Rough Idle/cut Out And Maybe Clogged Injectors??

[urchin79]

Hi, I have a 1999 Focus Zetec 1.8 and yesterday it ran very low on fuel (fuel light came on and unluckily one petrol station had roadworks and the next one had no fuel so did a fair few miles hunting!). It seemed fine driving back home but when I pulled into my park space it was really rough erratic at idle and the lights flickered as if it was going to cut out. Today I went to Halfords and got some fuel injector cleaner and gave the car a spin giving it some revs/low gear and it's no better and I pulled back into my parking space and it cut out. :( It also seems today to rev when braking/using clutch but I had clutch changed 18 months ago and not sure if it's related? I hope I didn't hurt the car more by revving it a lot after using the fuel cleaner but someone told me it was best to try and unclog the injectors. I won't be spending much on this car but curious to know what is wrong and if it's safe (roadworthyness) to drive.

Help?

[Andy.B1971]

First thing I would do is replace the fuel filter just to be safe and cheap too :D

[urchin79]

OMG, the idle thing is the least of my worries, it is now driving by itself!!! I take my foot off the gas and it keeps going at the same speed and doesnt slow down at all. I went down a long dual carriageway with no foot on pedal and no loss of revs/speed!!!!! This car doesnt have cruise control btw, but it acts like it does! :S

[jeebowhite]

that is interesting!

I would start by replacing the fuel filter as earlier suggested. How long / far can the car go on driving by itself?

This is starting to sound like you may also have a sticky sensor on the accelerator, perhaps it thinks your foot is still down.

Let it drive itself and see how far it goes before it starts to slow down itself. if its only a few seconds that could be the backlog of fuel getting through the dirty filter (my suspicions at least)

[urchin79]

Oh it's not just a few seconds, it will keep driving same speed/revs for a 1-2 minutes until I brake when I reach a roundabout! When I brake and push the clutch in there is some mega revving most times. And it still sounds rough at idle.

I popped into local garage and man there took it for a drive and suspected something to do with sensor and air leak (think he meant in engine??).There was no time for explanation (need to book it in for an investigation) and I don't really understand what he meant.

Thanks for the replies!

[urchin79]

Ok so I was driving tonight and when I take my foot off the accelerator the speed drops by a couple mph after about 5 seconds. I didn't test to see if it totally drops as heavy traffic behind me so maybe I will try later. Still spluttering at idle, jerking at very slow speed and revving alot when clutch depressed and braking (unless I depress it right at the last second when braking.).

[jeebowhite]

I would start with a fuel filter first then I would be cleaning the idle control valve

[urchin79]

Can I easily learn how to change the filter myself? I am currently clueless and don't even know where it is! lol (although I did learn, but have now forgotten, how to change brake pads some time ago with a friend and it worked out ok... I realised I drove off with 1 wheel not quite on properly but once that was screwed on everything was fine :P)

I can't go spending much more money on this car as the new power steering pump failed and although its under warranty there is no way I can go back to the garage that did this as they are just completely incompetant. This car has to go soon but I need it to get me about til I get a new one.

[jeebowhite]

Fuel filter tends to be cheap and if I recall correctly it's under the engine bay.

[Andy.B1971]

Air leak you can detect yourself, either listen for a high pitch sucking noise on the inlet manifold or sparingly spray GT85 OR WD40 on the inlet manifold area and if the revs pick up in the area you spray you will have found the leak, Give it a go nowt to loose.

[urchin79]

I don't know what the inlet manifold looks like/where it is in my car :( Maybe I will pop into Quikfit in the morning and ask them to do this given it's a quick job. And the filter.

I also read about idle control unit and that someone else had their car drive and revv with no input from them but once they cleaned this it was ok. Anyone else heard of this unit causing this?

Thanks for all the help, i'm getting ideas from friends but mostly along the lines of ghosts, aliens and maybe even it's KITT. lol

[urchin79]

Jeeeez, it's revving a bit when changing gear but when I come to a stop at traffic lights and out the clutch right after braking in it's gone crazy... shot right up to 6 and put in neutral and took foot off clutch but immediately apparent I should quickly cut the engine or it might not stop! I had to turn engine off twice today to stop it going so high Plus the idle is still rough as hell and cut out twice. I am feeling so rushed to get another car. I am not sure mine will last til I can get it to garage for diagnostics anyway. Doesn't seem much point judging by how bad it is.

[jeebowhite]

If I was you I would call a mobile mechanic to come take a look and I suggest you stop driving it as a precaution

[urchin79]

yeah i've not driven it since, but i've been out looking for other cars. If I find one soon I will get mine taken for scrap rather than pay for investigations! Maybe I could call RAC as I have home assistance but not sure if they can diagnose anything then and there? If they could give me an idea it would be great so I have a rough idea. I am tempted to take it back to Mr Clutch tbh as it seemed to rev like it did when that needed doing.