanked 7 Times in 4 Posts
Smile

Thanks for the help so far.

Re starting problems sticky, thanks. That's the one I've started to work through.

The oil light does come on when I turn the ignition to Ii.

Although the plenum compartment had where in it, it was below ecu, and no marks on the ecu body to suggest water that high.

I should also mention I have checked the inertia / impact fuel cutoff switch. Seemingly no problems there.

Is there anything I can check out in Toaf?

I'll take a look at the seals as mentioned.

Thanks for the support so far!

Paul.
PaulE is offline   Reply With Quote
Old 5th April 2021, 12:45   #5
PaulE
Regular poster
 
MG ZT 135+ (04), MG ZT-T (06), Rover 75 (01)

Join Date: Jul 2012
Location: London
Posts: 58
Thanks: 7
Thanked 7 Times in 4 Posts
Red face We now know the ECU has been under water...

I'm still trying to save this MG ZT whilst still viable.. Appreciate any help / suggestion at this stage to save the car!


I have now made a YouTube video showing the condition of the ECU, attempted starting and attempted starting with easy start, along with TOAF readouts.

Video here:
https://youtu.be/k2dvIdLi30A


Upon further investigation, it appears that the Plenum had been blocked for a while and part filled with water. (Slapped wrists, it was cleaned out a year ago, but has been parked under trees over a wet year..!)

The glow plug relay was badly corroded and inoperable. This has now been replaced. No change when attempting to start the car.

The ECU had been partly under water. Although the car had been starting and driving in that condition I removed the ECU from its housing in an anti-static environment, and cleaned off Water corrosion. It appeared the lower third had become dipped, particularly when going round corners. I've attached some high res pics of the front and back of the ECU in its current state.

Referring to : https://www.the75andztclub.co.uk/for...splay.php?f=11
B) Check your plenum drain
There will likely be a host of other symptoms available to confirm that your ECU is playing up such as erratic dials, malfunctioning electrics.
There are no other apparent symptoms Dials all operate as expected and hadnt shown any issues. Electrics all seemed function perfectly. TOAF managed to talk to and configure ECU.

Back to the mechanics:
The fuel filter, oil filter and oil had all been changed within the last few months in a service - Although we decided not change the pollen filter, hence not noticing the build-up of dirt in the plenum water runoff.

Looking at low pressure side fuel flow, we removed the fuel connector both sides of the filter and there is good flow. The In-tank fuel pump does not seem to struggle in flow or sound.
The high pressure pump was replaced a few years back, and sounds OK. I have not tried opening the high pressure common rail to check we actually have pressure there.


Given the sounds (see video) Our current thought is there is no fuel getting into the engine - the sound with / without easy start seems to suggest that, plus the lack of diesel smell at the exhaust.

We're exploring the idea that parts of the ECU may be misbehaving as a result of its recent swimming lessons..?

Is there any information on how to safely measure the signals at the injectors with an oscilloscope? I will have a read through the forum, but if anyone knows or has a link, that would be greatly appreciated. It would be useful to know if the ECU is not reading data or controlling IO properly. E.g. TOAF comms OK, some starting actions seem OK, but has some IO function to sensor / injectors failed?

An EWS Immobiliser fault registers under TOAF as shown, but the immobiliser is allowing starting. I did remove the chip from the key and try starting, and the immobiliser appeared to function as expected, not even a cranking sound. Returning the chip returned cranking as expected. What might cause that?

The temperature sensor was replaced and the temperature showing correctly in dash a few months ago. But the temperature sensor error is confusing - is the ECU not seeing or reacting to that hence the TOAF error?

I do have some electronics experience and test equipment and would rather not just write off the ECU - it would be very useful to know if there is damage and what that manifests in, and if it is repairable. If there are a stock of new unprogrammed 75 / ZT ECUs, what is the going rate of supply and code?


Would a T4 session provide more insight into wellbeing of the ECU? We are in the Buckinghamshire area.


On another note, I do have a Rover 75 diesel we can borrow parts from. The engine works beautifully in it, but sadly that car suffered severe internal rot to the upholstery before I received it and rust in the sills. It has been useful maintaining our other 4 Rover / MGs as a donor. Its sat there for a year and a half and a quick flip of the key and it started . But it's sadly no longer viable as a road car. We used this as the donor for the glow plug relay, for instance.


Although I've put the screengrabs in the video, here's the TOAF readout:


===
TOAF Readout after clearing errors but before turning over:


0100 - air mass meter
0110 - temperature sensor


Expanding the 0100 - Air Mass Meter:

Errors count 3
Sporadic error

Error 1
Engine speed : 0.00 1/min
Engine coolant temperature : 10.86 c
Injection volume 26.63 mm3
Rail Pressure : 0.0 bar
Current odometer : 331550 km

Error 2
Engine speed : 0.00 1/min
Engine coolant temperature : 8.81 c
Injection volume 28.67 mm3
Rail Pressure : 0.0 bar
Current odometer : 331550 km






3505 Glow Device.

==================
After turning the car over, as per video, the following error added:

1DF5 - Electronic car immobilisation system (EWS)

Errors count 1
Error Present
Error 1
Engine speed : 0.00 1/min
Engine coolant temperature : 14.95 c
Injection volume 23.55 mm3
Rail Pressure : 12.05 bar
Current odometer : 331550 km

=====

I have checked each of the points in the non-starting guide:

A How much fuel do I have?
Top quarter (see video). No variation on performance if tank if full or part full. We dont run our diesels below bottom quarter.
You should be able to hear the rear pump making a high pitch whine by listening to the rear wheel arch or pressing your ear to the rear seat base. If still unsure, remove the rear seat and feel the access panel for vibration. This will indicate that the pump is working.
We can hear this. Sounds fine.

B) Check your plenum drain. There will likely be a host of other symptoms available to confirm that your ECU is playing up such as eratic dials, malfunctioning electrics.
Half filled with water. Drained and left for two weeks.

C) Start the car with Easy Start
ii) If the car does not start on ES
Battery fully charged.
Synergy Box not fitted.


Ill try these things next:
Fuel Pressure Sensor Replace
Cam and Crank sensor

And then will look costs for:
Serious High Pressure Control Valve Regulator Seal .
ECU / ECU Capacitors - Replacement ECU and a session on T4.




Any help appreciated, I would dearly love not to scrap the car, we have a bit of a history and has very recently had a new complete clutch and tyres! When it drives, its really quite punchy and fun, so worth saving if possible

I also promise to come back to the forum with the resolution / outcome.

Thanks,

Paul.
PaulE is offline   Reply With Quote
Old 5th April 2021, 13:14   #6
PaulE
Regular poster
 
MG ZT 135+ (04), MG ZT-T (06), Rover 75 (01)

Join Date: Jul 2012
Location: London
Posts: 58
Thanks: 7
Thanked 7 Times in 4 Posts
Red face High res pictures of water damage o

High res Photos of water damage to MG ZT Diesel ECU bay:
I have compressed these images from the original 32mb files The lighting wasn't great, so I'll try to get better pictures if useful later.

The car:


The rusty Glow plug relay from ECU enclosure

The back of the rusty Glow Plug Relay and the replacement:

MG ZT Diesel - ECU, front.

MG ZT Diesel - ECU, back.

Last edited by PaulE; 5th April 2021 at 13:19..
PaulE is offline   Reply With Quote
Old 5th April 2021, 14:25   #7
75driver
Posted a thing or two
 
75driver's Avatar
 
Rover 75 saloon, manual. Rover 75 Tourer, Auto.

Join Date: Jan 2013
Location: Newry
Posts: 1,600
Thanks: 509
Thanked 391 Times in 328 Posts
Default

Might be worth reading post no 7 on this thread

Quick ECU question
https://r.tapatalk.com/shareLink/top...ink_source=app

I had a non start on a diesel auto recently, (EP error displayed on IPK) and changing relay no 4 in the engine bay fuse box got me running.

Might not be related to your issues, but easy to check by swapping relay 2 and relay 4.


Sent from my iPhone using Tapatalk
__________________
2006 75 Contemporary SE diesel manual (#1)

2003 75T Connoisseur SE diesel auto (For Comfort)
2005 75 Connoisseur SE diesel auto (Marmite duotone )
2006 75 Connoisseur SE diesel auto (The last one?)

2009 E220 (For a change)
2018 L200 (For Big & Heavy Things)
1976 W114 250 Manual (For Sundays)
75driver is offline   Reply With Quote
Old 5th April 2021, 16:54   #8
trikey
Premium Trader
 
trikey's Avatar
 
T4

Join Date: Nov 2010
Location: Norfolk
Posts: 29,729
Thanks: 7,366
Thanked 11,772 Times in 6,842 Posts
Default

That ecu looks goosed to me!
__________________
Lest we forget..
trikey is offline   Reply With Quote
The Following User Says Thank You to trikey For This Useful Post:
Old 5th April 2021, 19:17   #9
Atlan
Avid contributor
 
rover 75

Join Date: May 2016
Location: Home
Posts: 129
Thanks: 4
Thanked 50 Times in 43 Posts
Default

Do you also have an electrical fault with the injector loom? Check circled area at 3.01 in video clip.
Attached Images
File Type: jpg Bay.jpg (72.1 KB, 12 views)
__________________
Illegitimi non carborundum
Atlan is offline   Reply With Quote
Old 5th April 2021, 19:40   #10
BigRuss
Premium Trader
 
BigRuss's Avatar
 
75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4)

Join Date: Jul 2007
Location: Liversedge, West Yorkshire
Posts: 5,106
Thanks: 886
Thanked 1,111 Times in 545 Posts
Default

There's no way it's going to reliably start with that ECU

That's been wet for quite some time. It may repair, but it depends on if any damage has been caused by the water shorting the components but will certainly need testing.
If you wish I could have a look at it for you, I do have replacement ECU's should it be beyond repair



Russ
__________________


Replacement Key Service
BigRuss's Replacement Key Prices

Full T4 Testbook diagnostics available.
Diesel ECU repair and replacement.
Options enabled or disabled as required.
Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160
MG 160 V6 to 177 upgrades available
P.M. for details.
BigRuss is offline   Reply With Quote
The Following User Says Thank You to BigRuss For This Useful Post:
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 15:29.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Copyright 2006-2020, The Rover 75 & MG ZT Owners Club Ltd