Gem frst

hi my fiesta rs turbo has started running really rough it will start but then try conk out all the and when i try to drive it will kangaroo and hesitate unless you really rag it and will fly ive tried new fuel filter pump coil pack swapped all the sensors on the inlet from a spare i had diffrent injectors nothing ive done seems to change the way the engine is running its a daily so need to get it sorted any suggestions would be welcome as scratching heads now its std engine with t3 conversion also ive tried with 195 chip and biege injectors and just on std blues and no chip still same running issues

stewarthannah

spark plugs, injectors or coils

Gem frst

changed all 3 2 sets of injectors ive tried 2 coils and set new plugs

stewarthannah

Was gunna say try the sensors but you have...maybe check the fuel lines for any leaks, do you know what cylinders are misfiring?

rsmark86

iTrader: (3)

He never said it had a misfire?

Sounds like a vacuum pipe or boost pipe leak

stewarthannah

Sounds like a misfire if it's konking out

rsmark86

iTrader: (3)

Read his post, says nothing about misfires

Even a retard could write it's got a misfire if it did, and he didn't, what he has said points too a vac leak, which will throw out the airflow and fueling causing the hesitation and kangaroo'ing

And will still "fly" on full throttle but he will melt it due too incorrect fueling

If it had a misfire it WOULD NOT "fly" when floored

SBT83

Had me in stitches reading this! Real tears^

rsmark86

iTrader: (3)

Oops did I write that lol

I'm pretty sure what I said should cure his problem, that and make sure fuel pressure is correct

Maxwell

I would check spark plugs and also have a look at the crank position sensor.

And mark to be honest if its "hesitating" it is actually misfiring as its being driven along!! But when "ragged" as he puts it - it clears!!

I would bet my fiesta, its the CPS. Dirt and/or moisture will effect the way it works!

rsmark86

iTrader: (3)

Your very right but a ignition misfire would not cause the "kangaroo'ing"

What your saying about the cps makes sense, if it's not getting a decent signal it would hesitate but if it was a signal problem I would have thought it wouldn't run, but I'm no expert so could be wrong

Also thinking about it I could be wrong and look abit of a cock lol, if it had bent valves on one or a couple of cyclinders it would miss, hesitate and cut out all the time but still pull at top end
As I have personally had this on one of mine when I over revved it

So I could be eating humble pie lol

SBT83

Need a spoon to go with the pie mark

Maxwell

I have never had a cps fail on on my fiesta rst.

But i have had it "cause problems" on x 2 of my saxo vts', as in one of them for example got wet as i drove through bad weather in france (started in Bordeaux and i had 7hrs driving ahead of me to Cherbourg) and as time went on, the car cut out and after a few times trying to start it, its started once out of 5-10 attempts and then you had to drive "spiritly" and it would hesitate. Luckily it cut out like 4kms from the ferry so i got towed by my mate!!! Also luckily, i had my tools in the back, i opened the bonnet at Cherbourg port and pulled out a suspect cps. It was covered in sludge - musta been dirty and got wet during the bad weather and turned to sludge. After a clean and a dry, i re-installed it and the car never ever missed a beat again in my ownership!!

The smallest issue can cause a big head ache!!

rsmark86

iTrader: (3)

So

Test compression
Cps
Vac pipes
Boost pipes
Plugs
Fuel pressure
12v at the fuel pump?

And a message too the OP

DOES IT HAVE A MISS FIRE ON TICK OVER?

If it does remove each lead 1 by 1 and see what one makes no difference when removed

And has it had any recent work carried out on it?
Could have upset something after?

Gem frst

Thanks for advice guys well no not noticed a misfire, it will start everytime just trys to cut out and when you blip throttle does settle and cut out done compression 134 all were 120 ish and 2 was 110 ish from memory tried new set of plugs and leads only work its had recently is a new sump gasket as had oil leak have checked the vac and boost pipes but will double check how would I know if its bent valve? Or is that what the compression test shows thanks for everyones help so far

costina

iTrader: (1)

Throttle position sensor......

Gem frst

Tried that allready

costina

iTrader: (1)

they are prone to failure

rsmark86

iTrader: (3)

If you have worked on vac pipes and boost pipes my theory is a good one

Make sure all the nipples on the inlet, two on top and two at the back are correctly connected or blocked off and too mapp sensor ect

And the boost pipes are tight

Gem frst

Not touched vac pipes or boost pipes when the problem 1st arised and double checked them there all fine since I been trying to sort the problem tried a known working cps and tps not made difference are the compression test results ok?

Maxwell

Check for dodgy earth cables. And failing that its probably a bent valve'n

rsmark86

iTrader: (3)

If it was a bent valve it would act like a misfire in tick over too

I'm with you on the dodgy earth

Something isn't right

What fuel pressure is it running, have you got a afr wideband, you said you have been changing chips and injectors

But each time you did this you should have been setting up the afr's and fueling too suit

This could cause it too cut out and hesitate

Gem frst

Ive only tried another set of std injectors and bieges and chip on a set rail to see if there was a problem with injectors but problem was there before

Gem frst

When I unplug map sensor it will idle fine bit obviously wont drive so would that point to map sensor?

arfurski

Im defo thinking a vacuum problem.

Gem frst

But where as there only to vac pipes on efi head one to map and one nothing or boost guage and both pipes are good changed them blocked them off to check to and still have problem but when map is unplugged will idle fine??

rsmark86

iTrader: (3)

Boost pipe
Vac pipe too servo
Vac too boost gauge
Bleed valve
Amal valve
Vac for mapp sensor
Fuel pressure vac take off ? (Aftermarket)
Boost pipes
Vac from charge pipe too idle control
Turbo air take off (where bleed valve would go)


Dump valve (very well documented that they fail) causing same problems you have

Also is it a ofac car converted too ofab (there's pin out changes needed for this)

Is it a mapp sensor too suit ecu you have?
And it isn't a cossie mapp sensor as this also requires a wiring pin out change too

Hence the unplugging the ecu sorting it ?

Gem frst

It was a running car Running fine for over a year so no pin changes or wrong map sensors as its happened while driving it not conversion done wrong its ofac from factory frst checked all boost pipes and vac pipes nothing wrong or leaking I can see or tell does not have dump valve just noticed when I unplug map sensor it seems to idle fine

rsmark86

iTrader: (3)

Try a new one

So does it have a rough idle? High idle speed?

Gem frst

Where can I get one do they sell them new and yes rough idle hunts alot ant trys to cut out all the time but with map sensor unplugged it seems to idle very smooth and normal

rsmark86

iTrader: (3)

Defo sounds like there's a massive air leak

Unplugging the map sensor causes the ecu to go into a safe mod, so hides the problem to some extent

Inlet not cracked or gasket leaking?

I say try another map sensor and do a vac/ boost pipe pressure test, you will need to pressure up the system too see if you can find leaks

SBT83

I was gonna say inlet gasket leaking. Could try the old carb cleaner trick on it for a cheap check?

Gem frst

i would agree but until the problem the inlet had not come off how do you carry out a pressure test it dosen't have a high idle which i thought a vac leak would cause ?

rsmark86

iTrader: (3)

There's a tool that attachs too an air line

Brake and clutch cleaner on the vac pipes and inlet too see if it reacts too it

wedge07

Mine did this not long ago, my pipe had come out of the back of boost gauge, was fine after that. I'd defo say its boost related

Gem frst

Right not a boost leak but when I unplug map sensor vac and block it will idle lovely?! With it plugged in wont run just wants to cut out dosent make sense any ides

Gem frst

Is it map sensor ?

Gem frst

Is it map sensor ?

wedge07

Faulty map sensor?

Gem frst

Do they just go like that