Delta-Force

Hi all ive bought a focus st170 recentley that has a few of the usual faults the last owner had removed the bulb out of the eml

on the way home i noticed its mega heavy on fuel im talking from light on £10 of fuel 38 mile later and its back on thats driveing with gear changes at 3k so i pluged it into my reader and it came up with these faults the P1518 IMRC stcuk open so i checked the clip its not broke so i removed the imrc unit and took it apart to check the contacts inside with a multi meter and thats working ok i then checked the motor on a power supply and thats working so ive orderd a tip121 transistor so see if that will fix it so il have to wait for the part to come before i carry on with that now and hope it fixes it as ford stealers want £190 for a new unit

but the other problem P0135 and P0141 seems to be saying that bank 1 sensor 1 and bank 2 sensor 2 lambda sensors have failed what are the chances of them both failing at the same time i thought this was a bit weard can anyone shead any light or have you come across it before ?

anyone have any ideas or have you got a st and had the same fault just thought id add a post to see if any other fellow st owners have had these problems before any help or info would be great though cheers mark



btw i have checked the fuses and checked the wireing for burns splits etc and it looks fine




Diagnostic Trouble Code (DTC) P0135
Front Heated Oxygen Sensor Heater Circuit Not Functioning

This code means that the heated circuit in the oxygen sensor on bank 1 decreases time needed to enter closed loop. As the O2 heater reaches operating temperature, the oxygen sensor responds by switching according to oxygen content of the exhaust surrounding it. The ECM tracks how long it takes for the oxygen sensor to begin switching. It the ECM determines (based on coolant temp) that too much time elapsed before the oxygen sensor began operating properly, it will set P0141.

P0141

O2 Sensor
Heater Circuit Malfunction (Bank 1, Sensor 2)
This code means that the heated circuit in the oxygen sensor on bank 1 decreases time needed to enter closed loop. As the O2 heater reaches operating temperature, the oxygen sensor responds by switching according to oxygen content of the exhaust surrounding it. The ECM tracks how long it takes for the oxygen sensor to begin switching. It the ECM determines (based on coolant temp) that too much time elapsed before the oxygen sensor began operating properly, it will set P0141. See also: P0135 (Bank 1, Sensor 1).



P1518.
Inlet runner control stuck open

intake manifold air control solenoid, bank 1 solenoid stuck open

oldford

2 Heaters failing at the same time is usually a fuse or a relay. As far as I know Ford does not look at the sensor signal for setting these codes.

Delta-Force

ahh i didnt think of checking the relay i will have a look into that pal dont suppose you know witch relay it is do you for the lambdas ? cheers mark

Delta-Force

Well a bit of a update i replaced the transistor with the Tip121 off ebay they was £0.99p buy it now for two of them .

ive bin into electronics and soldering since i was around 14 so it helps being a dab hand with a soldering iron but theres a good step by step below i

Followed this link

http://mrhightower.googlepages.com/imrcfix

any bingo it works a treat cleared p1518 fault cars got loads more bottom end and i did 50 miles of mixed driveing tonight booted it a few times here and there and only realised id forgot to put the cold air tube back into the bottom of the airbox when id had the airbox off sounded good though but prob made it get a little less mpg mind you ive put it back now still sounds nice with it in and seems to pull a tiny bit better
saved myself £191.51 if you include the 99p the transistors cost me lol



result .




only 2 faults left now P0135 and P0141
both lambda sensor faults will get my head into this asap now had a quick look at the wireing but not tested anything yet due to poor weather thought id update this as it may help others one day

pdfbt40

ST170 have a reputatation for eating lambda sensors. Both your codes relate to Bank 1, which isn't surprising as it isn't a multi bank (ie V) engine.

The heaters are switched directly by the PCM IIRC, no relay, and are only turned on for a faster warm-up. Once a good signal is being received they are turned off. So the fault does not affect the normal fuel/air control at all.

As you intend, check the wiring and resistance of the heaters (the 2 white wires at the sensor). Also use a switch cleaner on the connectors. Although sealed the contacts do still oxidise.

Martin

Delta-Force

hi martin thanks for that it makes sense really as ive read above P0135 will set P0141 and thought about that before .

id be best buying them one at a time really . Ive checked the fuses had a good luck at the wireing to check for melting on exhaust etc unpluged both sensors checked conections everything looks fine so far .

any idea if i should have any voltage on the white wires or is the plug only in use on cold startup ?

pdfbt40

The White wires are fed from F18 (10amp). At the connector (Pin1) the wire is GN/YE (front) or GN/BU (rear). The other side of the heater (Pin2) the return wire to the PCM/ECU is BK/YE or BK/BU. Ford state the heater resistance is 7-15ohms.

One can never be sure, but I believe its just a power transistor to ground (monitored for DTC) during warm up of the exhaust/sensor. Once it get sees a sensible signal from the sensor (switching ~0.15v or ~0.85v) on the black and grey wires, the heater current is switched off.

In fact if the DTC is cleared at this point, it doesn't come back until the next cold (sensor) start.

I use to look inside the connectors and think they were clean, but a couple of times (and others have found this) a squirt of switch cleaner/lubricant (WD40 if real stuff not around) and the fault clears.

Martin

zvhturbo29rs

iTrader: (7)

it will be both sensors mate,worked for ford for 5 years as tech.common problem

Delta-Force

Thats great thanks i will re check all the wireing again and the resistance on the heator i think asap just to make sure . i dont mind buying the parts if it needs them im just trying to make sure its 100% faulty then i can buy them without worrying or being gutted because it wasnt that

zch they may well be both faulty pal but eather way i think the best thing to do would be test all wireing and do a resistance check on the heator as it costs nothing anyway then replace the front sensor then the rear after if ive still got a fault i just dont want to spend £100+ buying them and its not that as you can imagine .. theres nothing worse than doing that buying parts you dont need ive done it enough times lol

Delta-Force

well looks like you were right pal

P0135 was the front lambda P0141 was the rear lambda and P1518 was the imrc not working bought

NGK 0ZA488-D2 (Front Lambda) £50.60 inc vat Cleared P0158

NGK 0ZA381-D3 (Rear Lambda) £50.60 inc vat Cleared P0141

And TIP121 Transistor Fixed My IMRC Problem £0.99 off ebay

job sorted at long last no more eml

alpacino266

hi mate, where is the tip121 located, also could you tel me where the lambda sensors are located both of them...please

also when i drive my ford focus st170 its starts jerking doesnt have speed left as in: when i give it some at 4000rpm it starts to sort of loose power, keeps and sort of shaking.

also when my car warms up and when i drive the tempreture drops. can you please help me on this. please email me: bronx266@yahoo.co.uk

Delta-Force

hi pal really you want to buy a fault code reader off ebay something like a u480 will do unless you know someone who can scan it for you otherwise you could end up spending £££ on the car and it still not fix it ..

tip121 is a transistor thats inside the inlet manifold runner control box this some times burns out and can be fixed but thats if your lucky really a lot of the time the cable breaks and destroys the imrc box these are prone to going the make the car run very rough no power below 4000 rpm have a look at this link it shows you a how too change tip121

http://sites.google.com/site/mrhightower/imrcfix

but you will need some soldering skills to do it the box is bolted to the firewall just behind the engine check the cable is not broke first just follow it and have a look

in the link the guy it working on a st24 mondy i think but the imrc box is the same to repair so it still a good link ..

your lambda sensors are under the front of the car ontop of the cat you will need a 21mm ring spanner or a lambda socket to remove them if these have gone the car runs in a fail safe mode thats very ritch so between this & the imrc box not working your car will drink fuel bigtime and loose a lot of power

but like i said if your engine management (EML) light is lit get the codes read before you touch it its well worth it

good luck

cheers mark

alpacino266

Thanks Mark For the quick response respect. i will look into it, it does drink alot of fuel put in £10 gave me 17miles :wall. my EML light been on for quite a long tym now, also when i start up in morning takes ages for it to warm up. once i repair i own u if ur right!

alpacino266

btw mark where did you get your lambda sensors from?

Delta-Force

Hey sorry for the late reply man been mad busy recentley i got the lambdas from alan quine ltd its a small shop in bury

Alan Quine Ltd
253-255
Parr Lane
Unsworth
Bury
Tel - 0161 796 5797

the spanner is 22mm i bought a 22mm spanner and the 2x lambda sensors it cost me £106.89 all in inc vat there ntk lambdas too so there good quality and direct fit no cutting wires etc like the cheap ones you get

Trust me though man get a fault code reader like this

http://cgi.ebay.co.uk/UNIVERSAL-HAND...item45ee2ac075

ive got this and it works on most cars and its easy to use saves you paying £50+ to have them read at a stealers

when you have your codes eather read the book that comes with it or goto

http://www.obd-codes.com/

and type the code into the search for a better description of the fault its well worth knowing thats the fault for sure these codes i had i read off my own car so i new exactly where to start getting to work these are one of the main faults on st170's tbh but it does drive 100% better when its spot on i get around 50 to 55 miles to 10 litres of fuel now (about £10.70 ish i fill up by the ltr not the price as it changes so much from town to town) thats day to day driveing with traffic starting stoping etc dont get me wrong if i boot it some i get less but thats good really it was unreal how much it used with the imrc fault and both lambdas not working ive drove 2.8 and 3.2 petrol cars that used less fuel when it wasnt running right its pritty much doubled the miles i get bearing in mind my car is standard engine wise no mods like induction kit de cat etc

hope this helps

cheers mark

tuftysst170

hi fella did your eml light stay on all the time with you P1518 code?? Mine doens't comes on rufly every 6 weeks but allows me to erase error! And you seem to get more fuel consumption then me.

Delta-Force

hi im not sure as mine had other faults as well at the time but it could be the imrc on its way out as if it does go i think the light will stay lit . get your car warm look for the silver box thats bolted onto the bulkhead follow the cable that comes out of it you should see it connected onto the inlet manifold rev the car past 4000rpm and you should see the imrc open then close it could also be the cables snapped so worth a look pal .. as for the fuel i put fuel in by the litre so i get 10 litres most people dont so they put £10 in and get 8.75 litres etc so its less than £10 worth of fuel in theory lol i only do this as the price changes from garage to garage so much

cheers mark

tuftysst170

cheers fella.

Liberachi

Hi guys. What a relief reading this thread.

My IMRC unit is broken according to the garage and they said that they can replace it for me at a cost of £500 including labour.

Basically my car runs much slower than it used to and the power level does fluctuate when giving it full beans. The EML stays on. I've been encouraged to read that this might be repairable by my own means.

Is is just a case of trial by elimination? If I replace the tip121 and there is no change then can I buy and fit a new IMRC unit myself?

Thanks in advance.

Delta-Force

hi pal check the cable and gears inside the imrc are working smooth as if its jammed they self destruct themselfs then replace the tip121 there cheap off ebay its a 3 leg transistor inside the imrc as long as your ok with a soldering iron its very easy to fix this will only cost a couple of pounds so its worth a try and yes you can buy a used imrc and fit it yourself but how long a used one will last is a chance you will have to take but thats like any used parts really . i used the hightower link i posted above it helps you out if you have never done one before


hope this helps cheers mark

Liberachi

Thanks for the prompt reply mate. I went into my local Ford dealership the other day and they are quoting £320 for parts and labour. I'll have a wee look under the bonnet tommorow and see whats what. Thanks again.

snares

hey guys first post new to all this. just a quick one really, got the dred p0141 just wanted to know if this is before or after the cat?? err code says sensor 2 so assuming after??

thanks guys

Delta-Force

its Bank 1 Sensor 2 p0141 is the rear sensor mate see the post i made above

snares

thanks mate, much appriciated.

Bks

i have an ongoing issue with my st170 with code 1518 told to replace the irmc unit, been hearing alot about this tip121 transistor replacement, where do i locate this transistor

pdfbt40

Delta-Force has given it all above.

If you mean in the IMRC
http://mrhightower.googlepages.com/imrcfix

If you mean to buy, search Ebay
http://cgi.ebay.co.uk/2-off-TIP121-D...item3a5a2596ff

Martin

Bks

the cable and bracket will only move once in a life time when i use a brute rev force on the throttle

Bks

also i have had to keep tightening up my throttle cable to keep it running well, is this cause the IRMC unit is not working or is it cause my inlet manifold is not working correctly help

Manni_V

Thanks for all the info and advice guys i needed this help as well!

I bought the ST170 a few days ago with engine light on and had these codes appear when it was diagnosed
I have bought the bosch lambda sensors rear and front from ebay and also the IMRC unit from fordparts.com
only drawback is i cant get them fitted until after a week

i wont have a problem in driving around like a granny until then will i apart from the petrol being pi**ed out constantly by the car lol??

alpacino266

Hi Delta..

ive got a EML light on again. its bringing up code DTC: P1581????

Dont Know What That Is Can YOU HELP?? searched google for it seems nothings coming up.

Cheers

phil_focus

Hi, my library brings this up for that code

"Electronic Throttle Monitor Error"

not sure if thats right tbh as the st170 isn't fly by wire throttle so i'm a bit confused unless it relates to the tps but i would have thought it would say something like "tps fault"

sorry i cant be more help

pdfbt40

Sure you've not miss transcribed it P1518 is the common IMRC failure code.

alpacino266

Where Is Your Library?????

phil_focus

on my laptop, came with my dirt cheap code reader so i don't think i has all the codes but cirtainly most.