Thinking Of Calling Out An Auto Electrician

[PsychoSimon 0]

as some of you know iv been having problems with my Mi since i burned an earth wire for the ecu on the back of the alternator (melted it between the alternator and the fuel rail.

 

since then its been getting harder to start, misfiring and carries on running (pre-ignitioning) when i turn it off. I've replaced the coil and ignition amp, and also checked the whole loom aroundthe burnt area for anything connecting to each other, heatshrinked every wire that was even discoloured and still no avail.

do you think that an auto electrician will be abe to help me?

 

Anybody know any good ones in telford area?

 

Regards,

Simon

[Rippthrough 98]

Not damaged one of your spark plugs in the process have you? If the heat conductor got damaged maybe one of the plugs is running too hot?

[j_turnell 137 3 Cars]

You tried a different Crank sensor?

[PsychoSimon 0]

i havent tried either in all fairness. i need to speak to my mate very nicely as he is taking his off the road for a winter overhaul see if i can borrow some parts will get new plugs and leads etc tomorrow, but i wouldnt have thought it could be these as they havent been disturbed in 1000 miles? (thats when they were changed)

also would the crank sensor cause the pre-ignition?

 

Cheers guys,

Simon

[Rippthrough 98]

Well if you managed to melt the rest of the wiring it 'may' be a possibility that you have damaged a plug too, you may as well check them over just in case.

 

Chances are you'll call him out and he'll go , ".....ermm."

[PsychoSimon 0]

yeah will check them tomorrow definately.

i'm hoping that i can find it soon as it's really getting to me. I have been told of a good auto electrician comany on an indutrial estate not far from me so will go and have a talk with them and see what they say. thing is i want to establish that i only need them to diagnose the problem lol. i'll fix it myself to keep the costs down

 

will let you know how i get on with changing the plugs,

Regards,

Simon

[Rippthrough 98]

yeah will check them tomorrow definately.

i'm hoping that i can find it soon as it's really getting to me. I have been told of a good auto electrician comany on an indutrial estate not far from me so will go and have a talk with them and see what they say. thing is i want to establish that i only need them to diagnose the problem lol. i'll fix it myself to keep the costs down

 

will let you know how i get on with changing the plugs,

Regards,

Simon

 

 

Is it always on the same cylinder/cylinders?

[Miles 331 1 Cars]

You might have damaged the ECU is you back fed the Earth wire,

I doubt any Electrician would look at it due to the conversion, I know a few people have tried calling them out before with no avail

[PsychoSimon 0]

in regards to the question by ripthrough, its on all four cylinders. literally feels as though its dying then kicking back in again about 1/2 a second later. it doesnt even seem to have any time for it hapening, i.e warm etc.

If i had damaged the ecu would it mean it could pre-ignition even though i have killedthe power? although thinking about it they do have a fixed live don't they?

i was trying it by just disconnecting the battery last night and it didnt do it once, but this may just be that it wouldnt have pre ignitioned anyway at that time.

 

changed the plugs leads rotor arm and dizzy cap today and still no change. misfired 7 times in about 60 miles tonight, then pre ignition at the end of it.

I might see if batoutofhell will lend me his ecu for a couple of days.

 

how much am i looking at for a new ecu and possibly loom as well? the trouble is i hardly ever see any advertised....

[hman205 1]

is it over fueling? had a similar problem recently the ecu coolant sensor had a bad conection causing misfire and overrun

[PsychoSimon 0]

i had noticed actually that there has been a slight popping from the exhaust, and it hasnt been doing as well on the fuel. this i will try tomorrow, so thinking about it yes i think it is.

Tried a different ecu tonight and still no change, and i know the ecu is good.

Is there any way to check the ecu temp sensor? resistance etc?

the only things left now to change are ecu temp sensor, crank position sensor and wiring loom.

Anybody know prices for these sensors?

[OlberJ 1]

Same thing happened to mine before i realised the loom was rubbing on the gearbox and shorting out (bare wire on metal), caused a massive jerk when accelerating.

 

Check the actual loom and see it's not rubbing just at the brown multiplug where the gearbox and engine join.

 

Am tryin to price up a new loom myself but no joy, let me know if you find out please.

 

 

Cheers,

[PsychoSimon 0]

i've sorted it now, have basically re-made the loom. cost me about 150 quid in total i think, pm me if you want me to makeyou one i'm sure we could come to some agreement but basically all i did was use a multimeter and a soldering iron lol. and lots of plugs. you would be surprised how many connections there are in the looms!!

just copy the existing loom. Maplins would sort you out with the parts

Regards,

Simon

[OlberJ 1]

Hmmm, seeing as it's just sitting on the drive at the moment i may just take it out and replicate it.

 

Was it fairly straight forward?

 

If you fancy writing up a wee guide am sure it'd be most usefull for me and the site aswell.

 

Did you keep the brown multiplug or bypass it/make it straight thru?