Technical '94 Tipo 1.4ie ignition problem

[RayMK]

My son bought the '94 Tipo 1.4ie about 10 years ago. 3 years ago he sold it to a friend who was in need of a car, then 9 months later I bought it off the friend because it needed a fair amount of MOT work which no one else was prepared to pay for. It has only done about 60K miles. The MOT work was duly done and the car continued to work reliably until mid July this year when it failed to proceed. I had driven into the local countryside with all systems working properly, as they had been doing throughout our ownership. I parked at a scenic spot in wonderful weather and settled down to eat a packed lunch and read a Practical Classics magazine. After about 2 hours I decided to head home. I operated the ignition key in the normal manner and the starter turned the engine completely normally but, instead of firing pretty much instantly as it always had done, it just continued to turn without so much as a cough. I tried again three or four times but nothing changed. It simply did not want to fire. The car's tank was just over half full of recent petrol and it has been regularly serviced throughout its life. I investigated under the bonnet, looking for broken wires, loose connections, leaks and anything else that was broken or displaced. Everything appeared to be fine. I pulled a sparking plug to test for sparks. Absolutely nothing. The AA was called. They turned up within 1.5 hours and conducted basic tests which confirmed the lack of sparks but that the coil was receiving 12Vdc and the crank sensor was pulsing. The car was mounted on the AA dolly and taken to a local garage for investigation. I was happy for the garage (which I know well and trust) to treat the Tipo as a fill-in job. I've got another car, so no bother. The garage replaced the coil with the correct Fiat part but this had no effect on the symptoms i.e. the engine turned over on the starter but did not even cough and there were no sparks even at the king lead, as before. My Tipo has the Digiplex ignition with distributor in line with and at the right hand end of the cam cover (looking from the front). It has standard single point fuel injection. My manual mentions an ignition module fairly close to the coil and battery near the right headlight or inner wing. I can't see any such module or indeed any loose wires if the damned thing had gone AWOL. This makes it difficult to replace!! The main Digiplex box is on the bulkhead/firewall but looks nothing like the absent ignition module. Any comments would be most welcome. I, and my garage, have drawn blanks trying to diagnose the lack go sparks. I may have to get the car taken to an Italian cars specialist or possibly a Fiat dealer after further phone calls to give me confidence that these options may unravel the mystery.

 

[bugsymike]

Engine code 160 A1.046 ?
Many manufacturers around that time used a sort of booster module often fitted to the side of the distributor (roughly the size of a matchbox) to take the signal and boost it for the coil, Fords especially would pack up and companies like Intermotor would do a cheap replacement. I am not familiar with Digiplex. Another type used on some Ford Fiestas etc. was a box with a vacuum advance pipe to it , usually fitted to the bulkhead which did away with the distributor all together. Somewhere in my garage I have one of those. If you can still locate one of those or similar and have a good impulse from the crank sensor it may be possible to operate the coil that way. I assume you don't still have the original ignition parts from pre the "Digiplex" setup?
I have just found this final picture from an old Haynes manual showing location of "Digiplex unit" I thought from your thread that it was a sort of "aftermarket" addition though according to the Haynes it was only on the 1.6?
Seeing in your thread about reading "Practical Classics", I had a Vintage lorry in their commercial section in 1987, a bit of useless information.
If this is any good let me know.

 

[RayMK]

Engine code 160 A1.046 ?
Many manufacturers around that time used a sort of booster module often fitted to the side of the distributor (roughly the size of a matchbox) to take the signal and boost it for the coil, Fords especially would pack up and companies like Intermotor would do a cheap replacement. I am not familiar with Digiplex. Another type used on some Ford Fiestas etc. was a box with a vacuum advance pipe to it , usually fitted to the bulkhead which did away with the distributor all together. Somewhere in my garage I have one of those. If you can still locate one of those or similar and have a good impulse from the crank sensor it may be possible to operate the coil that way. I assume you don't still have the original ignition parts from pre the "Digiplex" setup?
I have just found this final picture from an old Haynes manual showing location of "Digiplex unit" I thought from your thread that it was a sort of "aftermarket" addition though according to the Haynes it was only on the 1.6?
Seeing in your thread about reading "Practical Classics", I had a Vintage lorry in their commercial section in 1987, a bit of useless information.
If this is any good let me know.

Thanks for your reply and attachments. The engine code should be as you've quoted but the car is a few miles away so I can't check right away. The Digiplex is indeed a completely standard set-up, not aftermarket. Most photos of the 1.4ie engine show the earlier distributor and a different ignition system and I agree it is usually only the 1.6 which is shown with the Digiplex and cam end distributor position. My manual (digital copy found on line) is a bit ambiguous on what is fitted to the late model 1.4ie. We bought the car 10 years ago with about 37K recorded, in good used condition with a completely undisturbed engine unit which certainly behaves like a 1.4. In the early 2000s my late wife owned a 1.6 Tipo, so I'm fairly confident ours has not had an engine swap. Yesterday, on visiting the garage, I was surprised that I could not find anything that looked like an ignition module where the manual said it should be. I took a few photos (attached) but may need to go back on Monday to take more, particularly the area to the side of the battery where I may have missed something.

Nearly all 'classics' interest me. I've owned a 1961 Reliant Regal MK6 since 1992. It is still roadworthy but for various reasons rarely gets out these days.

 

[bugsymike]

Your Digiplex photo looks very similar set up including vacuum advance built in, to the Ford Fiestas of that era and by and large, I think it was standalone apart from the pick up sensor and the distributor and rotor arm to direct to individual plugs.
According to the Haynes manual the 1.4 had the module on the side of the distributor like some of the older Ford Escorts etc. and often failed misfiring, but the 1.6 Tipo had it on the bulkhead like yours, so maybe it was a changeover to the more improved version.
The hardback manual (1625) I have is only for vehicles 1988 to 1991 but from my experiences with the Fiesta system in the past it does point towards that Digiplex unit in total failure whereas at the time the earlier versions of Ford ones gave a misfire more commonly.
The Digiplex being a sealed unit not a DIY repair part replacement only if obtainable. I don't know if anyone on Forum has a spare one or the details of readings to test it.
Re the Reliant, in the late 1960s I had a friend who was foreman of the local Honda motorcycle dealers who were also Reliant agents and the boss had an early Reliant with the Girder front forks etc.
This is the Ford version with vacuum advance.

 

[s130]

Attached is info on the Digiplex ignition systems and some diagnostic information.

I've had the crank sensor fail on our 130TC because the sensor wire is clamped to the block and the block heat causes the wire plastic to become hard and brittle.

Suggest you read and test accoring to attached file which includes sensor testing.

 

[RayMK]

Attached is info on the Digiplex ignition systems and some diagnostic information.

I've had the crank sensor fail on our 130TC because the sensor wire is clamped to the block and the block heat causes the wire plastic to become hard and brittle.

Suggest you read and test accoring to attached file which includes sensor testing.

Many thanks for this. It helps me to understand how the system works and the testing instructions will help either me or an appropriate garage technician to diagnose where the problem is. I'll probably have to delegate most of the work because age, health and mobility are ganging up on me. Provided that the Tipo can be sorted out at reasonable cost, I do not want to scrap this car.

 

[jonti]

regarding your updates elsewhere, I have the eu scan software and correct lead to read my 1.6 i.e. If it becomes necessary I could see what could be done to assist. However I would say this diagnostically is probably a last resort after the other diagnostic tests suggested.

 

[RayMK]

Not much progress on my Tipo. We found and bought a known good Digiplex 2 ECU (439M) which is the same as the one on the car. Fitting this did not change the lack of sparks. I've bought a NOS Magneti Marelli SEN8M crank sensor but have not fitted it yet. The car is still at the garage and the battery has now gone flat which means I need to either bring it home to charge or fit a temporary good battery in order to carry out diagnostic tests on the ignition system with a multimeter. I did attempt to do the tests a few weeks ago but with only 3.4V left in the Tipo's battery I could not complete them.
A couple of days ago I made enquiries with a local Fiat specialist to see if they'd be willing and able to get the car fixed. They have not yet got back to me. I have not given up but everything is taking ages!