Technical stilo with big problems help needed

[richydraper]

you never know bud there might be someone local who could help you out with FES all you have to do is ask if you need anything!!

might help you out before you can get your grubby little mits on a lead!

 

[mad max 2]

right tried lambda sensor pre cat 12 volt going in on both white wires doesn't appear to have anything on the signal wire the post cat same 12 volt on both white wires signal wire black just registers 8 ? however changed map sensor for my old one put my old plugs back in put 15 pounds worth of fuel in did approximately 48 mile. on the other hand reved the car up lost the throttle totally ticked over but no throttle. did a throttle sync came back but then went again. diconnected battery for half an hour connected back up performed throttle sync again works but ticks at 2000 rpm and takes it time coming down form 5000 rpm -very slow. whilst driving temp gauge shot straight over to red warning lights came on saying stop then went back to normal. it did this 2 or times, but now alright apart from throttle still sticking very sluggish 2nd gear and struggling to go up hill. i think maybe both lambda's are nacked any suggestions?

 

[Deckchair5]

tried lambda sensor pre cat 12 volt going in on both white wires doesn't appear to have anything on the signal wire the post cat same 12 volt on both white wires signal wire black just registers 8 ?
Something wrong there. If you have 12v registering on both heater wires then no power is going through. One should be 12v and the other should show close to earth 0v so it sounds like an open circuit there. WIth ign off and lambda disconnected, check resistance through the two white wires, should be low resistance thru the heater element. No circuit would be bad news

I'd check the ECU earth C40 as the ECU is not supplying earth to lambda heaters, they don't heat up and lambdas won't work very well or at all.


Do a voltage drop test with engine running from the tag on the ECU earth (bottom left mount screw in red circle) to battery earth. Should be near 0v
It looks from your figures like you haven't got a good ECU earth at all.


Also check the main battery to engine earth as this will give the same symptoms and problems. Simply touch the ECU body with one of your multimeter leads and check volts between there and battery earth as shown above

signal wire black just registers 8 ?
8 what? volts? That would be pretty spectacular. Should be showing 0.15v to 0.85v compared to earth when they are working but they don't start to work until they get hot enough and for that the heaters would help if they were working. That also looks like no earth at ECU

 

[mad max 2]

HI decks tried cleaning earths even the one under battery housing still same.When testing lambda no signal? So went to garage thay put the car on a dinostics,wait for it! banks 1&2 no o2 readings,cam sonsor,air temp minus30?map sensor,Do u think possable to do with wires from map burning on exauhst blowing the ecu.just been out and got a rope with a noos on the end !! cheers Rob

 

[Deckchair5]

It's very likely that the loom melting is the root of your problems. It would have to be MAP, air inlet temp and lambdas to be causing such dire fuel consumption. Diagnostics should be firing fault codes all over

You said you replaced the damaged loom though so why is the replaced loom causing problems?

Make up your own earth wire for ECU earth C40 and run it directly to battery earth and see if you get life out of the lambdas. If they have lambda heaters working ( you have 12v there so it's just a question of getting earth there too) then the lambdas should spring into life and you may find your MAP and air inlet temp sensor and cam sensor all working too as they all rely on ECU earth C40

 

[mad max 2]

Thanks for the reply decks.So its not the end of the road yet . I will give that ago tomorrow. HO when i tested o2 sensors i picked the earth up on the grey wire was that right?. Or have i mucked it up? just a thougt. thanks

 

[Deckchair5]

2 white wires are lambda heater
one should have 12v and the other earth- doesn't matter which way around
grey =lambda earth
black = lambda signal but it will only work when it gets to quite high temps

 

[mad max 2]

Hi decks. Both white wires have got 12v? ive tested them when hot must be getting earth as i used grey wire on multi plug? Fit new lambda on pre cat still no signal.

 

[Deckchair5]

I'm not sure what your measuring from and to where so grab yourself a pin and with everything engine wise all connected up and the black lead of your multimeter on the battery neg tell me what voltage you get when inserting pin into the back of the pre cat lambda connector with ign on for each of these wires, one at a time

white 1
white 2

and with engine running and warmed up
black
grey


Don't go buying new parts until you've sorted out the circuits. If there's no circuit then none of it will be working properly

 

[mad max 2]

Hi there just going out to garage to try again, but am sure those reading were correct,Had to use weding torch to get old lambda out!!

 

[mad max 2]

Just tried again back pinned both white wires 14.35 on one and 14.40 on other letting it warm up ive tried black before even with fan running thats hot! cant seem to get a signal taken readings with neg to battery all readings on dc and with earth from ecu to neg post on battery

 

[mad max 2]

Ok 1st with ing on 1st white 0.02. Sec white 0.02. Grey 0. Engine running. both white wires 14.35v on dc. Grey 0. Black 0.1 up and down to 0.03 on 200m set on multimeter? Sorry to be a pain!!

 

[Deckchair5]

Ok your black signal wire should be producing an oscillating voltage on tickover from around 0.2v to 0.8v around every sec like this

I'll see if I can get some baseline voltage figures for you tomorrow so you can compare

 

[mad max 2]

OK decks. thank you. stuck pin in finger as well just for good mesure, have tride to do what you said, but am i going wrong any where? do you think i should scrap it....Thanks for all your help so far.

 

[Deckchair5]

stuck pin in finger as well just for good measure
Ha! Well it keeps you awake

Ok well as expected here are baseline figures for my 1.6
with engine running
heater wires
white (nearest edge of connector) 14v
white 2nd one in 0v
grey 0v
black oscillating 0.3v to 0.8v

So you have an issue with your connections/wiring from ECU and what looks like no earth being supplied and that's why your lambdas won't work and many of your other sensors like MAP, AIT and cam sensor


I would check the ECU earth point C40, make sure there's no wire breaks, trace the earth wiring up to the ECU and make sure C40 connector is working properly

am i going wrong any where?
No, maybe switch your multimeter to 20v so you dont get confused

do you think i should scrap it
Hell no. Sort it

 

[mad max 2]

Thanks for the wiring diagram. is it possible for the earth to be broken in side the ecu?. Ill tell you why i spoke to the guy i got the car from today And he said the car droped a belt and he had it repasired !He got it back but was noisy but run ok.Till the wire bunt on the exsuhst and after that it run like a bag of s***I got the car took the head off and found it had 8 broken valve guides cut a long story short i put new engine in and all new wiring from engine to ecu and fuse box only thing i used from old engine was the ecu . sorry about essay but thoughtit might help point a finger at the problem any way got some croc clips from mapplins and if you think its a broken wire ill strip casings off and have a go .

 

[Deckchair5]

Well there could be a lost earth inside the ECU but are you sure you have ECU earth C40 connected? It should be on the lower left mounting bolt of the ECU. Without it the ECU has no proper earth and it will find earth wherever it can through the next line of least resistance

 

[mad max 2]

Hi deck i wired ecu direct to neg post on battery incoparating c40 still no change?It seems a bit strange that this problem was there before and still there after wiring change. Can you tell me what pinn is earth on conector and also eart pinn on ecu.

 

[Deckchair5]

From the wiring diagram up above ECU earth is on connector B pins 5 and 6 and 21 and 22

 

[mad max 2]

Thanks decks.Like you say dont change any thing till you check wiring am going to strip wires back just in case fingers crossed.If no joy would it be possable to have ecu checked out any where?