|
|
Post by rhyds on Jun 27, 2015 22:39:34 GMT 1
My Focus has always had a slightly rough idle ever since I bought it. It's perfectly stable, but if you put any load on (A/C or electrical via headlamps or heated screens) the idle speed drops and you can feel the engine vibrating through the steering wheel. Raise the engine speed with the throttle and you're fine.
Another odd thing it does is that if you boot the throttle hard from tickover with the engine unloaded the engine will hesitate momentarily before reving up. You usually can't feel this during driving, but every now and again the engine hesitates for half a second before accelerating normally.
The car hasn't seen much in the way of servicing before I bought it, but I have changed the air filter and spark plugs to try and improve matters with limited success.
Am I right in assuming the hesitation is probably duff HT leads or a coil pack? Anyone got any ideas on the idle speed issue?
|
|
|
|
Post by Rhubarb on Jun 27, 2015 23:01:35 GMT 1
Sounds pretty normal for one of these, they're not the smoothest of engines  |
|
|
|
Post by Karl on Jun 27, 2015 23:27:27 GMT 1
Sounds like it's just the extra load from the generator demand , and PCM strategy isn't quick enough to respond. ( don't forget 17 year old design )
So it's not a misfire , but a delayed throttle response ? Does this effect drive ability ?
|
|
|
|
Post by rhyds on Jun 27, 2015 23:33:07 GMT 1
The hesitation is more a missfire than a simple delay, imagine an old mini with no oil in the carb dashpot. Driveability seems unaffected at the moment and the car responds how you'd expect it to when you whack your foot down.
|
|
|
|
Post by Karl on Jun 27, 2015 23:39:21 GMT 1
Both concerns sound normal to me
But it might be useful to have a spare ignition coil , even if it makes no change
|
|
|
|
Post by Noberator on Jun 27, 2015 23:46:14 GMT 1
Could the Idle Air Control valve be slightly restricted?  |
|
|
|
Post by mayfly on Jun 28, 2015 10:58:09 GMT 1
Does yours have a MAF. Had a focus last week with rough idle and cutting out occasionally at junctions. Maf was duff. Did you scan it?
|
|
|
|
Post by rhyds on Jun 28, 2015 11:27:43 GMT 1
I only have a £25 code reader, but I'll have a nose. There's no EML and most of the time it drives fine. To be honest I'm probably worrying over nothing.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jun 28, 2015 16:55:49 GMT 1
I only have a £25 code reader, but I'll have a nose. There's no EML and most of the time it drives fine. To be honest I'm probably worrying over nothing. Any drivability issues with these you have to start at the ignition ,the leads go high resistance and leak ,the coil packs short and the plugs often get ignored for years, after that its a lean mixture problem . |
|
|
|
Post by rhyds on Jul 2, 2015 12:51:46 GMT 1
I popped over to see a mate who had a spare Bosch coil pack, unfortunately it was the wrong plug for my focus, so I'm after another.
Where's the best place to get a decent coil pack these days? And what's the best brand for a focus?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 2, 2015 15:50:06 GMT 1
leads first then coil pack and thats if it is ignition , luckily for diy parts swapping these are cheap but there is cheap junk too.
|
|
|
|
Post by Monkey on Jul 7, 2015 9:26:17 GMT 1
Bosch coil packs are the modified fitment for these.
|
|
|
|
Post by rhyds on Jul 7, 2015 9:33:34 GMT 1
Thanks for the advice guys. As it happens GSF had a 35% off offer last weekend so I went for a new coil pack and HTs. Might get a chance to fit them today.
|
|
|
|
Post by rhyds on Jul 7, 2015 12:35:19 GMT 1
Just back from a test after fitting the new coil and leads and the car seems a lot happier. No hesitation when blipping the throttle in neutral and it seemed to pull better through the rev range under load.
The new coil pack was a BBT branded item. The design was different to the one I took off which had no makers markings or part number I could see. The old coil pack had the coils fitted from the bottom of the pack then expoy filled, and the pack then sat flush on the mounting bracket. The new unit had the coils fitted from the top and the pack itself sat higher off the bracket and was supplied with longer screws. I assume the original design suffered from overheating.
The HT leads I took off were Motorcraft ones, so I guess about 10 years old. The new ones were "electrospark" double sillicone. Not the most expensive of brands but worth a go. I have of course kept the old leads and coil (complete with mounting screws) as spares.
The idle speed is still playing up when you put the A/C or heated screen on, but I'm thinking that might be a throttle body and idle valve in need of a good clean out.
|
|
|
|
Post by chippie on Jul 7, 2015 13:45:14 GMT 1
The idle speed is still playing up when you put the A/C or heated screen on, but I'm thinking that might be a throttle body and idle valve in need of a good clean out. Surely that's the engine speed increasing due to increased load on it? And is normal I'd have thought.... Most Fords I've had exhibit this inc the missus 63 plate Fiesta.....less noticeable on my Passat which is diesel....  |
|
