www.gt4dc.co.uk
http://www.gt4dc.co.uk/forum/

Starting - spinning the engine to build oil pressure
http://www.gt4dc.co.uk/forum/viewtopic.php?f=1&t=7693		 Page 2 of 2
Author:  darrylp [ Wed Jan 04, 2017 6:17 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
If you break the efi fuse circuit, the ECU surely will be reset and thus need a learning cycle or two. Not sensible IMO.

--
Darryl
Author:  Sirius [ Wed Jan 04, 2017 10:40 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
darrylp wrote:
If you break the efi fuse circuit, the ECU surely will be reset and thus need a learning cycle or two. Not sensible IMO.

--
Darryl


A valid point but I'm running an aftermarket ECU which doesn't have 'learning' capability so I think that aspect should be OK.
Author:  two_OH_five [ Thu Jan 05, 2017 12:54 am ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
Pull the IGN fuse (internal fuse box in the knee roll I think) and see if the oil pressure light still works and make sure it will crank but not fire

If that works then the solution is simple, a switch in one of the wires off the main ignition switch.

Frelling wiring is sooooooo convoluted, bring back the days of a coil and points combined with a carb when I could work out how to hotwire a car without staring at diagrams for an hour
Author:  Sirius [ Thu Jan 05, 2017 3:20 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
two_OH_five wrote:
Pull the IGN fuse (internal fuse box in the knee roll I think) and see if the oil pressure light still works and make sure it will crank but not fire

If that works then the solution is simple, a switch in one of the wires off the main ignition switch.

Frelling wiring is sooooooo convoluted, bring back the days of a coil and points combined with a carb when I could work out how to hotwire a car without staring at diagrams for an hour


Sounds straightforward enough - by pulling the IGN fuse any thoughts on whether the injectors will still be firing?
Author:  two_OH_five [ Thu Jan 05, 2017 4:00 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
It's difficult to say for sure with an aftermarket ECU
It should kill the switched ECU power but unlike pulling the EFI fuse it should leave the permanent battery supply enabled. If your ECU requires the switched power to function then the injectors won't fire
However it should also disable the fuel pump so even if the ECU is alive there shouldn't be any fuel outside any residual rail pressure
Author:  Kris [ Thu Jan 05, 2017 5:56 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
Think the best option is to open the bonnet and remove the EFI fuse?

I say this as removing is a simple job and should only be necessary if the car has been stood for some time, say 3? weeks+. The hassle involved with providing another solution, (even with entering an aftermarket ECU setup), probably isn't worth the time and trouble, just pull the fuse?

I don't have evidence of a particular length of time that passes that necessitates the priming of the oil system, but as you are aware, my engine required oil pump priming before I could start it as it had been left for a long time... the 3 weeks is a bit of a guess :P
Author:  Nibbles [ Thu Jan 05, 2017 7:30 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
Bear in mind that frequently pulling & replacing a fuse will end up with weakened contacts leading to poor connection etc. Better to do it with a switch, even if it's located under the bonnet.
Author:  two_OH_five [ Fri Jan 06, 2017 8:21 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
If it's dead simple with an aftermarket ECU via map switch/anti theft ect why not do it?

With the stock ECU it makes more sense to find a way of doing it without necessarily loosing all of the previous learning data. Finding this can be simply done by pulling a different fuse (assuming you weren't the poor sod pouring over wiring diagrams :lol: ) also seems worthwhile.
And how many people would have ever thought about using a pressure switch to make the whole process automatic?
Author:  бешаный 202 [ Mon Jan 09, 2017 9:53 am ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
I think that nothing bad will happen if you just start the engine. All the different things I think just superfluous.
Author:  Sirius [ Mon Jan 09, 2017 7:22 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
бешаный 202 wrote:
I think that nothing bad will happen if you just start the engine. All the different things I think just superfluous.


You are probably right. Interesting to look into it however.
Author:  Diceman [ Mon Jan 09, 2017 10:39 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
I do wonder if it's worse to crank for longer with low load and oil pressure or start the car and idle for a shorter time period with low oil pressure. I honestly don't know. If you could operate an external oil pump to build pressure prior to engine rotation then it's clear.

Anyone any thoughts?
Author:  Nibbles [ Tue Jan 10, 2017 7:53 pm ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
I've often wondered. Oil pump inefficiency / leakage is worse at lower RPM so in theory the engine will do a lot more revolutions before oil arrives at cranking speed than at fast idle (cold start) RPM. On the other hand, there is less load to break the oil film remaining.
Author:  бешаный 202 [ Wed Jan 11, 2017 7:52 am ]
Post subject:  Re: Starting - spinning the engine to build oil pressure
I just set myself the oil pump 4 gen.
There rotor by more than 3 gen.
I had to change something, but I was doing it all along the way.

Altezza possible and from the oil pump to deliver, if desired, but I believe that it is too ...
Page 2 of 2 All times are UTC + 1 hour
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/