MGF runs only for about 2 seconds??

[djpeteferg]

hi all,
wonder if you could help. we have just bought a 1996 vvc as a none runner, and someone might be able to help diagnose the problem

the car has been stood for a year, according to the guy i bought it off (who seems very genuine), he started the car every week for 10 months but two months ago it failed to start (about the time that he removed the battery to charge it).
the car fires for about 2 secs, but fails to continue running.

the key fob appears appears to be doing what it should, it locks and unlocks the car, if you turn the ignotion with out "plipping" the button, the buzzer goes off inside the car. and the indicators also flash when you open it, but even when you loch the car the alarm light never actually lights up on the dashboard?

also, following using the keyfob, and turning the ignition the indicator relay under the dash continues to tick very erraticlly, this leads me to think that there is an immobiliser issue.

I have checked other certain things though which dont seem to tie in, like, if you crank the engine there is a spark at the ht leads, and the fuel pump operates on ignition, and during cranking.

do these cars shut everything down when immobilized? or does it just no power the injector rail? thats what is throwing me!!!

i also have the emergency key code which i have tried, but it doesnt seem to work, and even after all the messing around with the alarm, not once has the horn gone off??

your thoughts would be very appreciated

pete

[bgunn]

Starting and then stopping a couple of seconds later is a classic sign of the engine management not seeing a code from the 5AS unit (due to a fault, or the wrong 5AS unit being fitted). If you keep cranking the engine after it stops, it won't fire again, unless you turn the ignition off for 30 seconds..

[djpeteferg]

do you know where the 5as unit is located? i have ordered a matching ecu, 5as and fob set, but dont know where the unit is?


pete

[Matt Parker]

The 5AS is located behind the centre console bolted to the underside of the heater controls. To access it you need to remove both side kick panels with the lights in, once removed you will see the 5AS upside down with a grey plug on the nearside and white plug on the offside, it is held in place with a 10mm plastic nut on each side.

[Rob Bell]

Here's a bit of pointless trivia that I've discovered on stripping down the Shed and starting to build it as a track car - there is, within the centre transmission 'tunnel' and under the centre console support bar, two holes, with captive nuts attached. Completely unused!

Bare with me here...

What is curious, is that the hole spacing is the same as that on the Lucas 5AS mounting lugs. Now that Shed no longer has a heater, the 5AS has no where to fix. To my delight, you can bolt straight here, with no modification to the wiring loom.

Almost certainly, this is where the 5AS was supposed to be mounted, but the position revised. One wonders whether this is related to reception which, as we know, is a bit marginal on the MGF.

Also, I wonder why the production process wasn't altered to exclude these bolts - surely these all cost money? Perhaps it cost more to delete it once the production tooling was put together???

Anyway, got that off my chest - and another one of those wonderful MGF trivial pursuit questions

[bgunn]

Nice, well spotted

It's strange they didn't remove the captive nuts, punching the holes is one thing, but still fitting the weldnuts is strange. I expect that as the body was tooled and made by an outside company (Car Bodies later Stadco), it'd cost more to change the spec for a minimal saving, if at all. I would say that if they were making the bodies themselves, Rover would probably have deleted the weldnuts!

[Stuart Dunn]

Hi,
I've had the same problem with an MGF I've recently purchased, However my alarm does seem to function correctly.
I have changed the rotor arm, plugs and dizzy cap to no avail.
In the end sat there feeling defeted I thought I'd try just a reset on the throttle pos switch, I performed this and no more problems, for the last three months its been fine.
Hopefully I haven't given the thing the kiss of death now but thought I'd mention it incase you may find it useful.

[djpeteferg]

thanks for that guys, afert waiting for the replacement ecu, i got bored and decided to remove the old alarm unit in preperation, only to find that the plug had come out of it!! fired up first time!!!

still i now have a spare set just in case

thanks again

[Rob Bell]

Now that's a result! I wonder how it fell out in the first place though? Odd...

[Matt Parker]

it is abit odd, the only way that could come out is by someone not plugging it back in correctly after having it out, as they have a fairly tough clip on them.