Ford Scorpio Forum (https://www.fordscorpio.co.uk/cgi-bin/yabb/YaBB.pl)
General >> Give/Need advice to/from others >> Idle problem
(Message started by: Simmo on Nov 17th, 2012, 3:57pm)

Title: Idle problem
Post by Simmo on Nov 17th, 2012, 3:57pm
Early today I started the car only to find that it did not want to idle. It ran but stalled once you released the throttle. Managed to do a trip but not pleasant!. My 'best guess' was the Idle Air Control Valve. On checking I found that the wiring to this item was defective and in fact one wire fell off. Checking round I found defective insulation on two other sections. Firstly to the throttle position sensor and secondly to the air inlet temperature sensor. These last two I managed to tape up,in the short term, and with luck managed to reconnect the broken cable to the IACV. This was sheer luck as it had fractured inside the plug BUT there was just enough wire to touch with an instrument soldering iron and thus rejoin the cable. On putting things back together the engine ticked over as normal. Clearly the problem was the wiring to to the IACV.


http://www.drich2422.ukfsn.org/MIKE%20SCORPIO%20PICTURES/Scorp%20Wiring%20001.jpg


http://www.drich2422.ukfsn.org/MIKE%20SCORPIO%20PICTURES/Scorp%20Wiring%20003.jpg

You will see that all these wires emanate from the connector on top of the injectors. Lifting the lid on this it is clear that the wires going in to it are all in good condition and thus I should be  able to remake from this point. However the three items I listed have in total 7 wires going to them. Opening the 'lid' shows that there are at least another four within the outer sheathing. If you look you can see a section of that outer protective sheathing going down by the throttle position sensor. Can any one tell me what is below there?. I suspect it may be the temperature sensors but ,for the life of me, I cannot see for sure. I intend to get the correct coloured wires and re-make the loom so it would be great to know what they connect to.  ;)

Title: Re: Idle problem
Post by Tompion on Nov 17th, 2012, 10:47pm
Mike,

They’re all part of the Fuel Cut-off Loom here:
http://www.fordscorpio.co.uk/dohcloom.htm

There’s a single wire goes down to the oil pressure switch roughly in the middle below the manifold. There are 2 wires going down to the crank position sensor just behind the oil filter. On my 2.3 they go down at the front of the engine and run along below the manifold I would imagine it’s the same on yours.

I suspect you know where the 2 coolant temp sensors are but just in case they’re in the side of the stat housing you can see one below the right intake by the hose to the matrix the other single wire one I think you can just see through to between the matrix and rad hoses.

Many of the plugs on my old harness were crumbling but I’ll try & find it and let you have it at the Kent meet in case the IAC one is worth having.



Title: Re: Idle problem
Post by Simmo on Nov 18th, 2012, 6:41am
Thank you Dave. LIke you I have found these plugs are now becoming brittle. I have a couple of spares and I am in the process of trying to refurbish them......that's posh speak for working out a 'Tompion bodge'...... ;D
I think there might be a way by using some new 'internals' from Vehicle Wiring Products and will explore this on Monday. I hope your car goes through the MOT ok on Monday. Look forward to seeing you next Sunday and I'll hold off ordering from VWP until then as I might try and remake a whole loom. Keep me out of mischief over the winter days!.  Good luck, Mike.

Title: Re: Idle problem
Post by Simmo on Nov 18th, 2012, 7:11am
This video (http://www.youtube.com/watch?v=7iGGDPD4A4k) gives a general impression of how to refurbish a ford connector as does This one (http://www.youtube.com/watch?v=7orqGTmbOmY). The actual fittings in this are similar to ours but the principal is the same, ie: release the internal pins and repair the wiring. Shame the quality of the second one was not better. :)
If you want to tackle a loomThis (http://www.benzworld.org/forums/w140-s-class/1363884-make-your-own-wiring-loom-heres.html) might be a good place to look. ;)

Title: Re: Idle problem
Post by Simmo on Nov 18th, 2012, 3:38pm
http://farm9.staticflickr.com/8337/8195287111_e5e071bd7c_z.jpg (http://www.flickr.com/photos/90140801@N05/8195287111/)
 
This picture shows one of the plugs dismantled. A fiddle but the trick is to remove the blue section, as seen in the videos, and then insert a tiny instrument into the unit in order to release the 'tags' which secure the female fittings in place in place. If you look at the top fitting you can just see a tag. There is one on the top and the bottom so they both need to be  released. The metal fittings are crimped to the wires. I think the lugs and the rubber inserts are available...subject to a check tomorrow. They are listed in various sizes.  :)

Title: Re: Idle problem
Post by Tompion on Nov 19th, 2012, 2:07pm
Mike,

Found the old harness – it’s a mess. There are a few plugs the same as used on the IAC if you don’t mind the wrong colour wires, one of them has reasonable tails you might be able to use.



Another MOT out of the way for my car:)

Title: Re: Idle problem
Post by Simmo on Nov 20th, 2012, 7:50am
http://farm9.staticflickr.com/8067/8202596676_8fe0d24f16_z.jpg (http://www.flickr.com/photos/90140801@N05/8202596676/)
http://farm9.staticflickr.com/8198/8202594086_759888d0be_z.jpg (http://www.flickr.com/photos/90140801@N05/8202596676/)
In order to remove the tags from the holders I made up this instrument. My 'engineering' skills know no bounds!! ;D and only on here would I reveal the details of manufacture!. ::) Searching for something slim and strong enough I came across a metal insert from an old wiper blade rubber. Perfect!. Retrieved a small piece of 9mm square beading from the garage roof 'store'. Made two small cuts in the end with a Stanley knife, using the tag as a guide for width,cut off two @ 50mm lengths of the metal and gently tapped them in to place leaving 30mm. Applied wood glue to the cuts. Left in vice overnight. The pictures above show how the tool works. Essentially all it does is flatten the tiny clips which hold the tags in place and allow them to be pulled backwards. :)

Any suggestion that I am trying to beat Tompion to 'Bodge of the Year' will be vigorously defended! :D ;D

Title: Re: Idle problem
Post by gozz on Nov 20th, 2012, 9:19am
Simmo.
If I were you I would contact the patents office ASAP,Timberiuswiperiumproggler mk1 ?  ;D
                                                                              GOZZ.

Title: Re: Idle problem
Post by Tompion on Nov 20th, 2012, 1:16pm
Excellent Mike you’re learning – never throw anything away. ;D
I’ve got plenty of old tat just looking for a use I’ll bring a boot-full along for you, I’m sure Lynn would appreciate it. :D

Title: Re: Idle problem
Post by Mike H on Nov 22nd, 2012, 9:23pm
Re original post, bit unusual, these wires aren't near anything hot are they?

Or is it just corrosion?

Title: Re: Idle problem
Post by Simmo on Nov 23rd, 2012, 8:23am
No they are not so it appears to just be the results of age.  The connectors to the IACV and the air inlet sensor do of course get moved a fair bit in the course of removing the inlet trunking for access for a variety of tasks so I suppose they are subject to more physical movement than others. The TPS does sit close to both the thermostat and the block so it does get a fair share of heat.  :)

Title: Re: Idle problem
Post by Dave2302 on Nov 24th, 2012, 10:15am
Nice tool  ;D

I bought a lovely set of 12 different ones in a case from the Snap On dealer years ago, very handy  :)

However, bet I got ripped for a hell of a lot more than yours cost LOL

Nice one  ;)

That wiring degradation is typical of all Fords of that era, the Cosworth owners just noticed it first due to the ridiculous underbonnet temperatures, but it is just cr@ppy wire insulation on all Ford cars of the period  ;)

My Cosworth in the Puma is now runing at a nice stable 82 C and is much happier for it, with the stock set up they average around 98 -102 C.............Waaaay too hot for my liking  :)

Next time your in a Scrappy, have a look at the wiring in front of the radiator on a Mondeo of similair vintage  ;D ;D ;D

Dave



Ford Scorpio Forum » Powered by YaBB 1 Gold - SP 1.3.1!
YaBB © 2000-2003. All Rights Reserved.