immobiliser - makeshift

[Aragorn]

ok while im getting round to fitting killswitches (need to buy the switches) i have started uni

and im parkin the car in this dodgy train station car park (well round the corner cos the car park was full) so there is no cameras or shite

so i decided to see if there was an easier way to stop oppertunists trying to nick it

i poped the fuse box and noticed a fuse for FI - i assumed fuel injection so i pull it out

i then try to start her

crank, chug,chug, splutter,splutter splutter

so i think gid stuff and turn off put fuse in me pocket and go to uni

now when i get back and put the fuse in again - i crank the engine

starts fine idles for a second the revs rise to about 2000rpm - i blip throttle it goes up to 3500rpm then falls back to 2000rpm
then VERY slowly goes back to 900
so i drive home and think it feels gruntier sounds gruntier too

so what i want to know - was the high revs due to it spluttering when i tested it, or what i think - that the ECU has reset and went into a failsafe mode to start the car then adjusted itself once it was running

if this is true - is it safe to do this every day? or will it start to bugger summat?

thanks

[locky]

Not 2 sure bout the failsafe mode bit sorry m8, but on a cold day on my mums corsa, the autochoke comes in at 2oorpm, hit the throttle, and also goes up 2 bout 3000rpm, hit the throttle again and it'll go down,
Was ur engine very cold so that it needed more than usual possibly!
(btw, i dont know alot bout autochokes or fuel injection electronics, just a wild guess!)
Hope this helps!

[mikeoxford]

the "FI" fuse you took out is quite rightly "fuel injection" all it powers though is the fuel pump.

removing it is a good idea, but all a thief has to do (if he works it out) is nick any other random fuse from the fusebox, and push it in! fuel pump dosent take much if any current.

good idea though - will stop the thief in his tracks a good few extra mins

as for the splutter,

you have cranked your engine without the fuse, meaning no power to the fuel pump, therfore you have starved your engine of fuel, the turning over of it again and the spluttering is as the petrol is getting back through.

probably runs at a higher RPM because it is struggling at first. (lack of fuel)

[Ben (lurk75)]

Yes as Mike said, so if you dont start it before inserting the fuse back in then it will start fine when you do.

I doubt very much if a oppurtunist thief would even think of checking what fuse's are missing and is more likely to think you have an immobiliser and give up and nick the next car- NOT your problem :wink:

Good idea :!:

(or unplug your ECU everytime you park there :!: )

[?Marty?]

take the fuse for the lights out too.

[GR]

Another good way is to take out the main dizzy coil and keeping it on you. Try startin a car with that missing !! :twisted:

[Anonymous]

take the octane plug with you, bit harder to find lieing around than a fuse!

Chip

[Ric 16v]

it's ok saying take the fuses out but haven't u forgot 1 thing, the thiefs can still nick everything out of it or even burn it 2 a sinder, think about it !!!!!

[Ben (lurk75)]

LOL bag will be full of car parts rather than books :!:

As SRi16v said they can still break in and nick everything but dont be fooled that having an alarm stops this, as who really pays attention to them anyway :?: Not many :!: So even having a decent alarm dosent stop anyone breaking in :!:

[Manta Mad]

Interesting to read about the ECU resetting theory. I had the battery disconnected in my Nova for a few days, when I reconnected and started the engine, it didn't run well for a few miles then all was OK again - would cutting the power make the ECU resett? - This is happened a couple of times.

[Chris LR]

I don't know much about alarms which is why I asked my mate if he knew where to get a decent one from, he went away and about 3 weeks later he produced a little black box, a couple of internal sensors and a speaker, he had my car for an afternoon and fited the alarm/immobiliser himself.

I know what your thinking, nothing special there, but when the alarm goes off it hurts your ears. it's so loud and painful I physicaly can't go within 15ft of the car.

I asked him where he got it from, he wouldn't tell me.
I'm sure there must be other tyres similar to mine about, though iI'm sure i shouldn't have it.

[mowgli]

just remove the fuel pump relay......

Once, a gang of tow rags spent a fortnight trying to nick my nova, cos the prat from the local MOT station told them what it was, and how fast it went on a road test. They had tried the old 'We heard from a bloke in the pub that it was for sale, and could we have a road test' routine. They popped the door lock out but all attempts to start it failed. When I fixed it, and re-fitted the relay it ran perfectly. I have never had trouble with the failsafe cutting in..

[Aragorn]

ok all the fuse does is power the pump

so the ecu was not reset

disconnecting the battery will clear the ecu and all its stored settings about fuel mix and stuff - it will take a few miles to get everything back the way it should be

what i think happened is this - ive tried to start it with no fuse, ecu notices its running lean (it did run for a few secs) and adjusts the fuel mix and timing to compensate, then i turn it off so it saves those settings

then once i re added the fuse and started it it would be using the adjusted mix and timing settings hence the high rpm's after about a min it readjusted itself

[Dicko]

that fuse on the GTE is for the whole injection system, including the ECU, fuel pump relay etc

basically id take the fuse and thats that. If it was a pro he wouldnt be nicking a nova. Joyriders are kids who know nothing, they would never look in the fusebox.

And the GTE doesnt have a RON plug btw

[Anonymous]

sorry, was thinking of the vavler lumps i guess, as i always whip the octane plug out on my nova.

A switch hidden in the boot for the fuel pump is a good idea too.

Chip