Hi guys, PLEASE help me! I have an 02 zetec se fiesta, its got a de-cat exhaust and 4branch manifold, 90% of the time its running abit rough, think the standard panel air filter has been replaced with a racey 1 aswell if that would make a difference? When its revving at over 3000 - 3500 revs it runs smooth as butter, but lower revs is abit spluttery and on tick over bounces from 900 - 1000revs. I took spark plugs out and cleaned them and also put the airbox back in properly, still not a lot better, and I also unplugged mass airflow meter which made it worse so I'm assuming the meter is not at fault? Any advice would be very appreciated, its my first zetec s I'm used to having xr3i's and xr2s so not sure about diagnosing myself. Cheers for reading hope to hear from someone with some knowledge!

 

Cars getting worse by the minute, the bottom section of the airbox has loads of 20mm holes in it, is this normal or has someone drilled them? Perhaps too much air in the mix? Or cos the de-cat and 4branch I need a re-map?? Any suggestions would help me out people, am getting desperate haha! Cheers

 

Best thing you can do is take it for a tune, the AFR etc can be established, it may be a sensor fault etc.

Has it been serviced?

But yes, you can't just simply bolt mods on and hope they will work, as you increasing the VE, it will run leaner, so the map may need richening up a bit.

Martin

 

as above ^, I have one of these as my daily driver, normally once you start playing about with decats and drilled airboxes etc it can throw all the settings out of bonk, normally route cause of most running issues on a zetec is air or mixture related,

 

Cheers guys, yeah its had a service few k ago, could you point me in the direction of a company / someone in the business of re-mapping? And what sort of money does a tune up/ re-map usually cost on a car like this? Thanks for yur time

 

Cant beleive uve gone from retro to rust bucket? Get rid of it n check out the fiesta rs2000 for sale on ebay

 

I would have said MSD, but as your in Hertfordshire I don't know, any tuner will be able to do it.

It won't be alot, after all it's quite a simple engine (the engine was borrowed from the Focus, if you didn't know)

Martin

 

Hi Dan

I had mk 5 ZS for 4 years. Great wee car apart from the chronic rust problem, but hey it is a ford after all.

Mine started to hunt for revs on idle and when coming to a standstill would hover for a second then drop just after you stopped.

This seems to be a common problem and the Idle Control valve getting sticky was often the culprit. Clean it with carb cleaner and see if that helps, its only two bolts IIRC. I ended up replacing mine which did help the hunting for revs. I also remove the induction kit that I had put on for the standard airbox (it shouldn't have any holes drilled in the bottom btw).

One thing I did notice was very weird was that when the gearbox speed sensor was disconnected the fault completely disappeared. I was told (no idea if true) that this had the effect of feeding the ECU default sensor readings, but which sensor was at fault I didn't know. A lot of people ended up replacing all sorts of parts from donor cars and it can be a lengthy and expensive process.

Good luck mate.

 

Mine used to do this. Was the cylinder head temp sensor. Only 7 quid. Change that and leave the battery of for an hour

 

Hi guys cheers for input, I cleaned the idle control valve this morning and didn't have much of a change, I think will buy a new 1 see if that helps, also trying to hunt a standard airbox down. Zippyobrien u said you had same problem, did yours have decat and 4branch manifold? A friend had told me this could be my problem because of lambda sensor ? So many different ideas I'm sort of lost. Is re-mapping the ecu my best bet if I want to keep these mods?

 

Yeah mine had a decat manifold. Cone filter, few other bits and pieces. Was shit on fuel, hunted and felt flat.

Changed the above sensor and brought it back to life. It's at the back left corner of the head on some cars and bang in the middle between no 2 and 3 plugs on others.

 

Yeah mine had a decat manifold. Cone filter, few other bits and pieces. Was shit on fuel, hunted and felt flat.

Changed the above sensor and brought it back to life. It's at the back left corner of the head on some cars and bang in the middle between no 2 and 3 plugs on others.

 

Cheers mate sounds very promising as symptoms are identical, will try it out! Many thanks will let you know how it goes