Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: steven2880 on 27 May 2008, 08:59:35

Title: injector immediately open when ignition on
Post by: steven2880 on 27 May 2008, 08:59:35
Hi there ,have been trying to sort out a sick 1996 omega estate 2.5 v6 which seemed to have all the symptoms of plug/leads/dis missfire .have checked though and found that as soon as the ignition is switched on one of the injectors is immediately open and allowing fuel through at an alarming rate . this seems to account for the poor running missfire and huge amounts of smoke/fuel in exhaust. Has anyone else encountered this before ? also as my mechanic friend feels that the problem seems internal to the ecu if I can source one to fit my car will I need additional parts like the key chip / transponder for immobiliser in order for the car to be started after ecu change ?
Did think that there was a wiring issue like the injector wiring was earthing on the one at fault but think he has checked the wiring continuity and this seems fine hence the belief that its an ecu issue that we are looking at .
Can anyone help please ?
Cheers guys Steve
Title: Re: injector immediately open when ignition on
Post by: markey mark on 27 May 2008, 09:59:52
yes you need key chip and transponder from ing lock  :y
Title: Re: injector immediately open when ignition on
Post by: Kevin Wood on 27 May 2008, 10:17:00
It's worth checking for a wiring problem. Injectors are fed from a +12v supply from the main relay in the box near the battery. The negative side of the injector is switched by the ECU, so there's a possibility that injector's negative wire has been shorted to chassis somewhere between the injectors and ecu. Try a resistance measurement between the negative pin on the injector plug and ground. Compare that with a reading on one of the other injectors that's working normally. Then try again with the ECU unplugged.

I believe we did nave someone else with this issue a few months ago, and it turned out to be a faulty ECU.  :-/

If ECU is proven faulty, it might be worth investigating getting it repaired, as it's likely just an injector driver that has failed.

Kevin
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 27 May 2008, 15:53:53
Thank you folks have spoken with my chap he's done the tests on wiring as suggested and the wiring is fine hence your suggestion that the driver has failed seems to make perfect sense . Am looking for a correct second hand ecu currently as well as enquiring about repair to the existing ecu .
Thanks Steve
Title: Re: injector immediately open when ignition on
Post by: Entwood on 27 May 2008, 18:40:55
for repairs to ecu .. give these guys a ring ....

bba reman - 01634 230055 ... for the cost of a phone call you can get a whole load of info !!

I found them excellent on an ABS ECU .. :)
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 28 May 2008, 14:48:39
To all who have posted advice and suggestions thank you very much the wiring checks out and it would seem that an injector driver has failed in the ecu . I will try the phone number supplied for repair of the ecu but am somewhat fearfull of the cost involved . I have trade acounts at several local motor factors and the cost via their people was horrendous .
Did try to post a wanted but ran into the 250 posts problem which seems to affect a number of people when new to the site . I can follow the reasoning behind it though .
Dont suppose anyone has a bosch motronic 90457097  0261203270/271 transponder and chip they wish to sell.
If this breaks the rules I apologise bit desperate to get my car sorted
Cheers guys Steve
Title: Re: injector immediately open when ignition on
Post by: Entwood on 28 May 2008, 14:51:19
I can't say about engine ecu .. but abs ecu from VX was £600 + .. repair by bba reman was £130...

I know which I preffered !!!

:)
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 28 May 2008, 15:05:10
Just got off the phone from them helpfull guys but I'm going to be looking at £295 to repair which is a little steep compared to a secondhand part if I can find one .
As you said very helpfull though
Cheers Steve
Title: Re: injector immediately open when ignition on
Post by: Entwood on 28 May 2008, 15:11:40
If you change the ecu you have to have it re-programmed via a tech 2 I believe ... so factor that cost into your budget ...  the engine will not start otherwise ...

If I'm wrong an expert will pass by and correct me I'm sure ...  ;D ;D ;D
Title: Re: injector immediately open when ignition on
Post by: Kevin Wood on 28 May 2008, 16:04:38
Quote
If you change the ecu you have to have it re-programmed via a tech 2 I believe ... so factor that cost into your budget ...  the engine will not start otherwise ...

If I'm wrong an expert will pass by and correct me I'm sure ...  ;D ;D ;D

Correct - unless you change the immobiliser and transponders at the same time.

It's the sort of fault that's easily rectified, I reckon. Just change the injector drive chip.

Kevin
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 28 May 2008, 16:58:42
Thank you for that if I get offered a second hand one will try to ensure it comes with transponder and key chip . Otherwise a reprogramme via tech 2
Kevin you mention changing the injector drive chip is that something that can be done easily enough . It sounds like you have experience of this job and would a driver chip from a similar if not identical part number ecu do the job ?
Thanks guys sorry to be a pain do appreciate the help though
Cheers Steve  
Title: Re: injector immediately open when ignition on
Post by: doz on 28 May 2008, 18:05:59
Hang on a mo. If I was you i'd be changing the injector yours wouldn't be the first to fail open. I'm not overaly familar with the V6 but I know the straight 6 from early models batch fired the injectors. If you know which injector it is. Unplug it and fire the car up if it still pisses fuel then there's ya answer. otherwise I guess you've got a big bill to pay
Title: Re: injector immediately open when ignition on
Post by: Ian_D on 28 May 2008, 18:35:36
Quote
Hang on a mo. If I was you i'd be changing the injector yours wouldn't be the first to fail open. I'm not overaly familar with the V6 but I know the straight 6 from early models batch fired the injectors. If you know which injector it is. Unplug it and fire the car up if it still pisses fuel then there's ya answer. otherwise I guess you've got a big bill to pay

Yeh thats what I was thinking... Also if it does stop the fuel, at least the car can still be movable then (however, I wouldnt want to go very far!)

Im sure ive seen ECU + Keys go cheap on ebay loads of times.
Title: Re: injector immediately open when ignition on
Post by: Kevin Wood on 28 May 2008, 18:37:14
You could always swap the injector to another cylinder and see if the fault moves with it. :y

I've never looked inside one of these ECUs. I was thinking that the remanufacturing place would be able to fix it pretty easily.  :-/

Kevin
Title: Re: injector immediately open when ignition on
Post by: Pete Elite on 28 May 2008, 19:08:02
Quote
Hi there ,have been trying to sort out a sick 1996 omega estate 2.5 v6 which seemed to have all the symptoms of plug/leads/dis missfire .have checked though and found that as soon as the ignition is switched on one of the injectors is immediately open and allowing fuel through at an alarming rate . this seems to account for the poor running missfire and huge amounts of smoke/fuel in exhaust. Has anyone else encountered this before ? also as my mechanic friend feels that the problem seems internal to the ecu if I can source one to fit my car will I need additional parts like the key chip / transponder for immobiliser in order for the car to be started after ecu change ?
Did think that there was a wiring issue like the injector wiring was earthing on the one at fault but think he has checked the wiring continuity and this seems fine hence the belief that its an ecu issue that we are looking at .
Can anyone help please ?
Cheers guys Steve


 Hi,
    I was thinking it's not a good idea to let unburnt petrol into the exhaust cat. as it can do serious damage :(.

  Hope this helps,
                        Pete.
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 20 June 2008, 10:37:56
Hi eveeryone just a short note to say thanks to all who suggested possible cures for this problem . It was traced to number 5 injector opening as soon as the ignition was turned on . An internal ecu fault with the injector driver . Now cured with 2nd hand ecu car runs superbly .
All the best thanks again Steve  :y
Title: Re: injector immediately open when ignition on
Post by: ians on 20 June 2008, 12:08:12
result :y  what was the damage in the end?
Title: Re: injector immediately open when ignition on
Post by: steven2880 on 20 June 2008, 13:27:38
Not too bad buddy £112 for the ecu including vat and carriage and £80 diagnostics/labour . Could have been much worse
Cheers Steve :y