Macchiman

A wiring diagram may help, I have a multimeter. How can I check if the fan is controlled by the ECU or its own circuit?  I had the engine upgraded to Jenveys and a new MBE 9A4B ECU some years ago.

The car, 2007 Sigma 1.6 SV,  has been having intermittent overheating issues.  The cooling fan sometimes kicks in and sometimes doesn't.  I have changed the fan relay, but still having issues.  I guess it must be the coolant temp sensor, which seems to be located at the rear of the block underneath the coil pack.  Is this correct?  Any thoughts on the issue?  Thanks.

A good friend has 4 tickets for Goodwood Revival 2021 Saturday 18 Sept.  Inconveniently they now have to go to sisters wedding on the same day.  For sale at face value of £320 for the four, plus postage.

I fitted my 155 hp Sigma SV with the Dunlop Bluresponse in May 2018 and have done around 4000 miles without any problem.  This includes a two week blat around the Black Forest and various Alpine passes this year.  Air temperatures in the mid 30's and I had no problem in the curves, unlike some of the Porkers trying to keep up .  They have also been good in the wet.  Great all round tyre, but definitely not as sticky as A021's.

MBE 36L038A  ECU as fitted to my 2007 1.6 Sigma Supertsport SV.  The ECU has been remapped by the two Steves at Track’n’Road to improve the standard Caterham map.  Smoother power delivery, flatter torque curve.

I now have TBs fitted and new ECU, so the original is surplus to requirements.

£180.00 plus postage

Peter

Is this still available?

The lead to the lambda sensor is OK.  Well secured and not fried.  The original sensor was marked Ford, but was made by Bosch and had a Bosch number  0258 006 599/600.  I spoke with the Technical Dept at Bosch, and they said that part number was deleted in 2016 and the direct replacement was 0258 006 605.  After fitting I disconnected the battery, and then re-connected to see if it would "re-set" the ecu.

If I purchased the MBE lead, would that  allow an auto electrician to use standard diagnostic kit?

I’m having a problem with my 2007 140 SV.  Was going great, but suddenly became very lumpy, though not missing.  A trawl through past postings suggested Lambda probe.  I disconnected it and engine back to normal!  Noted part number and got a replacement Bosch part from on-line supplier.  Fitted it and now back to very lumpy engine.  Took to local garage to see if their diagnostics kit would identify the problem.  They could not get any readout from the diagnostic port.  Car is fitted with MBE 36L038A ECU.

I know that It’s not possible to access the mapping, but should it be possible to get a diagnostic readout?

Thanks

Peter

Oxted Half Hood.  Bought 5 years ago and used on my 1998 Series 3 with Caterham standard “thin” roll bar.  It fitted OK, with the tensioning straps fully pulled up.  Later used on my 2010 Series 3 with Caterham standard “thick” roll bar. It also fitted this OK with the tensioning straps being just about long enough. It will not fit FIA roll bar.   Very good condition.  

I will also include a lightweight shower cap made by “Bespoke Sevens” About 5 years old, the elastic straps a little saggy.  

 £98.00 including postage for both.  Do not want to split

I now have a SV, so no longer required. 

Around 2:30 spotted going up through Hope Ranch.  15 mins later came past me in Los Positas Road.  I was the overweight guy on a push bike, sweating profusely.  If you see this, drop me a pm, I'm in SB for a couple more weeks and it would be good to exchange notes over a beer. 

Oil pressure sender is still disconnected.

Ref the speed sensor, I'm at a bit of a loss trying to understand the wiring diagram, and don't feel that I could identify the correct wire and then disconnect it at the ECU

Should I disconnect the variuos instruments behind the dash and/or at the senders?

I think I've reached the point where I have to involve a specialist.  Any pointers that I can pass on would be very useful.

Thanks, Peter

Well, I spoke too soon!  Went out for a test blat, ran for around 15 mins, then instrument fuse blown.  Replace, and it ran for about 5 mins, blew, replaced, ran for another 5 mins and got me back home, fuse still OK.  Left ticking over in drive for 15 mins, still OK.  I think it's time to call an auto electrician.........

Must be the sender, as it is disconnected at the engine block.  Wiring and gauge all still in place.

Peter

Thanks DJ.

Disconnected oil presure sender, started engine and it ran until I switched it off!

Restarted a couple of times at let it idle until fan cut in.  No problem.

I haven't been for a run yet, but looking good!

Thanks to everyone, and something to remember if your Sigma blows the instrument fuse.

Peter

Jonathan, the current situation is:

The engine stops because the instrument fuse blows.

It was suggested that a fault in the sensor wiring, from multi pin plug to the wheel sensor, may be the cause.  I have disconnected the sensor at the multi pin plug, and replaced instrument fuse.

On switching on the ignition (with speedo sensor still disconnected) all guages respond, and ignition warning light is shown.  Engine will crank, start and run for approx 30 seconds before stopping with a blown instrument fuse.  Therefore it can not be the sensor causing the problem AFAIK.......

I originally reported that some time before the continental breakdown, that the oil pressure gauge had gone full scale, and I am now wondering if the fact that the engine runs for 30 seconds before blowing the fuse may be something to do with the buildup of oil pressure on startup causing faulty oil pressure sender to blow the fuse.  

I will disconnect the oil pressure sender but can not identify it on the engine block, build manual refers to  "Connect the black wire from the vehicle loom to the oil pressure sender on the LH side of the engine block."

Thanks

Peter

Yes it is, but I have now disconnected the sensor at the multi plug connector, and replaced the fuse.  Engine started, ran for 30 seconds then blew fuse again, so it can't be the sensor. 

I suppose there could be a short somewhere in the wiring loom supplying the sensor, or something completely different............

Car is finally back in my garage.  It's a long story, but better late than never!

Checked the speedo sensor wiring and no obvious sign of insulation being worn away on the flimsy wire from the multipin  plug down to the sensor.

Gary7 mentioned that his sensor also looked OK but had an internal short.  Is there anyway to test this before coughing up £66?  There are brown, black and blue wires from the sensor.

Thanks 

Peter

Thanks for all the info and suggestions.  Looks like the speedo is no. 1 suspect.  I'll report back my findings once the car is returned.

Thanks again

Peter

Thanks for the suggestions.  I have a copy of the assembly guide and owners hand book, and a multimeter, though I'm not too good at deciphering the wiring diagram.  Once I've got the car back I'll check the speedo sensor cable. 

Johnathan, are you saying that it is unlikely that the oil pressure gauge and sensor are the cause the problem?

On my return journey from Italy after an uneventful 10 day trip through the Ardennes, Black Forest and various Alpine passes, I had the rather uncomfortable experience of my engine loosing all power whilst trying to avoid the 150 mph rocket ships in the outside lane of a German autobahn.

Around 30 mins before the loss of power, I noticed that the oil pressure gauge was reading full scale (8 bar).  The water temp was normal and the engine was running as normal, so I assumed that there was a fault with the gauge.  Approx 30 mins later the engine died.  I managed to coast onto the hard shoulder without loss of life (mine). 

Car is a 2010 1.6 Sigma 140bhp

Do the POBC have any suggestions how to identify and fix?  And why does an instrument malfunction kill the engine?

Thanks

Peter

That makes sense as I think my 7 started life as an Acadamy model.  Looks like a job for the weekend.

Thanks, Peter

That makes sense as I think my 7 started life as an Acadamy model.  Looks like a job for the weekend.

Thanks, Peter

Yes, that's the one.  Mine is in the lower  mounting bush.

Just rejoined the club after a gap of a few years and notice that there have been some changes to the web site / forum.  From what I read, it looks like the jury is still out on the new look..........

Checking over my recently acquired Sigma engined Supersport, I noticed that the forward link arm is in the lower position, whereas my old 7 and the build manual have the link arm in the upper mounting position.

What difference do the alternative positions make?  Comfort takes precedence over ultimate handling at my age.