Any of you mechanics had this in the past?

[Flapdisk]

I'm pulling my hair out on this one. We have a 1997 Ford Escort LX it's only done 47 thousand and is immaculate, was my wife's dad's car and came to us when he died a couple of years ago.
My wife likes to use it because it was her dad's.
Now then, it will work perfectly for weeks, then suddenly it will not start, no matter what you do it will not start, not even a twitch or attempt to start, it will spin over fine on the starter, just won't fire. It is a new battery. so far it's always happened when she is at work or when it's most inconvenient for me to do anything.
This is the kicker, if you leave it, 30 minutes later it starts first attempt as if there was never anything wrong with it, I am trying to prove if it's spark or fuel, but so far every time I have taken a lead off and held another plug to metal, it starts!.
I have cleaned every single plug on connector under the bonnet with electronic switch cleaner.
I have checked the inertia switch has no loose connections and the reset button is fully in.
I have wiggled all the fuses in case of a dirty connection. still does it.
I will eventually catch it and see if it's spark or fuel, but I just wondered if any of you have had this in the past? and could save me hours faultfinding.

 

[BrokenBiker]

my 98 fiesta had a similar thing after i crashed it. Was the fuel cut off switch located underneath the interior trim under the passenger door. It was broken and would occasionally cut all fuel to the injectors then all of a sudden it would work again. Changed this and it was fine

 

[johnik]

but so far every time I have taken a lead off and held another plug to metal, it starts!.

that used to be the sign of a weak spark (coil or leads) or dodgy spark plugs.

 

[Rocketman]

Could be 100 things. The joy of fault finding.

So does it stink of fuel when it doesn't start?

 

[BrokenBiker]

if its a 97 model it would be before obd2 so should be fairly old school to find the fault

 

[Flapdisk]

@brokenbiker Hi mate, I did say in the post I checked the inertia switch, but not replaced it, the car has had no knocks to trigger it, but if I prove it is a fuel problem I may bridge it out to prove if it's faulty or not.

@johnik That's right, on the old bangers with distributers, points and carbon leads, this is twin coils electronic ignition. But I wasn't saying it would start because of that, I was pointing out it would start anyway, as it does if you leave it for a bit so you can't catch it to see if the spark is missing.

@Rocketman I know, that's why I was hoping someone had, had this before, to save me checking 100 things.
Nope no smell of fuel mate, it's fuel injected and I don't pump the throttle like a loony when it won't start.

Thing is though, when it starts, it never stops or lets you down on a journey, it's only when you go to start it from standing and also don't forget it only happens maybe once in a month, so something is intermittent, but not so bad it constantly causes problems, something causing a weak spark would show more ofter I feel.
Do these modern cars with an ECU and all the sensors still have a switched ballast resistor in the ignition?

 

[J.B. Welding]

I had bother like that with my escort, it was a dirty flywheel sensor (don't know the right name 4 it), it was a bit loose too. Cleaned and tightened it back up end of problem. Good luck matey.

 

[mike 109444]

Think you should hear the fuel pump run for a few seconds to pressurizer the fuel injection system when ignition is turned to 1st position in readiness to start. Ask wife to listen for that when it does not start. Get her to hear it when it operates normally so she knows what to listen for.

 

[the snooper]

first thing to work out is it temperature related, note the outside temp when it fails to start, when it does fail to start try to push start it, have had a similar problem once it started it was fine the rest of the day unless it was really cold, turned out to be the starter motor windings had gone and when they contracted due to temp they shorted and took all the power away from the ignition system, replaced the starter motor and all was good

 

[the snooper]

also if I remember wasn't this year of escort notorious for badly soldered fuse tray, ive soldered a few of them up mainly lighting faults, they do come apart just make sure you know where everything goes should you go down this route

 

[Flapdisk]

@ JB thanks mate I will check that, if I can find it :-)

@ Mike good point mate, thinking about it I can't ever remember hearing it, but I will make a point of it and make sure I can hear it when it's starting ok so I know what to listen for when it doesn't.
@ Snoop valid point mate, already thought of it. It did it a few weeks ago when it was covered in snow and ice and it did it yesterday in the sunshine.

Edit: Didn't know about that one snoop. I was astounded to find they have put the fuse box on the panel under the steering wheel and if you want to get at the relays you have to strip it all out! It's really tough for me to do low work like that these days after various surgery and blood arthritis!


Couple of good points to check there, keep em coming guys :-)

 

[Wendelspanswick]

Have you checked the oil level, we had a Daihatsu Charade Gxi of a similar vintage and the same problem, turned out to be the oil level was low enough that when we parked on our sloping drive there was not enough oil pressure to work the hydraulic tappets so the valves were not opening.

 

[Flapdisk]

Wow! that's a good one Wendel mate. I hadn't but I will :-) Hmmmm why would it start ok after 30 minutes or so of trying though?

 

[keithski122]

Is it a zetec engine?
Could be the incorrect grade engine oil, I remember a few having poor starting when the oil was too thick.

 

[Mick - Ford Focus]

Had Exactly The Same Problem On My Escort Mark 3.

Mine Took Some Finding - Many Sensors Checked And Cleaned, Much Scratching Of Head.

Finally Put It Down To Dirty Flywheel Sensor ( Seem To Remember A Bit Of B**ger To Get At) ((See Above J B Weling))

AND A Totally Dry As In Empty No Water/Acid in The Battery.

Went On For Months With It.

M

 

[rikrobson]

My mates audi needed a crank sensor. As tocwhy you need a crank sensor to start a car is beyond me. But the designers seem to want it. Also my experience of focuses has been the coil pack. Had a mondeo one that would not start it it was a bit damp. Not good in Scotland. An old reader should identify the problem though

 

[the snooper]

it not going to be the hydraulic lifters they retain their position long enough for oil pressure to build, if they didn't the engine would rattle badly each time the engine started, even with no oil pressure the engine would still start and run albeit badly and noisily

 

[Mick - Ford Focus]

Mine Was 1.8 Zetec Engine - Not OBD2 BUT Could Get "Flash" Codes Out Of The ECU With Some Wires And A LED - It May Help You. Haynes Engine Code Book Helped Me With That One.

M

 

[the snooper]

Have you checked the oil level, we had a Daihatsu Charade Gxi of a similar vintage and the same problem, turned out to be the oil level was low enough that when we parked on our sloping drive there was not enough oil pressure to work the hydraulic tappets so the valves were not opening.

you may have had a low oil sensor, the lifters don't close up enough to stop valves opening

 

[piman]

Hello Rik,

"As tocwhy you need a crank sensor to start a car is beyond me."

I only play with old cars but isn't the crank sensor the datum for the ECU to set the ignition timing?

Alec