R400 K-Series hesitating at low revs, potentially after getting wet.

[Kimble]

Hi All,

I can see there's a lot of posts about with similar symptoms to this but I do think mine is related to the car getting rained on in a big way.  :(

In general, the car feels like it's misfiring or starved at low revs.  There is sometimes a significant lag when accelerating from low in the rev range and it's more jumpy than normal in first/second at low speed.

The car got very wet in one of the downpours recently and the problem seemed to start immediately after that.

Can anyone point me in the right direction of what parts/connections to check?  I haven't had my 7 long so am still finding my way around it.

Cheers,

Neil

[Jonathan Kay]

1 The wells in which the spark plugs sit.

2 The lambda sensor. Experts, please: is this one of the situations in which disconnecting it as a test is a sensible tactic?

Jonathan

 

[Kimble]

Thank you Jonathan.  I'll give both of them a check tomorrow and report back!

[SM25T]

One or two plug wells full of water. Affected cylinders will have cold exhaust primaries when engine is running. Had this on mine after hitting a large flood.

[Kimble]

Ok, took the plugs out, gave all the contacts a clean and put it all back together.  Seems to work fine.

Thank you all!  Great advice.

[Jonathan Kay]

That's encouraging.

Was there any moisture down there?

Jonathan

[Kimble]

Not that I could really see or feel but there was a little bit or arcing on the top of one of the plugs and some white residue on the rubber inserts that made me think water had been ingressed.  I used some WD40 type stuff to try and repel a bit of moisture before refitting.   I did notice one of the plugs was quite oily up at the thread which is maybe an indication of loss of ignition in that cylinder(?).

She felt much more herself when I took for a run out at lunch time.  Just how I remember.

[Jonathan Kay]

Thanks

Jonathan

[rj]

Another issue I've seen is if the mapping connctor gets wet, the ECU may think you've started mapping (!) The engine ran very poorly, but when I connected the mapping lead to ask it why it was unhappy, happiness came back. In other words it seems that the inputs for mapping on the MBE is high impedance, and as such sensitive to moisture.

 

[Kimble]

Resurrecting my old thread here as I still think my K400 has a specific problem around the 3.5 - 4k rev range.

In general, it just seems a bit gutless around that point and I can hear a deeper 'blowy' sound from the exhaust and feel some hesitation in the engine..  If I add more throttle and get through that point the engine picks up and away she goes.

I've checked all the spark plugs and connectors with some liberal use of WD40.  I have also disconnected the lambda sensor and the behaviour was much the same.

It feels like I am going to need to hook this up to easimap or some software to get some better readings.

It's a 2004 R400K with a MEMS box with 'Road' written on it.  My standard ODB2 reader couldn't read anything from the device so I am guessing I need this lead and then I should be able to plug a Windows box with Easimap to read from the MEMS unit.  Is this correct?

https://www.sbdmotorsport.co.uk/MBE-MAP-KIT-3-CAN-basic-can-mapping-kit-for-mbe-can-based-ecus.html

Once again, thank you for all your help.

[SLR No.77]

It's a 2004 R400K with a MEMS box with 'Road' written on it"

"MEMS" is the specific Rover ecu that pre-dates R400 Ks with rollerbarrel throttle bodies, do you mean "MBE"?

Stu.

 

[Kimble]

Yes, sorry.  You are correct MBE.

[John Vine]

Re #10:

Does your car come with a diagnostic plug like this:

You'll need one for the MBE985 connector cable.

JV

[Kimble]

Ok update:

I have the required lead from SBD (They are about 2 minutes up the road from me) and have Easimap installed on my bootcamp'd Macbook Pro.

When I hook the lead up and start the car, Easimap seems to find the interface but doesn't recognise the ECU (the dialog box at the top is Yellow/Black flashing).

I have an MBE Part No 72212, Software 967bc474 (as written on the ECU box).

For anyone with experience with Easimap, is there something that I am missing?

I had assumed I would establish the interface, then I would load a config file that would interpret the data and update the GUI to match it.

Any help appreciated.

-Neil

 

[Kimble]

So from something I've read it looks like 967bc474 isn't compatible with the CAN interface and I need to splice in a serial cable and use a serial to usb cable.  Does anyone have any experience doing this?

[aerobod - near CYYC]

Although it is expensive, SBD have a serial lead, supposedly reading other forums for cars that also use MBE ECUs a standard serial lead will not work or not work reliably: https://www.sbdmotorsport.co.uk/MBE-MAP-LEAD-mapping-lead-for-mbe-serial-based-ecus.html, you could then use a standard serial to USB adapter to attach to the Mac.

[Kimble]

Thank you aerobod, this looks like the right approach.  I think I will go and see SBD again.

[Richard Price]

Kimble,

Do you have a soldering iron? 

If so, the bits to make a coms lead would only cost a few quid!

pinouts here:-

https://www.sbdmotorsport.co.uk/wp/wp/pdf/MBE_Coiled_Mapping_Lead_Pin-out.pdf

You may also have to add three pins to the ECU connector and a short lead with another female 9 way D type connector if it is not already present. 

See ECU pinouts here:-

https://www.sbdmotorsport.co.uk/wp/wp/pdf/MBE967_Pin_Out_Information.pdf

You need pins 6, 14, & 32 (ground, receive, & transmit)

I've had limited success with cheap USB to RS232 converters, but found this StarTech one to work well:-

https://www.ebay.co.uk/itm/111598110253?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

You'll need Easimap release 5:-

https://www.sbdmotorsport.co.uk/easimap%205%20software-easimap-5-software.html

Note:- Easimap 5 is a 32bit program and does not work in 64bit Windows.

 

[Kimble]

Thank you, I should have all I need in a couple of days.  I'll see what easimap says.