Non-starting

[AcemanToo]

Have now got a further problem - the car refuses to start! Got trailered home on the back of an AA truck a couple of weeks ago. AA man said the ignition control module was faulty. Got a new one and fitted it but no joy. Fitted a new engine management control unit (had one spare) but that didn't do it. Called in a mobile car electrics man who reckoned it was a faulty coil. Replaced the coil with a new one and it started first time. Also have new leads, rotor arm and distributor cap fitted. Starting got progressively worse and now I'm back to square one with the car not starting at all. On trying to start, the engine sort of coughs once and turns over easily on the starter motor but nothing more. Any ideas on what I now need to look at? The car is a 1995 model, DE 1034 with the injected 302 engine. Many thanks for any advice![:)]

[B.P.Bird]

Patrick, an annoying situation I do sympathise. It seems that the new coil initially cleared the fault so perhaps this is the area you should start on ? Possibly the old coil expired from old age and the new coil is the wrong type or faulty ?

[DGoose]

Hi Patrick,
   
   It seems likely that you have an electrics issue as presumably the people who've suggested ignition modules and coils have good reason to do so but I had a similar problem with DE1017 earlier in the year which turned out to be a sticky fuel pump, probably down to lack of use over the winter.
   
   May be way off the mark but the pumps are in a pretty exposed position and they are now getting on a bit, also worth checking filters as these tend to get ignored.
   
   Let us know what you find.
   
   David

[AcemanToo]

Many thanks to you both for your ideas! The strange thing is, once the car has started (if it does) it runs like a dream with no misfires or hesitation. The coil and other parts are all correct for the engine - supplied by the most helpful American Car Parts - strongly recommended for good prices and quick service. I'm going to have another go at the car tomorrow - new fuel filter (changed it about five years ago) and also a check on the pump on the petrol tank. Although I can hear it pressurising the system,maybe there could be some fuel blockage, partial or otherwise. I'll let you all know how I get on. Is there a diagnostics port on the car do any of you know? Once again, all help and ideas gratefully received!

[Max Allan]

Is the car fitted with Cobra immobiliser? I knew of someone with an Ace that developed starting problems. Fault was ultimately traced to the immobiliser.

[Max Allan]

Next time car won't start pull off a plug lead, connect to any spare plug you have lying around, earth out plug body on earthed metal component of engine (A/C pump springs to mind) and get someone to crank engine. If plug can be seen to be sparking then fault is on fuelling side of things. If no spark fault lies with ignition.

[AcemanToo]

Hi Max,
   
   Tried to start the car this morning but still no success. I fitted a spark tester between one of the plugs and the appropriate lead -result, erratic spark, every now and then a really strong one, a few weak ones, then no spark at all then a strong one etc etc, no pattern to the interval between sparks i.e. no sign of a regular spark. The leads, plugs, distributor cap and rotor arm are about three thousand mles old,and two years old at the very most, the coil, ignition control unit and engine ecu are all new. I've got a brand new set of leads, distributor cap and rotor arm to fit as a final attempt, but, if it starts, the car runs without missing a beat so it's unlikely to be the last three items causing the problem. I can only think that there's an intermittent short somewhere in the ignition circuit but I can't see any signs of rogue sparks or flashes from anywhere on the engine. I've checked inside the distributor and the electronic ignition looks ok with no sign of arcing or burning. I've got a mechanic coming on Tuesday or Wednesday to run a full diagnostic check on the circuits and components so hopefully he'll be able to fix the problem. I need to know if there is a diagnostic port and where it is located before then. Hopefully the combined expertise out there will know![:)]
   Regards, Patrick.

[Flyinghorse]

Have you checked the ballast resistor is ok?  This can give ignition non starting issues like you state.
   
   Graham

[AcemanToo]

Hi Graham,
   Thanks for that - I didn't even know it had a ballast resistor! Where will I find it on the car? Is it the small alloy cylinder with one wire coming out of it next to the coil? Or is that just a suppressor for getting rid of interference on the radio?
   Cheers, Patrick.

[Flyinghorse]

My CRS has a ballast resistor near the coil. Its a small oblong(6cm long) & buff coloured. It can have nut terminals or spade.
   
   
   
   
   It reduces the voltage to the coil.

[hawk289]

You may not have a ballast resistor, modern cars have this within the coil or the loom. What may be the problem is the ECU or sensor for the engine management system.

[Max Allan]

Aceman Too. I assume you are referring to diagnostic plug on ECU? If so I'd like to know where it is myself, because for years I've had an irritating problem with engine stalling when selecting drive (auto box).
   
   You didn't say if your car has the Cobra immobiliser? Your problem sounds very similar to the problem my mate had - his Ace would run fine, but then refuse to start. If you've got an immobiliser my first move would be to disconnect it.
   
   Problem with test equipment it introduces another unknown. Personally, I'd use a spare plug (any type will do) and start by pulling the central HT lead on the distributor cap and connecting it to the spark plug with body earthed to a substantial metal component on engine in order to ensuring good ground connection (hold plug in place with something non-metallic). Ignition is OK if cranking engine produces continuous stream of sparks that can be both seen and heard. If spark is erratic (as you found with tester) then fault lies with coil or other "upstream" component. If spark is good, repeat exercise connecting slave plug to a spark plug lead and see if you get equally strong regular, but fewer sparks. If spark is weak or erratic check cap and rotor.
   
   Hope this helps and apologies for being long-winded.

[Nev]

There is an ecu  diagnostic plug on the near side,  under the bonnet, at the bulkhead, where the ecu is, it is rectangular, and hs a second small one with it.

[AcemanToo]

The mystery deepens! Having now fitted another new coil, the non-starting continues! A meter across the + and - connections on the coil gives a constant 12 volts with the ignition on. A spark tester fitted to the king lead produces a strange result - on cranking the engine there are two initial good sparks and then nothing, but, when you stop cranking, there is a final good spark as the ignition / cranking is turned to off. I've substituted the original ignition control module for the new one and still get the same result, two good sparks then nothing no matter how long you crank the engine, and then, on turning off the ignition, a final, single, good spark. I can't find any mention of a ballast resistor or a capacitor in the Ford Mustang workshop manual and neither have we found any sign of a diagnostics port. There is an engine run relay in the central fuse box behind the dash but substitution doesn't make any difference. The engine management IC is new but replacing the old one makes no difference - the symptoms remain the same. All fuses are good (last resort stuff now!) but I'm running out of ideas. Could it possibly be the ignition switch itself? All ignition type wiring and plugs look sound and all contacts appear good. Thank to everyone for their ideas so far! The original alarm system (FoxGuard) was replaced about 7 or 8 years ago with a Toad alarm. Any ideas on whether that could be the problem? I can't even tear my hair out because I haven't got any.......

[Max Allan]

Unlikely to be the cause here, but a battery that's not man enough for job can cause a weak or non-existent spark when cranking because all battery output is taken by starter motor (hence good spark as key is released). A poor engine/chassis earth can have same effect.
   
   
   You said an electrician was coming last Tuesday/Wednesday...?