Oh Dear.... KV5.... but now KV6 again - Page 2

Phil · 19th April 2009, 20:26

Quote:

Originally Posted by lowedb

I've also had a car (not a 75) where there were no fault codes, but wouldn't start. No sparks at all.
The supply to the coils was down (someone had unplugged it, don't ask) but the ECU doesn't see the supply, only the load on the trigger circuit. So fault codes aren't 100% reliable.

A short like that damaging the ECU though is pretty poor design. I take it it wasn't a Rover Phil?

It was a Honda.

The way the injector had gone it gave the same effect as doing a direct short.

Bernard LPG · 19th April 2009, 20:28

Quote:

Originally Posted by Phil

Not nescessarily, I've had one before with no fault other than the misfire code, the injector had shorted inside giving perfect continuity when tested. This had blown the ecu as the injector provided a direct short.

But it should not be perfect continuity on test, there should be a few ohms across each injector. You can get at the wires to them at the ECU connector in the plenum. Test across each wire to 12v ignition. From memory (not good any longer!) about 13 ohms.

Departed · 19th April 2009, 20:29

Quote:

Originally Posted by Phil

It was a Honda.

The way the injector had gone it gave the same effect as doing a direct short.

Yes but they should be short circuit proof anyway. Worst, it should take out a fuse.

Phil · 19th April 2009, 20:30

Quote:

Originally Posted by Bernard LPG

But it should not be perfect continuity on test, there should be a few ohms across each injector. You can get at the wires to them at the ECU connector in the plenum. Test across each wire to 12v ignition. From memory (not good any longer!) about 13 ohms.

Thats right, but the injector I refer to was faulty, direct short hence no resistance. A good injector, as you say should show around 13 ohms. Good point about the ecu wiring, never thought of that.

Phil · 19th April 2009, 20:33

Quote:

Originally Posted by lowedb

Yes but they should be short circuit proof anyway. Worst, it should take out a fuse.

Should do I agree. But didn't in this case.

Its not the only instance of this happening I've come across. Not on a Rover though.

Bernard LPG · 19th April 2009, 20:39

Whatever happens, while testing, do not turn on ignition with any device disconnected. The coil drivers, for example, will almost certainly burn out if livened up and not connected to the coils - don't ask! The injectors may well be the same.

Jules · 19th April 2009, 21:56

Oh bad new Dave
Hope it's not a compression issue. (spark plug would be good news)

You can get very quick rough idea of compression by "feel"
ie push the car vary slowly in 2nd gear with ignition off.

Or turn the flywheel bolt

Worth a try & quicker than removing inlet manifold.

Many many Thanks for the pressie today BTW.
I can feel a Stocktake Coil/injector quick tester coming on

Departed · 20th April 2009, 12:40

Was thinking about this on the way to work.

Probably an obvious point, almost feel daft for suggesting it...

Are you sure your'e on the right cylinder? Reason I ask is on my V6 you couldn't swap coils for 5 and 6. One is on front bank (coil with lead) and the other is on rear bank (coil on the plug).

I'm pretty sure 6 is in the rear bank, but the front bank leads are marked.

It's the sort of thing I've done before now!

stocktake · 20th April 2009, 18:53

Good spot Duncan, I actually swapped coils 4 and 6, just in my haste to type 5 & 6 came out.
As I read it front bank from alternator end 1,3,5
Back bank from same side 2, 4, 6.

What a banging and clanging when started up this morning, I fear the end is nigh for the lump.

Parked up in the drive now, going no where

Will not have any serious time to look either for the next fortnight

Simon · 20th April 2009, 19:00

Things don't sound at all good do they Dave

Such a shame especially considering the fun and enjoyment for the preceding daytime and evening.

Let's hope things aren't terminal and it's just a coil pack or something [gets out prayer mat....]

19th April 2009, 21:56	#17
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Oh bad new Dave Hope it's not a compression issue. (spark plug would be good news) You can get very quick rough idea of compression by "feel" ie push the car vary slowly in 2nd gear with ignition off. Or turn the flywheel bolt Worth a try & quicker than removing inlet manifold. Many many Thanks for the pressie today BTW. I can feel a Stocktake Coil/injector quick tester coming on __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

20th April 2009, 18:53	#19
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,593 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	Good spot Duncan, I actually swapped coils 4 and 6, just in my haste to type 5 & 6 came out. As I read it front bank from alternator end 1,3,5 Back bank from same side 2, 4, 6. What a banging and clanging when started up this morning, I fear the end is nigh for the lump. Parked up in the drive now, going no where Will not have any serious time to look either for the next fortnight __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident

19th April 2009, 20:39	#16
Bernard LPG I really should get out more....... 75 V6 Saloon 2003 LPG MGZT V8 260 LPG Join Date: Dec 2006 Location: Evesham Posts: 2,134 Thanks: 0 Thanked 1 Time in 1 Post	Whatever happens, while testing, do not turn on ignition with any device disconnected. The coil drivers, for example, will almost certainly burn out if livened up and not connected to the coils - don't ask! The injectors may well be the same.

20th April 2009, 12:40	#18
Departed Retired -- Join Date: Jan 2007 Location: -- Posts: 3,785 Thanks: 0 Thanked 4 Times in 4 Posts	Was thinking about this on the way to work. Probably an obvious point, almost feel daft for suggesting it... Are you sure your'e on the right cylinder? Reason I ask is on my V6 you couldn't swap coils for 5 and 6. One is on front bank (coil with lead) and the other is on rear bank (coil on the plug). I'm pretty sure 6 is in the rear bank, but the front bank leads are marked. It's the sort of thing I've done before now!

20th April 2009, 19:00	#20
Simon Banned - Join Date: Nov 2006 Location: - Posts: 10,318 Thanks: 0 Thanked 4 Times in 3 Posts	Things don't sound at all good do they Dave Such a shame especially considering the fun and enjoyment for the preceding daytime and evening. Let's hope things aren't terminal and it's just a coil pack or something [gets out prayer mat....]