2005 Ford Focus 1.8TDCI Rough Idle - Causes?

littlemiss123

I recently bought a 2005 1.8 TDCI Ford Focus and have noticed it is quite rough in idle.

The revs fluctuate very slightly when first starting the car but this is only noticed when looking at the rev counter, the car doesn't shake.

However it seems to get worse when the car is warm. About every 20 seconds it gives a good shudder and shake as if it's going to choke, but this only last a few seconds and then it idles smooth again.

The car was sitting up for 2 months before I bought it so I'm wondering (or more hoping...) could it be something as simple as dirty injectors that could be resolved with an additive? Or could it be something more costly?

I don't seem to have any issues when driving, although the MPG is lower than I was expecting (dial reads ~40 mpg), but this could also be down to the fact I like to put the shoe down

Any ideas what could be causing this?

Bpmull

I'd start with the basic oil air fuel filter and fresh oil. I'm not saying that's the problem but you might as well do that first and see if it helps. I think the 1.8 is abit noisier than the 1.6tdci. But I don't no much about the 1.8tdci.

Celly Smunt

Try cleaning the throttle body.Does it act as if it is going to konk out?

littlemiss123

It has a oil and filter change before I bought it (...supposedly) so I don't think that's the problem.

It doesn't act like its actually going to conk out, just shudders and the rev drops, but not low enough that it will cut out.

Bpmull

littlemiss123 wrote: »

It has a oil and filter change before I bought it (...supposedly) so I don't think that's the problem.

It doesn't act like its actually going to conk out, just shudders and the rev drops, but not low enough that it will cut out.

If It was you I'd open the air box and have a look at the air filter if that's dirty chances are the car needs a full service. Its the simplest way really to see if it has been serviced. It would literally take about a minute to check the air filter anyway.

Celly Smunt

is the engine getting fierce hot at all?

littlemiss123

Yeah, I'm thinking I might as well put it in for a full service cos you can never be sure these things have actually been done. I'm just afraid that I'll be told its something more serious....it's everyone's worse nightmare when you've just bought a new car!!

pmcmahon wrote: »

is the engine getting fierce hot at all?

No the engine temperature is fine, done a few long journeys in it and temperature has stayed well within the normal range.

Celly Smunt

littlemiss123 wrote: »

Yeah, I'm thinking I might as well put it in for a full service cos you can never be sure these things have actually been done. I'm just afraid that I'll be told its something more serious....it's everyone's worse nightmare when you've just bought a new car!!



No the engine temperature is fine, done a few long journeys in it and temperature has stayed well within the normal range.

I think a service is probably the best option,wherever you go just point out the problem and ask them to look at the throttle body.It an easy job,just a clean so i doubt they'll charge you anything extra as no parts or anything will be used.

Big Davey

If you are able take out the throttle body and clean it a carb cleaner or similar and use a soft bristled toothbrush I have had several cars with that problem and it worked all but once when I needed a new throttle body. Also check air intake pipes for cracks / splits etc
Good luck.

maidhc

A diesel doesn't have a throttle body!!!!

Sounds like an EGR type problem. To be honest I had a 1.8TDCi and half the time it was down on power, and MPGs were not what they should be. It still ran and I just drove it.... There was never anything clearly "wrong".

Start with the simple things. Put in a full tank of fresh diesel, some additive and drive the bejazus out of it.

mullingar

A 8 year old 1.8tdci?

The DMF is near guaranteed to fail on them at around 100kmiles.

But asthe fault is only when warm, im leaning towards ths EGR. Just blank it off and see if it fixes the fault first.

maidhc

mullingar wrote: »

A 8 year old 1.8tdci?

They came out in 2001!

mullingar

maidhc wrote: »

They came out in 2001!

That 1.8 dates back to the Sierra. It was 2004ish when it went TDCI.

maidhc

mullingar wrote: »

That 1.8 dates back to the Sierra. It was 2004ish when it went TDCI.

Nope, went TDCi in 2001. The TDDi was still sold up to 2005 when the Mk2 came out. I had an 03 TDCi.

Back then you had the option of a 90bhp TDDI, 100bhp TDCi or 115bhp TDCi.

George Dalton

maidhc wrote: »

Back then you had the option of a 90bhp TDDI, 100bhp TDCi or 115bhp TDCi.

There was also a 75bhp TDDI for those who really hated life :pac:

littlemiss123

maidhc wrote: »

A diesel doesn't have a throttle body!!!!

Sounds like an EGR type problem. To be honest I had a 1.8TDCi and half the time it was down on power, and MPGs were not what they should be. It still ran and I just drove it.... There was never anything clearly "wrong".

Start with the simple things. Put in a full tank of fresh diesel, some additive and drive the bejazus out of it.

Ya, I'm swaying towards the EGR valve, a friend has mentioned he think this may be the problem that it just needs a good clean out. Hopefully that and the additive should clean it out! Like you said, there's nothing 'wrong' with it, just very annoying when sitting in traffic.

I doubt very much it's DMF failure and I don't have any audible rattle when driving or when releasing the clutch even though I am on the watch for it as it has 125k......fingers crossed I get a bit of use out of it first before I have to fork out €1,500

Big Davey

maidhc wrote: »

A diesel doesn't have a throttle body!!!!

Sounds like an EGR type problem. To be honest I had a 1.8TDCi and half the time it was down on power, and MPGs were not what they should be. It still ran and I just drove it.... There was never anything clearly "wrong".

Start with the simple things. Put in a full tank of fresh diesel, some additive and drive the bejazus out of it.

True lol I did not read the post properly I thought it was a 1.8 petrol.

Plug

Generally the EGR valves don't give bother on these. I've only came across one and that was an electrical problem with it. The manifold and EGR are one unit so its a bitch of a job and an expensive part.

I wouldn't think the EGR valve is the cause of this rough idle. Sounds something simple like the fuel filter, and the fuel filters in these if dirty enough can cause your symptoms. Replace the fuel filter if it hasn't been all ready been replaced recently.

Plug

Forgot to say is it a mk2 we are dealing with here?

littlemiss123

Forgot to mention, if I tap the accelerator just the slightest amount when it start to shake it goes away and idles normally again for another 10-15 seconds before it does it again.

Would that be typical of a dirty EGR or more injector related?

shamwari

George Dalton wrote: »

There was also a 75bhp TDDI for those who really hated life :pac:

That one is in the Fiesta only I think

shamwari

maidhc wrote: »

A diesel doesn't have a throttle body!!!!

That particular engine / application doesn't but its newer 1.6TDCi sibling definelty does. Newer uses of that 1.8 in the Mondeo and SMax may have a TB as well but I'm 100% suire.

George Dalton

shamwari wrote: »

That one is in the Fiesta only I think

It's in the Focus as well. I have only ever seen one though.

maidhc

shamwari wrote: »

That particular engine / application doesn't but its newer 1.6TDCi sibling definelty does. Newer uses of that 1.8 in the Mondeo and SMax may have a TB as well but I'm 100% suire.

Really? Sounds more like a pointless flap to break make the car run more efficiently. Definately not a requirment in any diesel engine as the acceleration is controlled by the fuel pump, not the air intake.

George Dalton

shamwari wrote: »

That particular engine / application doesn't but its newer 1.6TDCi sibling definelty does. Newer uses of that 1.8 in the Mondeo and SMax may have a TB as well but I'm 100% suire.

It isn't a throttle body in the same sense as a petrol engine though even though it looks the same. It is an anti shudder valve and is only used to help the engine to shut down smoothly when you turn off the key.

littlemiss123

Plug wrote: »

Forgot to say is it a mk2 we are dealing with here?

May sound a little stupid but what's an mk2?

It's the newer model of focus that came out in 2005 if that's what you mean...?

Bpmull

littlemiss123 wrote: »

May sound a little stupid but what's an mk2?

It's the newer model of focus that came out in 2005 if that's what you mean...?

It's a mk2 then the newer model.

Stella Virgo

littlemiss123 wrote: »

I recently bought a 2005 1.8 TDCI Ford Focus and have noticed it is quite rough in idle.

The revs fluctuate very slightly when first starting the car but this is only noticed when looking at the rev counter, the car doesn't shake.

However it seems to get worse when the car is warm. About every 20 seconds it gives a good shudder and shake as if it's going to choke, but this only last a few seconds and then it idles smooth again.

The car was sitting up for 2 months before I bought it so I'm wondering (or more hoping...) could it be something as simple as dirty injectors that could be resolved with an additive? Or could it be something more costly?

I don't seem to have any issues when driving, although the MPG is lower than I was expecting (dial reads ~40 mpg), but this could also be down to the fact I like to put the shoe down

Any ideas what could be causing this?

check to se if your car an 02 sensor in exhaust system,most diesels dont,but some do have them further down the system,take it out and clean all the soot/carbon off it,ps dont forget to check/replace your air filter. a dirty air filter will reduce power,heavy on fuel,and general bad running.same applies to the main engine diesel filter.

Plug

littlemiss123 wrote: »

May sound a little stupid but what's an mk2?

It's the newer model of focus that came out in 2005 if that's what you mean...?

Yeah mk 2 is the newer of the old ones. So yeah take the advice giving and change the fuel filter.

Plug

George Dalton wrote: »

It isn't a throttle body in the same sense as a petrol engine though even though it looks the same. It is an anti shudder valve and is only used to help the engine to shut down smoothly when you turn off the key.

Main thing it does is assist EGR, when it shuts(not fully) it will produce a vacuum in the inlet manifold so more EG will be fed into the engine. And also as you said.