AndyW

You can check resistance across the terminals of the sensor with the plug disconnected. To check the voltage with it connected you can sometimes get a thin probe into the wire entry point of the connector to reach the metal terminal. If not, in the past Ive pushed a needle through the wire insulation which is better than cutting it.

Al forwarded me your MEMS logfile to look at, and I agree with his comments. As we've mentioned before, you've got something wrong with your air temp sensor as it's showing a fault code. But very oddly it seems to be producing inverted values, starting with high temps and getting cooler as the engine warms. Either the sensor is duff or it's the wrong type, or it's connected wrongly. Did you make the checks I suggested previously? Disconnect the multiplug and check the resistance across the sensor pins - it should be about 2400 ohms at temp 20 deg C (range from the manual is 5700 ohms at 0 deg and 1100 ohms at 40 deg C). Also, with multiplug connected and ignition on, check the voltage the sensor is providing to the ECU - at 10 deg C temp, the green/black wire (to ECU pin 16) should show about 2.8 volts, and the pink/black wire (to ECU pin 30) should show an earth. Also as Al says, your battery voltage looks very odd, and I wonder if this is the root cause of your issues. The alternator output when running isn't high enough, as it should be in the region of 13.4-13.7 v, but yours is mostly 13v and below. Also it doesn't look very steady or consistent, whereas mine stays 13.5v +/- 0.1v for the whole of a journey until turning off when mine drops to battery voltage about 12.4v. The end of your log shows the battery voltage gradually tailing off down to 11.5 v over a minute which is not normal behaviour. It's as though your battery isn't holding voltage, or the alternator output is declining. Engine voltage is critical to many MEMS functions, including air flow calculations, stepper motor control and resetting it after stopping, and coil output. I just wonder if this is the cause of the problems you are seeing. If the voltage is declining after driving for a while maybe the ECU can't function properly and is shutting down? I would get your alternator and battery checked, as well as the wiring between them and all their earth points. Cheers, Andy

Sorry Al, cant make that Sunday this year. Daughter is running a half marathon in Oxford.

Hi Al, sorry I can't make this weekend either, much as I'd like a run out. Cheers, Andy

Thanks Dave & cb750. It looks as though midi and mega fuses are much the same thing, except megafuses are larger and go to higher amperages. Ill go for a 60 amp midi fuse and holder. Hope thatll be high enough to protect all the circuits.

Thanks Bob. Fusible link cables don't seem to be available now, apart from scrappies, so I wondered what current practice was. Anyone know if midi fuses serve the same purpose?

A question for the electrical experts, as I'm about to do some work on my Superspec wiring to sort out the rat's next of cabling and add extra fuses and relays. Looking at wiring diagrams in various Haynes manuals, I noticed that many older cars seem to have a fusible link between the battery and the rest of the permanent live circuits, with something like a 60 amp rating. Presumably this gives some protection for the alternator circuit and the wiring upstream of the normal fuses. Is it worth adding something like that while I'm redoing my loom? And if so, are fusible links still used in modern cars, or what's the recommended alternative nowadays? Andy

Slight correction - it's the Halfords Autocentres that do battery tests, not the normal shops. I removed the battery from my car and took it in separately, where they put it on a test machine and gave me a performance printout. I presume you could just drive in and they'd have to remove the battery from your car to test it. BTW, they will advise and quote on a replacement if needed, but no obligation to buy.

It would be worth having the battery tested. I had similar problems with my Superspec for a couple of years. It would crank and start fine from cold, but when hot the starter motor would barely crank or just click. Went through all sorts of fixes with thicker battery cables and thinking the starter motor was overheating. But in the end I had the battery tested (free at Halfords) and found it only had half the cranking amps. A replacement solved all my problems.

Hi Steve, You may recall I had to replace both belts on my Rover engine a couple of years ago (long story but broken shock absorber > flying spring hat > cut auxiliary belt > jammed around crank pulley > seized engine > snapped cam belt !!) My car had been on the road for 8 years, although only done 3k miles, but the actual condition of both belts was ok. None of the cracking as seen in the photo above. Parts I used for the rebuild were: Cam belt - ContiTech CT803 (Eurocarparts p/n 325770465) Alternator drive belt - ribbed 1152mm long. Rover PQS101590 (Rimmers) (Eurocarparts equiv p/n 202660085 Some Rover engines have a different alternator position, so it might be worth checking if the aux belt run and length is the same for both. Im not sure. My alternator is at top above the water pump. Andy

That long L shaped bracket is correct for Superspecs. It holds the adjusters for the handbrake cables and also goes across the car to give a strong mounting points for the rear seat bolts. Mine is exactly like that and has passed SVA and all subsequent MOTs without a comment. However it is low to the ground and often catches on garage ramps. Some people have mount the L the other way up so the upright is upwards.

The previous owner of my Superspec had the nearside wishbones replaced. They were only in steel not the gold passivated finish of the originals.

I believe that GBS took over the jigs from Robin Hood and can make up wishbones to special order.

The rubber block inside the square bracket is supposedly an engine mount from a Fiesta Mk 3. Quinton Hazell EM4063.

It’s a photo from last year when I had to remove the radiator to get at the front engine mount. The L shaped plate that goes over the cross tube had cracked so I had a new bracket made and welded on.