a question about the oil pressure swich

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parkin10
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Post Tue Nov 02, 2010 9:40 pm

the dealer leads are pricey
i put on some good quality made in germany leads because the old leads were odd ones
without the plastic channel to hold them away from the exhaust manifold
and no real effect what evers wrong i have not touched on it yet
it may be your wiring idea yet
did i say that theres allways a smell of fuel from the exhaust before it finaly starts up
i cannot remember seeing a grove for the o ring to go into i will have a look next time i am there with the cap off
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Fred555
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Post Tue Nov 02, 2010 10:03 pm

It's the plastic channel on the dealer leads that people swear at for retaining moisture, others have no problem and some pack it with silicone dielectric grease and then have no problem - I don't know what to think about that channel.

Well if there is a smell of fuel from the exhaust before it finally fires then injection system is firing so that probably means ignition not sparking initially.

Take a look at a dealer parts diagram using the chassis number to check on the "O" ring business before you take anything too fiddly apart - you may be putting it back the way you found it but somebody else may have put it back together wrong before you touched it.
All you need to fix anything is grim determination – that and belief.
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parkin10
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Post Wed Nov 03, 2010 1:42 am

ignition not sparking initialy?
pop a old plug in a lead and cold crank theres a spark allright straight away
see why i am struggling
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Fred555
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Post Wed Nov 03, 2010 10:12 am

The spark you see on an old plug on an old lead lying on top of the cam cover is not the same as a spark generated with the ignition system operating under load - i.e. engine compression.

The compression increases the effective resistance the spark has to overcome, to jump, to be able to successfully spark, more resistance needs more HT KV voltage and that requires more current supplied to the coil, an oscilloscope watching the coils behaviour under load on a rolling road is the only way to definitively prove anything and you can still have heat sensitivity issues beyond that even then, so realistically swapping coils is the only practical shortcut (in general terms).

It is what I was saying earlier - an ohmmeter only detects open circuits or dead short circuits - because it does not subject anything to the operating load of the device but things can fail to operate correctly only under load and that is where voltage and current tests become critical.
All you need to fix anything is grim determination – that and belief.
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parkin10
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Post Wed Nov 03, 2010 9:33 pm

thanks fred for all your input
i am sure you can see the cars problems are very deep and not self evident
i think i will solder up the earths in the engine loom when i find the time to have the car off the road and time to do the job and then see
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Fred555
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Post Thu Nov 04, 2010 11:30 pm

That's the problem with cars that have high "Build Quality" they are so tough that very little fails outright (easy to find) instead components have a habit of still working while also fading away! Teasing everyone with the - I bet you can't find me kind of fault.

If you do the loom discard the crimped splices and solder the bare wires together - adding solder to an already oxidised crimp makes it worse - Good luck I hope you nail it in the end.
All you need to fix anything is grim determination – that and belief.
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parkin10
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Post Sun Jan 23, 2011 10:07 pm

just for fred555
i did nail it :D
it was simply a vacuum leak
it was drawing air though the brake servo :mad:
changed it and the engine runs nice now
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Fred555
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Post Sun Jan 23, 2011 10:38 pm

Good one Brilliant! Great to hear - What tipped you off to look at the servo?

Where did you get the servo? (How much in other words!)

Go on change all the small vacuum hoses you will be amazed what else will suddenly come back into full operation! - buy 3-4Meters of hose at the dealer or get some silicone (supposedly indestructible) vacuum hose at a speed shop.

I really should go back to big block (over 5.5Litre) USA V8s - so much air displacement the only kind of vacuum leak that would have any effect on running would be audible as a dull roar at the leak & therefore easy to find.

Me? - Got MOT but need new front brake hoses so will buy "Lifetime Guaranteed" "All Stainless Steel" braided racing ones from HEL only £13 each! In translucent red! Am tempted to rebuild front calipers with seal and boot kit from dealer (piston still ok & no leak but dust boots not good) anyone done this - should you use "ATE Brake Cylinder Paste" (or will DOT4 Suffice) and if grease where do you get it? Any ideas/opinions anyone?
All you need to fix anything is grim determination – that and belief.
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parkin10
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Post Mon Jan 24, 2011 12:50 pm

the only caliper problem ive had was on my bike
rear caliper was seized up i warmed up the caliper with a hot air gun got the piston out cleaned the fur off the caliper body copper sliped it (cos i had it) poped it back together never been a problem since

the servo?
just one day stopping for the car in front at some lights the servo decided no help from me
:eek:
supprisingly the brakes were working fine up to that
i think the servo was leaking air all the time ive had the car
bone yard for the servo and master + rear bumper trim £25
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Fred555
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Post Mon Jan 24, 2011 3:16 pm

Kudos on the price!

I wonder if the big "O" ring that seals the master cylinder to the servo failed (which would cause a huge vacuum leak and zero servo assistance) or was the servo diaphragm itself ruptured or was it a rusty servo housing causing the vacuum leak?
All you need to fix anything is grim determination – that and belief.
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parkin10
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Post Tue Jan 25, 2011 9:02 pm

was not the o ring
i think i would have found that sooner
the old servo made a kind of servoish noise that the replacement does not
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parkin10
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Post Fri Feb 05, 2021 7:23 pm

I've just rediscovered this old thread of mine!
I still have this e30
The engine start up issues were solved when I changed the fuel injectors
I have used the car day to day for 12 years straight
She has over 200,000 miles on it now still starts and pulls well
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martauto
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Post Sat Feb 06, 2021 1:59 pm

parkin10 wrote:
Fri Feb 05, 2021 7:23 pm
I've just rediscovered this old thread of mine!
I still have this e30
The engine start up issues were solved when I changed the fuel injectors
I have used the car day to day for 12 years straight
She has over 200,000 miles on it now still starts and pulls well
WOW !! I will start a thread .....................the 200K club

Here`s a link

viewtopic.php?f=1&t=281599

Mart.
Only the E46 cab left now.
Just got too old.
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Blanca
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Post Sat Feb 06, 2021 2:25 pm

I had that problem, cranks OK etc but coughed a bit didn't start, turned out to be the underbody fuel pump, belt it with the wheel spanner and OK again.
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