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General >> Problems >> Misfiring Ultima Cosworth
(Message started by: georgeodyphotos on Dec 28th, 2007, 12:24am)

Title: Misfiring Ultima Cosworth
Post by georgeodyphotos on Dec 28th, 2007, 12:24am
I have a 24 valve Cosworth Estate which has intermittent misfiring problems, sometimes rendering me stranded at the side of the road. My local Ford garage hooked it up to their diagnostic machine and it showed '2x fault codes. PO171 System too lean bank one.  PO174 System too lean bank two'  What does this mean? They don't seem to know.  Can anyone please advise?  Drove from Falmouth to Minehead today and the first 50 miles were horrendous and then from Exeter to Taunton she ran almost perfectly with just the occasional missing. Help!

Title: Re: Misfiring Ultima Cosworth
Post by Snoopy on Dec 28th, 2007, 7:41am
Does THIS (http://www.fordscorpio.co.uk/codes.htm) help along with the associated pages



Title: Re: Misfiring Ultima Cosworth
Post by pappa on Dec 28th, 2007, 9:28am
Oh boy  :'(

I've been on that road too. Had all the the almost same symptoms, excluding the stranding
of the road (touching wood here). My problems went away when I swapped the engine
to a 2.3 DOHC. But, that brings along a heap of work and other problems :)

Ok, what I would do if I was you:

Plug the EGR valve hose, the one that controls the EGR valve. A very good description
of the EGR system is here: http://www.fordscorpio.co.uk/egrmonitor.htm
The hose you need to plug is the one going into the top of the EGR valve.
This will very often cure many idling/low rpm related problems like jerking
at cruise speed etc.  Note that this is only a temp solution and may even not
help you, but having had a ton of idling, rough ride and other issues with my
past BOB Engine, I found this to be the best solution for me. And finally
when I swapped the engine, I found out that the EGR pipe behind the engine
was very loose, allowing an airleak into the the system = system lean problem.
An airleak sounds like your problem as well. They tend to get better when the
engine gets hotter. And there are many, many places where the airleak can
occur. So it is a good idea to go through all the vacuum hoses you can to see
if any of them are broken or loose.

Then there's the variety of electrical problems... But system too lean sounds
like it's sucking too much air into the system and the ECU is trying to compensate,
but fails. Giving you a headache and the DTC's to the car.

Mmm... search the forum with "misfire" and related search strings, you'll find a lot
of information which may help you.


Good luck, happy hunting and welcome to the forum!

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Dec 28th, 2007, 9:38am
Thank you Snoopy for the info, but having got the error codes, what does one do next? In the 'good old days, when I did all my own servicing, if an engine was running too lean or too rich, it was a simple job to adjust the mixture. In this case, what would cause the lean mixture and how is it corrected?  I don't want my garage to replace umpteen parts on a trial & error basis, costing me a fortune.  what do you think?

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Dec 28th, 2007, 9:42am
P.S I should point out that I don't have facilities to do my own servicing so I need to point the garage in the right direction if possible.

Title: Re: Misfiring Ultima Cosworth
Post by scorpio_man on Dec 28th, 2007, 12:43pm
hi there

to me, your issue sounds more like this (http://www.fordscorpio.co.uk/fuelreg.htm).

for a garage down your way, use powercraft (http://www.powercraftengineering.com/).

bill (the owner) is a member and knows all about the scorpio.

hth


Title: Re: Misfiring Ultima Cosworth
Post by Pegasus on Dec 28th, 2007, 11:05pm
... and have a look at this (http://www.fordscorpio.co.uk/fuelmonitor.htm)

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Dec 29th, 2007, 10:31am
Thanks everyone for your tips which I've emailed to my Ford garage. If they can't sort it I'll certainly try Powercraft who scorpio_man recommended, It's a bit of a trek from Minehead to Paignton but may well be worth it. Thanks again.

Title: Re: Misfiring Ultima Cosworth
Post by jonnycab on Dec 30th, 2007, 3:21am
Personally, I'd be looking in the direction of a faulty fuel pressure regulator  :)

Title: Re: Misfiring Ultima Cosworth
Post by TiberiuS on Jan 1st, 2008, 6:46pm
Certainly sounds like a fuel issue, if it were a more common ignition issue, you'd be running rich :-/

Could be a sticking injector, but I doubt that one dead injector would be enough to kill the engine, one injector wouldn't affect both banks either. My money's on either fuel regulator or EGR fault as the other guys said.

Could also be a fuel pump problem, worth replacing the pump relay as a precaution.

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 14th, 2008, 5:33pm
And so the saga continues... My Ford garage fitted a new fuel pressure regulator and told me that the collars either side of the VIS valve are faulty. One has been bodged up and the other is perished, apparently. "We'll order them for you and that should cure the problem" they said. They called me this afternoon and guess what?  "There are NONE IN THE COUNTRY AND THEY WILL HAVE TO COME FROM EUROPE" they say  "and that will take a week".  Is this possible and does anyone know of any of these collars floating around?
I seem to have been very unlucky with this car. It is in near showroom condition in and out but I think the previous owners skimped on some mechanical things.  I have only had it since last May, and have so far had to have fitted: new water pump, new front coil springs, (while these were being fitted I was advised that front discs were heavily corroded and that it would save on labour if they were done at the same time), new air idle control valve, full service at £300, new tyres and tracking, and the current running fault. Haven't had all the invoices yet.... :(  The only consolation (I keep telling myself) is that I didn't pay a fortune for the car, which, when running properly, is a dream to drive.  But I couldn't sustain these kinds of running costs for very long.

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 25th, 2008, 6:42pm
Well, the bill is now up around the £800 mark and still not fixed..... The garage says the mechanic, having fitted various things, including fuel pump relay, is 99% certain that the problem lies in the CRANKSHAFT POSITION SENSOR. Has anyone heard of this?

Title: Re: Misfiring Ultima Cosworth
Post by Matt on Jan 25th, 2008, 7:08pm
when they fail the car wont start at all, and the dont really sort of work, they either do or they dont, same as the cam position sensor,

have they tried changing the fuel filter (located at rear the under the car near spare wheel)?

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 25th, 2008, 8:07pm
I think they changed the fuel pump relay and 'tested' the pump.

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 25th, 2008, 8:09pm
I wish I'd tried to get the car to Powercraft in Paignton. Maybe it would have been fixed by now.....

Title: Re: Misfiring Ultima Cosworth
Post by TiberiuS on Jan 25th, 2008, 11:02pm
I've heard of guys on other forums having issues with the crank sensor part-failing and becoming 'noisy' but not sure whether it's really possible or just people trying to explain gremlins which come and go :-/. As Matt says it's normally a go/no go thing, you go to the car one morning and it just won't start where the sensor has gone open circuit and the ECU isn't getting any signal. The sensor is just a coil which reads a toothed cog attached to the engine and puts a signal out so the ECU knows whereabouts the engine is in cycle.

Did they put a gauge on the fuel rail and test the pressure? That's the only sure-fire way to check there's enough fuel getting through to the injectors, if there's good fuel pressure you can rule out everything in the fuel system up to the injectors.

Lack of fuel or unmetered air getting in somewhere, they're the only two things I can think would cause it :-/

Can they scan it and get the actual fuel trims? That might help the guys on here if they have more info.

Regards, Bruce.

Title: Re: Misfiring Ultima Cosworth
Post by scorpio_man on Jan 26th, 2008, 10:03am
hi there

i had the ckp go on an old sierra. it started failing first of all. mainly approaching roundabouts, for some reason. :-/ it would try to cut out, etc.

so, they could be right, but it's not a usual problem on here, though. re the cam sensor, i've only heard of that failing once (jc?).

hth

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 31st, 2008, 10:21am
Hi guys, At last the problem is sorted! For your information I will copy what is written on my invoice from Ford garage. "Hooked up IDS and carried out DTC check. No fault codes listed. Test drove and vehicle cut out numerous times. Re hooked up IDS and fault codes PO171 and PO174 bank 1 & 2 lean mixture. Using DAT logger unable to test fuel pressure regulator/ fuel pressure.  Spoke to Ford technical and was advised to clean up all electrical connections and tighten all air hoses/pipes. Ford technical advised fuel pressure regulator be replaced (part No: 73346840) Supplied and replaced fuel regulator valve, found air intake pipes split when dismantling. Ordered pipes and replaced with new.  Supplied and replaced fuel pump relay and tested fuel pump and wiring. All ok.  Carried out further tests and found that spark being lost when hot. Checked coil pack and wiring. All ok. Printed off wiring diagram from Ford and found that a component that may need testing is an EDIS module.  Used etis and located EDIS module and using IDS carried out further tests, found trigger signal being lost using oscilliscope.  Trigger generated by CKP (crank sensor) Sensor breaking down when hot. Removed aux drive belts to gain access to CKP.  Supplied and replaced CKP sensor, replaced aux belts, hooked up IDS, clear fault codes from memory. Test drove.  All ok."

I'm just amazed that a Ford garage took so long to trace the fault and that they seem to use a process of elimination, changing components (which I have to pay for) until they arrive at the correct one.  I thought modern diagnostics were cleverer than this.

Anyway, I'm back on the road, with my wallet £900 lighter..... >:(

Title: Re: Misfiring Ultima Cosworth
Post by peteHull on Jan 31st, 2008, 3:33pm

on 01/31/08 at 10:21:41, georgeodyphotos wrote:
Hi guys, At last the problem is sorted! For your information I will copy what is written on my invoice from Ford garage. "Hooked up IDS and carried out DTC check. No fault codes listed. Test drove and vehicle cut out numerous times. Re hooked up IDS and fault codes PO171 and PO174 bank 1 & 2 lean mixture. Using DAT logger unable to test fuel pressure regulator/ fuel pressure.  Spoke to Ford technical and was advised to clean up all electrical connections and tighten all air hoses/pipes. Ford technical advised fuel pressure regulator be replaced (part No: 73346840) Supplied and replaced fuel regulator valve, found air intake pipes split when dismantling. Ordered pipes and replaced with new.  Supplied and replaced fuel pump relay and tested fuel pump and wiring. All ok.  Carried out further tests and found that spark being lost when hot. Checked coil pack and wiring. All ok. Printed off wiring diagram from Ford and found that a component that may need testing is an EDIS module.  Used etis and located EDIS module and using IDS carried out further tests, found trigger signal being lost using oscilliscope.  Trigger generated by CKP (crank sensor) Sensor breaking down when hot. Removed aux drive belts to gain access to CKP.  Supplied and replaced CKP sensor, replaced aux belts, hooked up IDS, clear fault codes from memory. Test drove.  All ok."

I'm just amazed that a Ford garage took so long to trace the fault and that they seem to use a process of elimination, changing components (which I have to pay for) until they arrive at the correct one.  I thought modern diagnostics were cleverer than this.

Anyway, I'm back on the road, with my wallet £900 lighter..... >:(


What an IMPRESSIVE account of actions, maybe it could be said it warrants the £900  ??? I wonder.....
:-/ Pete

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Jan 31st, 2008, 6:01pm
P.S. That £900 did include  the discs and springs that I mentioned earlier.  But even so, a big bill, having recently paid £300 for a service, £232 for headlamp(fitted) and £250 for waterpump back in October.
George.

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Feb 1st, 2008, 12:18am
Hi guys.
Guess what? The car was driving beautifully around town and then I went for a 10 mile drive this evening and the f.....g thing is displaying exactly the same symptoms as before.  I'm pretty angry now, having just parted with all that cash.  Before I go legal, does anyone know if the garage are still responsible, having taken my cash and the problem is not cured?

At my wits end now. :'(

George

Title: Re: Misfiring Ultima Cosworth
Post by georgeodyphotos on Feb 11th, 2008, 5:48pm
Hi Everyone. Well, it really is fixed now. After the garage fitted all those bits without curing the problem, they "discovered some wiring that was brittle and probably shorting out". They have supposedly replaced the wiring and the car now runs properly.  An expensive visit  (£930 ) and I wonder how much could have been saved if the wiring had been spotted at the beginning? Just have to hope that nothing else goes wrong for a bit.
Anyway Guys, thanks for all your help and suggestions.
George.



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