Hot ECU seems to be ok (Erattic starting Meriva update)

In article , T i m writes

It'll be dry joints on the ECU printed circuit board, most likely around the connectors where the various wires plug in. An easy fix if you can wield a soldering iron.

Except I understand some of these ECUs use ceramic PCBs with aluminium tracks and my reasonable soldering skills (BT Electronics tech trained ) will be of no use whatsoever. ;-(

I believe this is the ECU type I have on the Meriva:

I think the choices I have are:

Find a second hand one and see if I have the right tools (OpCom) to be able to program it into our car (the outcome of that may be a function of how the ECU comes to me and if I have the code etc). (£30-50)

Find the set of keyed parts and change the lot (~£50-200)

Find a 'reset, tested and ready to program' ECU from a private seller / breaker and hope my OpCom can program it. (~£100)

Find a 'reset, tested and ready to program' ECU from a private seller / breaker but with a bit of a guarantee and hope my OpCom can re program it. (~£100-150)

Buy or get my ECU remanufactured and get a one or even two year guarantee (that shouldn't need re-programming if it was mine. (~£250)).

Or buy a new one off Vauxhall (£607) and hope my OpCom can re program it or get them to fit it for me.

Now, the 50k 2004 Meriva was given to me and I'd rather like to get it going again (partly for Mum as it was 'theirs' before Dad died and partly) because I've fitted a decent / removable swan neck towbar and with the seats all folded flat it's handy as a little van. It's also nice and easy for the Mrs to get in and out off with her arthritis and two new knees.

I think I'm going for a re-manufactured one with two year warranty as at least that way my investment is protected for a couple of years. ;-)

Cheers, T i m

In article , T i m writes

Oh, yuck. Yeah, forget trying to fix that yourself.

Quite, and if you had something that appears to be so fine / delicate, would you bolt it onto the end of the engine? ;-(

Cheers, T i m

Fine in the days of solder through components - but not so easy with surface mount which is machine assembled and soldered. And that's before some of the even newer techniques.

In article , T i m writes

'tis why they potted it, to protect from vibrations but also making repair impossible. I wonder how the repair services manage it.

But not heat?

In this case I think it's the least of my problems from a DIY repair POV. ;-)

I think it is 'potted' in a fairly soft silicone and I'm not sure if they can dissolve / liquefy it off somehow (there must be a solvent mustn't there) or peel it off (less likely, considering how thin the wires are).

Mind you, *if* they were re-making all the socket to PCB connections anyway ...

Anyway, I've got the ECU and BCM out (the latter wasn't hidden at all ), now it's just the instruments, the key pickup thing and a key.

As the ECU does actually work (the car runs fine once started, ignoring the permanent ignition light and intermittent speedo, rev-counter and engine temp gauges that is ), hopefully it will

Cheers, T i m

In article , Mike Tomlinson scribeth thus

Give these people a call we used them a few years ago to sort out the ABS brake controller on a Volvo it only took them Two days from here to there and back around 100 quid and it worked fine:)

Volvo wanted ISTR in excess of £££ 700 sheets;(...

Yeah, £607, just for the ECU from Vauxhall. If you buy a tyre for 40 quid you often get it fitted, balanced and new valve for free!

Thanks for that Tony. However, I've just this second paid for a reman repair online and will drop it (and the other bits they need) in on my past (Colchester) this week.

I also aim to collect it (all), that way it can't (shouldn't) get damaged in transit and it's nice to know I can go there in person, for all sorts of reasons. ;-)

Funnily enough, I did spot the Co you linked to previously but I wasn't sure exactly what the cause of the fault was at the time. I think the price is about the same, but they offer a lifetime warranty (rather than two years).

Cheers, T i m

Peel it off, not bolting it the engine, is a way more sensible solution though.

Get a car that can be serviced - in a paddy field.

I was thinking about that and what I could do about it.

The issue may be the loom was designed with the thought that the ECU moves with it so that if one moves the ECU off the block, even if fairly close to where it is now, but mounted from the body, then the wiring to the ECU might be under more stress?

Of course, still being up high in a fairly crampt and vertical engine bay, can't help with the heat levels either. [1]

I noticed a 2004 1.6 16V Meriva on eBay that had done over 200,000 miles and who knows if it had done so on it's original ECU? Daughters

Maybe there was a bad batch, such things do happen don't they? [2]

Cheers, T i m

I doubt the temperature gradient under the bonnet is much different to that in domestic central heating boilers, and the PCB's in there mostly survive.

Most ECU's are mounted in the cabin, but are also known to fail, even the ones that are not mounted under the carpet where they are bound to get wet! (Here's looking at you BMW.)

If you get your ECU repaired and it only lasts five years, the cost per mile is likely to only be a small part of your motoring budget.

Chris

Nice, that's the sort of 'bench repair' I have been doing most my life (allbeit not using that technique). ;-)

Not set-up for re-balling and such but have a lad who is. ;-)

Cheers, T i m

British bike industry was full of stories like that. Norton crankshaft came in left and right halves that bolted on the flywheel in the middle. They used to grind cranks as a matched pair, then left ends went in one box, right ends in another, never to meet ever again. Then had to use special wobbly "superblend" main bearings to accommodate the resulting angular misalignment.

I've got a head full (5/8) of guttered inlet valves on a petrol engine. Expected on Diesel but not on petrol and certainly not a common issue for inlets. There was a bad batch. Within 6 months of the date they arrived in use, Nissan had a TSB for replacement BUT only if the owner complained of poor starting. Once running they were fine, very few complained and when you lift the head at 150K and find them, they won't look at it.

Ford made V4 and V6 OHV engines with tufnol gear driving the cam. Lasted the warranty, then the sump had to come off to get all the shredded gear teeth out and clean the pump strainer. The Triumph motorcycle engine also used a tufnol gear as an idler between the crank and the 2 cams - exhaust in front and inlet behind the cylinders. They had a prime number of teeth so spread the load across all teeth. And motorcycles were rebuilt every 5000 miles anyway.

Honda made twin cylinder motorcycles with 180 crank, bang, bang, bok, bok. Cam had no middle bearing, the chain was at the middle and flexed the cam, they snapped. Next version they put a middle bearing in, they snapped the tensioner (I found 5 "tails" in the sump). Then they went to a 360 degree twin even firing bang, bok, bang, bok, HiVo inverted chain, bullet proof tensioner but all way over the top as the switch to 360 was the real fix.

Honda hadn't learnt nothing, had the same problem with VF750F, only cure for that was the VFR gear driven cams.

No!

Lovely (not).

I've got one on the floor of the kitcar. ;-) Was the Essex engine one of such? I had a Ford V6 in my Bedford CF Campervan. ;-)

But at least you could generally get the sump off without the engine falling to bits. ;-)

That may have also been the setup on my Madras Enfield 350 Bullet but I think they were iron gears?

Didn't the CX500 (Plastig pig / maggot) suffer something like that?

Sure. Much more 'balanced'.

It's a same isn't it when they seem to go back to something that was known to be bad. Makes you wonder why they do it. Mind you, I'm not sure they run vehicles long enough in Japan for it to be an issue for them do they?

Cheers, T i m

I've stripped and rebuilt dozens of Triumph engines; I used to race a home-built Triton in the late Sixties. None of them had a Tufnol idler, they were all steel. In fact, part of the tuning mods I did was to machine them back to half their original thickness.

Perhaps you were thinking of the magneto drive gear, which indeed was Tufnol?

Chris

For exactly the same reason. The cam has a portion where no valves are in motion and so has no load. 1st cam comes round and whack it's full load.

The VF750F after the CX500 shows they still don't understand the reasons. They got away with the fully unloaded cam drive on Gold Wing and Pan-euro as they are belt drive.

The fix is to use the same design for cam chain and tensioner that they use on singles - which are fine as they know those have no load and then full load.