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        General >> Problems >> Cosworth 24v still cutting out
        
(Message started by: cobrascim on May 25^th, 2023, 12:55am)

Title: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 12:55am

So having renewed all the wiring to the engine and gearbox and also taking the opportunity to make up new front stainless exhaust pipes I took the car a blast along the road and back. What a difference! The autobox was using all the gears and engine really was running well. I parked the car up back home and after about 30 mins the engine stuttered and cut out. It then would not start. It would go to fire but not stay started. When I walk away for a while to allow things to cool down(not that it was overheating) it would restart and run for about another 20 mins and cut out. Really strange. I put a fuel pressure gauge on to monitor it and it stays pretty much constant near 40 psi which is about right. Diesnt die down when tryint to restart. The spark plugs are getting sparks from the coil pack so I'm now wondering if the positive feed to the injectors can be cut off by the EECV PCM. Would anyone know? I'm going to try and get a meter into the supply pin from bulkhead plug tomorrow and monitor it. I have changed R17 and all the other relays around it for a spare set I have to see if it would restart but it didnt. Did this one at a time but that's not to say that the spare was anygood mind you but at the moment I'm trusting them. I'm wondering if the cam sensor can cause this problem? The 12v engine doesnt have a cam sensor just the crank one for the EDIS so I dont really know why it has one. It is definately related to something heating up and then being ok once it cools down again.
Anyone any ideas? John.

Title: Re: Cosworth 24v still cutting out
Post by brds on May 25^th, 2023, 8:52am

Cranksensor?

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 9:46am

The crank sensor drives the EDIS pack and I was getting spark at the plugs so I dont think its that. Although I checked it using 2 of those lighty up inserts to reach the plug in the head. I have a better in line tester coming from car builder solutions and will recheck that again. I ordered that when I went on to order one of the thermostats that fits our car. So back to troubleshooting today. :-/

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 2:56pm

Hmmm. So I couldnt get the car to cut out in the driveway today to get to the failure point to start fault finding. The only things I have done are to rattle the fuel pump inertia switch around and to through connect a toggle switch that the previous owner had introduced to the fuel pump line as an inhibiter. I also disconnected the negative terminal of the battery which I dont normally do -just the positive as I do have a battery drain issue after a few days. I ran car for 50 minutes there and it didnt cut out.
I had unplugged the lack bulkhead connector to find out which wire was pin 38 to find the positive feed to the injectors as I thought maybe this gets cut for some reason but on just having the ignition on only the feed to injectors is always there as well as to the coil pack. So will try again a bit later.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 3:36pm

You honestly couldnt script this. Went out to restart the scorpio and wouldnt start. So I'm now at least where I wanted to be - in fault mode. Fires but wont actaully start. Feed is there to injectors and coilpack. ???

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 5:35pm

Swapped over the cam sensor for a spare from my other engine. Not that. Started but then cut out. Wont start now.

Title: Re: Cosworth 24v still cutting out
Post by Tompion on May 25^th, 2023, 8:03pm

Since you say you have a battery drain, how much old loom do you still have? Typically faulty wiring to the engine fans can cause a drain - they may even come on randomly with ignition off.

ABS loom has some permanently live wires that can cause a drain if the loom is failing.

I think the ECU just controls the negative side of the injectors.

Did you replace the 3 core shielded wire between the ECU and the EDIS?

The ECU can cut power to the fuel pump if certain conditions aren't met.

I had a problem with mine refusing to start last year on one of those really hot days - after just moving onto the road whist I worked on my other car.
My feeling was fuel pump so tried connecting direct from the battery to the pumps plug in the boot and earthed it locally, I could hear the pump running & the car started no problem. When I got back on the drive I took off the temporary wiring and re-connected the pump connector - it started again without problem. Sadly no longer my main car and I haven't looked into what the problem is.

The cam sensor gives more precise firing of the injectors. Can't comment on the 24v, the 16v will run without it connected.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 8:26pm

Hi T.
Thanks for your reply. This is really starting to do my head in after putting in so much work on this thing.
I only rewired to the 2 bulkhead connectors C110 and C112. So rest of the loom is as was. I renewed the wires from the coil pack and crank sensor directly to the EDIS module rather than go through the plugs for fear of what may be in the main loom. That way the new wiring would always run the engine at least in limp home mode if the PIP and SAW wires going to the PCM were problematic. This does not seem to be the case mind you.
I only renewed the damaged part of the 3c wiring near the EDIS module down to where it went into loom. I had to get the loom opened up to ensure I got to a good still insulated piece. I have had the car up and down the road so the PCM is definitely getting the timing signals to and fro.
I to suspect fuel as issue but my pressure gauge shows around the 40psi mark which is pretty much correct. The fuel pump does run but I'm wondering if the power is getting cut as you say by PCM and does it stop firing the injectors also? which would mean that the fuel rail would just hold the fuel pressure? I f the pump were to stop and injectors still fire then the pressure in fuel supply would drop which it isnt.
I will look into your suggestions for battery drain next once I get to the bottom of the cutting out issue.

Title: Re: Cosworth 24v still cutting out
Post by Tompion on May 25^th, 2023, 10:42pm

You could try putting a small amount of petrol directly into the intake - about a teaspoon, if it fires and stops you'll know the injectors aren't firing.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 25^th, 2023, 11:19pm

Ha. I used to do that down the old carbs back in the day. ;D

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 26^th, 2023, 7:52pm

on 05/25/23 at 08:52:32, brds wrote:

Cranksensor?

Hi brds.
I'm sooo hoping you are correct. I have just changed over the cranksensor from the one off my spare engine and car has just been ticking over for half an hour.What an awkward b* to try and get the top bolt back in. I now have my fingers crossed and will test drive it locally for a while.
Presuming when these crank sensors fail its the engine heat that causes them to stop working when they are "degrading". i was getting a quick fire of the engine which I saw at the plugs so presumed it was ok wrongly! I hope. Time will tell and will post up findings.
Thanks ;D
John.
PS Can you still get this sensor? Be handy to have another working spare methinks.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 27^th, 2023, 10:36pm

Well today I took the pick up an 11 mile run over to one of my mate's house. Cuppa and then 17 mile trip back via a different route with no hiccups. Could this be cured? ;D I do hope so. The new wiring which needed done anyway has certainly got the gearbox operating superbly and the car really wants to be let off the leash :o

Title: Re: Cosworth 24v still cutting out
Post by brds on May 28^th, 2023, 8:27am

Good news, hopefully you're all OK now. These sensors are prone to heat as they get older. My brother had one fail on his Megane and I've seen other motors reported with same symptoms.
There's various Scorpio ones on ebay so should be available.
Bob.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on May 28^th, 2023, 4:11pm

Hi Bob. hopefully that's it thanks. I cant find the crank sensor mind you as it is all part of a bracket with 2 bolt holes and a third locating pin to get it to line up properly. doesn't seem to dismantle so this could be a future problem. Before this one gives up the ghost I will need to make a locating bracket with clamp and use a mondeo equivalent or such methinks.
John.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Jan 30^th, 2024, 2:03pm

So after thinking I had cured this problem I was about 1 mile from home 2 weeks back and the car rolled to a halt. I managed to get it fired up with misfires etc and got it within 500m of house and had to tow it the final stretch.
This may be a new/different problem but may well be the same again with crank sensor. Anyway when the car cut out before it always started the following day and ran for about 30 mins. I left it for a few days and went to start it but had to charge battery as the starter was just clicking. Anyway after charging the battery the car would not start. It would try to fire but not run. I then went out a few mornings later and it started without me doing anything. I just wanted to move the car round the back to my garage which I was able to do.
During the engine rewire I ran the fuel injector firing wires to the back of the engine bay to allow the LPG ECU to be wired inline to each injector. I have had a sneaky suspicion that the LPG ECU could be an issue so I have removed it from the wires until I can confirm the car runs for a while ok.
The LPG system would switch back to petrol sometimes during running(usually on overrun when lifting off throttle) and one of the areas I need to rule out is whether the LPG injector switches (whether small relays or electronic) inside the ECU is allowing the feed back through to the petrol injectors of going high resistance. What I'm doing will tell me that if the car runs ok.
Anyway just a wee update as I finally have a bit of reasonable weather to get out and work on the blooming thing. Will update soon.
John.

Title: Re: Cosworth 24v still cutting out
Post by szinyei on Jan 31^st, 2024, 1:51pm

ECU loom new? My 2.0 16v is probably some of the last mohicans around. Until I do not get it fixed, i.e. completely new wires and a tolal ECU loom rebuilt, I doubt that it will work properly…the nearest chap doing rebuilt is in Poland…noone wants to do the complicated job in Germany…

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Feb 1^st, 2024, 2:50pm

on 01/31/24 at 13:51:03, szinyei wrote:

After replacing the engine and gearbox looms to the engine bay square connection plugs (and bypassing these plugs for direct wire to the Edis module, crank sensor and coilpack) the only existing wiring to the ECU for engine running purposes is the PIP and SAW wires from the edis module. If these failed then I would at least drive home in "limp home" mode. I can understand no-one wanting to rewire the car as to do it properly it would really need the engine and gearbox out the car. Not quite at that stage yet. John.

Title: Re: Cosworth 24v still cutting out
Post by Jackattack2002 on Feb 4^th, 2024, 4:27pm

The crank and camshaft sensors (or the wiring to them) is where I would focus on first. But what are the symptoms of the non-start ........ is the engine trying to fire or is it just turning over. I had a similar issue a while back with my 24V and it turned out to be PATS related. The key had lost the code sync and so PATS wasn't firing the injectors. Fired first time with the red master key. If non of the injectors are firing, I wold focus on ECU/PATS

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Feb 6^th, 2024, 12:24am

Thanks JA. Weather is not good at the moment to take car out for a run and it is starting every time now which makes life difficult to fault find. The non start after leaving it sit for a few days was that it would try to fire but not run then after another few days it started. Just reading up on the pats system as you suggest and I will ensure it isnt it. I may have 2 faults possibly. I'll report back my findings.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Feb 26^th, 2024, 8:15pm

I dont believe it! Finally got some time and good weather and decided to tackle this issue. I hooked up fuel pressure gauge throughout my testing and the pressure remained as it should. I suspected the crank sensor again so hooked up an oscilloscope directly onto the sensor after it had cut out and the signal was perfect so it wasn't that. Not so sure that my last sensor is actually faulty(I still have it and will test it this time). Previously when the engine had cut out I had used spare coil pack and EDIS module and the car did not start so that's when I suspected the crank sensor or my new screened cable down to it via the original path. Anyway this time around I was starting to suspect my new wiring to crank sensor. This was after chasing possible relay 17 probs and feed to fuel pump, injectors, EDIS and Coil pack. All seemed fine.
I dont know why but went and got my EDIS module off the scimitar again and plugged it into scorpio. Thing started. Let it tick over and went beyound normal cut out time. unplugged and put wiring plug back onto scorpio module started the car and had it ticking over for an hour in driveway with no hint of cutout. During this time I was wiggle testing everything with no issues. I thought to myself this issue surely cannot just be down to plug into the EDIS becoming loose or dirty and connection going down but it seems so far to be exactly what it has been. The plug on to the EDIS is missing half of its clamp that holds it in place but I think I will be cable tieing this on.
Road test locally today went ok and more local road testing to be done.

I dont like where the EDIS is positioned below the water bottle and might move it up to somewhere easier to access for testing etc. It means lengthening the wiring but that is easily done. I wonder now whether this was my issue after rewiring the engine and box instead of crank sensior. Maybe not mind you as after fitting other one it started. OH ACTUALLY! While I'm reflecting on this _ It may have been a bad/faulty connection at crank sensor and with me pulling lead off to put my test leads on and then plugging it back on again has made a better connection. It does get very dirty around that area.
John.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Feb 26^th, 2024, 8:22pm

The more I am thinking about this I am now suspecting the connection to the crank sensor is/was the problem. With changing the sensor last summer and plugging onto the spare one it will have made a clean connection at that time. Lasted til now to fail again. Then with me unplugging for test and putting car wiring plug back on I have made connection good again. If the happens again I know exactly what to unplug and replace. I think some dirt must be getting into it. After all it is at the bottom of the engine and I do still have my undertray off it since last summer.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Mar 14^th, 2024, 11:35am

Well engine cut out again. But another thing that has been on my to do list for a wee while now after rewiring all the engine and gearbox looms abd local wires to EDIS etc. was to run a new 4 core screened cable from the EDIS to the PCM (EECV). Seen on a lot of the older posts that this part of the wiring is also important as the loss of the PIP signal to PCM would make it think the engine wasn't running and stop firing the injectors. When chasing my fault I was going between thinking it was a fuel problem then an electrical problem and I think it has been misleading me a wee bit with the characteristics of its failure. I think faults on the old screened cable would cause the engine to cut out due to shutting off the firing side of the injectors and probably fuel pump/relay. I have done 3 short runs of around 7 miles (to build up confidence) and the only issue I have is that my rev counter has stopped working. I still have the bottom of the dash off at the moment and need to investigate this issue now. I'm not surel if the rev counter is driven from PCM or there was a splice off the PIP wire on the old screened cable that is no longer in use. I shall find out but I am hoping this has finally put the cutting out issue to bed. Will report back.
John.

Title: Re: Cosworth 24v still cutting out
Post by cobrascim on Mar 28^th, 2024, 10:31am

Built up confidence in car running around locally and took it through to Edinburgh and back yesterday. 150 mile round trip in the rain and slush with lpg re-connected also and car ran brilliantly. Looks like I finally have cured the cutting out problem. Might go back and change the crank sensor back to old one just to check it. Might get lucky and it could be fine seeing as you just cant get them from anywhere. I'll get round to doing the rest of the engine bay chassis loom from the lower sections of plugs C110 and C112 during the summer months.
John.