telf

Hi all,

1st post on the forum but I've been a lurker for a while!

As per the title it's an ST170 on a 54 plate with around 60k on clock.

Problem is a bit hard to describe but I'll give it a shot.

If you drive the car very quietly (gear change approx 2k) all seems not to bad just a bit jerky but if you press on the accelerator a bit harder the car just dies basically and you need to coast to a stop. You can't rev it as pressing the pedal has no effect what so ever. You need to let the car sit for 10-15mins before it even considers restarting then it will idle but not rev until it feels like it and you can set off again but slowly until it decides to cut out again.....so repeat the above! this is fairly annoying so its parked up!

I have taken the imrc box off and change the tp121 transistor and put it back together (the were no fault codes relating to this but an auto electrician said it wasn't working correctly and causing the issue) the imrc works fine, when started it moves to the closed position and when about 5.5k and above it opens. I have also tried running the car with this disconnected and it made no difference.

The battery light seems to be coming when higher up the rev range then will stay on for a bit a low revs and the dash lights dim and brighten as they please. the voltage across the battery is approx 14V when idling but I haven't checked its output when up the rev range yet.

Any ideas guys?!

Any specialist garages about or recommended ones?

Anything else to check?

The car is standard apart from a k&n panel filter which has been on the car for 2 years.

Cheers
David

telf

Anyone got any ideas?!

telf

Still hopeful that someone can help!

phil_focus

TPS perhaps as the throttle appears to be not working?

The dash lights is a common problem, just don't set them on fully bright and they wont flicker.

deano2690

do any fault codes show up? do a diagnostic on the dash and see if any codes show up.

telf

When the car is not under load it revs fine. Tried that tonight.

There are 2 existing fault codes relating to the lambda sensor but they've been there for a year or so!

I have a code reader if that's what you mean?

H3lsing

I was going to suggest the imrc but you've mentioned it. That's the big one with that particular st. It sounds like from reading your post that she's in limp mode. I would bring it to ford and have one of their tech's scan using the ford IDS scanner. It is the only type that will be able to read them properly apparantly.

One thing you could try is to disconnect the battery for 20 - 30 minutes and maybe it will reset itself. It can happen . Any warning lights on the dash? Did you let her run low on fuel recently?

telf

Think I'll just bit the bullet and get a new imrc box best case it fixes the car, worst case I sell it and loose 50 quid!

If the new imrc doesn't solve the issue I think I have no choice left but to give it into Ford for a look; which I imagine wont be a cheap experience

Fuel is always above the quarter - not a believer on letting it below that unless absolutely necessary.

Only warning light is the battery on occasionally and the engine management but that's due to the lambda sensor fault which has been there for a year or so. Have tried to fix it but that's a separate issue for now!

telf

Bought and fitted a brand new shiny imrc unit tonight.

car seems a bit better so its one thing def off the list.

now the problem is the battery light.

start the car and all is well for about a minute then something kicks in and the cars tone noticeably alters and the battery light comes on.

multimeter across the battery and it reads 13.8V before and after the battery light comes on.

took the car a run and it pulls fine until the battery light comes on then it wont rev and just dies away. sit for 2 mins and start it and all is well again until the battery light appears.

I have no idea what is causing this, any ideas?

it isn't the fans as they eventually come on one its at temp.

hopefully once this is solved it will be back to normal!

telf

Morning lift to the top

telf

Almost back to normal now, found a broken wire coming off the alternator.

Soldered it and the battery light is off and car going fairly well. With the battery light on the alternator wasn't fully charging the battery and causing all sorts of issues.

Now I have a new issue though.

I think the fuel pump isnt exactly working as it should do

Has anyone put an up rated fuel pump in or found a cheaper alternative to fords rip off unit?

telf

anyone?!

H3lsing

How do you mean the fuel pump isn't working as it should? does she cut out?

telf

Sitting at between 2-3k rpm you get a sort of judder feeling and then when you plant your foot you get the same but more harsh.

It's like you are on and off throttle and the car sort of bounces down the road if that makes sense.

Doesn't do it all the time either.

Sort of assuming its lack of fuel causing the issue.

whitenoise

Try changing the fuel filter first, its underneath near the tank. Maybe blocked up.

H3lsing

Can you be sure that it's a fueling issue? sounds like, from you're description that it's misfiring to me.

telf

Fuel filter was changed about 3 months ago so hopefully its still all clear.

Nope, I am not 100% sure that it is a fueling issue.

The car seems to idle ok which is why I hadn't considered a misfire.

Would it not pop and bang because of the extra fuel in the cylinders?

Drove it to work this morning and it seemed ok until near the end of the journey (previous to this i had been driving like miss daisy). I planted my foot (out of curiosity really) coming off a roundabout and it just kangaroo'd along the road

foci

Was it doing it before the fuel filter change? If not I would check the flow direction in the filter. Just a thought

CoupeUK

My old 52 ST170 did this, I also had the EML light on...changed the lambda sensors and all was well.

telf

Yes was doing it before filter change. This was the reason for changing it. Will double check the arrow to be sure though.

Going to test the lambda this week at some point.

Anyone got details on how to test them? Or autodata to find out?

I have ruled the lambdas out though as the fault code for them has been present for a year or so!

telf

or does anyone know the fuel pump part number?!

phil_focus

Were the lambda sensors ever replaced?

the st170 can crack the fuel pump housing which lets air into the fuel lines. Worth checking for.

deano2690

mine did this, turned out that the plug wells were full of water
Worth checking at least.

What about the plugs, coil pack, plug leads?

telf

Already replaced the lambda sensor but have another one that I got today.

Also got a second hand fuel pump.

Both getting fitted tomorrow and hopefully that's the end of it all!

Would there not be a code regarding spark etc?

Don't see it being water as the car goes. The fault is intermittent.

Yesterday it died on me. When it revved it was really struggling but after a 10 min break it cleared itself.

These 2 new bits better fix it!

telf

fuel pump and sender unit fitted and its going a treat.

replaced lambda sensor 1 and thats got rid of the code for that.

lambda sensor 2 is ordered and will be fitted during the week and that will get the EML off altogether

both sensors had the heating element failed, this usual?!

then all thats left to do is change the porous sump and it will be perfect.

oh and up for sale lol

phil_focus

all usual problems to be honest as they like eating lambda sensors, cracking fuel pumps and sumps rot once chipped (had to do mine on my 2l zetec, not easy getting the old one off as its bonded on).

Don't forget to clear the fault codes once all the new bits are fitted. You can do that with your fault code reader.

If all is well then it should be good for a long while so I wouldn't feel in a rush to sell if I was you.