Wiring fault

[MarkTurbo]

I started my car this morning and it had a slight misfire + instead of the idle speed dropping from 1500 back to 1000 when its warmed up they were just staying at 1500.

I wiggled the airflow meter wiring about and it was ok then, drove the car to work ok. Started it again at luchtime and it had the same problem :evil:

I wiggled the airflow meter wiring about again and the car started spluttering then died and it won't start again now :evil: :evil: :evil:

I thought i'd try the ecu fault code test, but the engine managment light dosen't come on now when you turn the ignition on.

I've pulled all the covering off the loom to the airflow meter and around where it joins the main loom but i can't see any damaged wires.

Anybody got any idea's???

 

[zia]

it think you should one 12v live one earth one should be load wire with 5v going out/or in.

zia

 

[MarkTurbo]

I'll check that tomorrow on my test meter.

But i just remembered that you can disconnect the airflow meter plug when the car is running and it won't cause it to cut out. So i'm thinking its a problem further down the loom somewhere.

I've checked all the fuses in the fusebox and under the bonnet, could it be a relay?

It seems like theres no spark

The thing thats puzzling me though is, why dosen't the engine managment light come on with the ignition anymore?

 

[MarkTurbo]

Oh i forgot to add, one of the big fuses in the small fuse box on the battery side of the engine bay was blown.

It was the 25 A one marked ENGINE CONT. I've replaced it though but it didn't make any differance.

Don't know if this is anything to do with the problem or not :roll:

 

[zia]

the ecu need load input from air flow meter to start up or complete circuit
to tell what duration the injector should be open.once the engine is running you can normally disconnect airflow meter running because the ecu use throttle position of injector /spark duration etc. if your getting voltage to air flow check feul/and spark. was the check light coming on before?

zia

 

[MarkTurbo]

Cheers Zia, i'll check it out tomorrow.

The check light was working fine before :?

 

[Fast Guy]

The thing thats puzzling me though is, why dosen't the engine managment light come on with the ignition anymore?

Cos the bulb's blown :?:
It does sound like you have bad connection in there somewhere. Get a sparky to check it out if you can. Check the wiring into both connector plugs as I've problems from that on an ignition system before.

It might also be worth checking the ignition amplifier incase that's playing up.

 

[Anonymous]

I had the wiggle the MAF problem, however the ECU never reported a fault with it.

I just did what the FAQ sai and reground the MAF, never had any problems since.

Was amazed as well how much more economical the car is when the MAF is working properly.

Dan

 

[MarkTurbo]

The thing thats puzzling me though is, why dosen't the engine managment light come on with the ignition anymore?

Cos the bulb's blown :?:
It does sound like you have bad connection in there somewhere. Get a sparky to check it out if you can. Check the wiring into both connector plugs as I've problems from that on an ignition system before.

It might also be worth checking the ignition amplifier incase that's playing up.

The ignition amplifier is the small black thing just behind the coil isn't it? Do these ever pack up?

I got as far as checking the airflow meter to ecu plug wiring today, no problems there.

It seems like the ecu isn't getting any power. Is there any relays/fuses anywhere that i might of missed that would cause this?

 

[Fast Guy]

It was the 25 A one marked ENGINE CONT. I've replaced it though but it didn't make any differance.

Don't know if this is anything to do with the problem or not :roll:

Check your new fuse is OK. This fuse comes before the ECCS relay, so if it isn't working I doubt the ECCS will be getting power.

 

[zia]

there should be ecu relay somewhere have you checked that?

zia

 

[GINGA]

the ecu relay is beside the ecu on the passenger side
The engine should still run even with the maf disconnected, its a safety thing so you can still drive the car if the maf fails though it will only rev to 2500rpm and the engine light will be on perminantly.

 

[daz]

funny u should mention it i have exactly the same problem mine cut out last night travelling down the a38 would not go again,
changed the coil for a new one still the same mate next door has same car, so tried the ignition module no joy tried the dizzy on his car its fine produces a spark. put it back on mine the injectors fire but no spark :shock: :shock: :shock: got car checked out and towed to auto electrician as the coil was not sparking either. aa bloke says its either the wiring between ecu and coil or the ecu itself :shock: :shock: £££££££

 

[MarkTurbo]

Cheers Lads

Problem is sorted now, it was the ecu relay :roll: Only £19 to fix

I was starting to have visions of a dodgy loom or blown ecu and ££££££££££££££££££££

funny u should mention it i have exactly the same problem mine cut out last night travelling down the a38 would not go again,
changed the coil for a new one still the same mate next door has same car, so tried the ignition module no joy tried the dizzy on his car its fine produces a spark. put it back on mine the injectors fire but no spark :shock: :shock: :shock: got car checked out and towed to auto electrician as the coil was not sparking either. aa bloke says its either the wiring between ecu and coil or the ecu itself :shock: :shock: £££££££

Thats exactly what my car was doing (or not doing :evil: ) :?

Look next to the ecu, theres a little green relay that comes off the loom near the ecu wiring plug. Lever the plastic casing apart and make sure the contact inside moves across when its energised (ignition switched on)

 

[daz]

mark were your injectors working but just no spark ??

 

[daz]

found out wat my problem was . it was a wire that had rubbed on the chassis. this meant that the injectors were putting loads to much fuel in hence the car has bore washed and quite alot of fuel in the oil problem solved now just gotta keep eye on it and change oil a few times to clear it out :shock:

 

[Fast Guy]

Which wire was it? Incase anyone has the same fault.