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Revs High / Idle problem help!

Revs High high idle

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#1
suprezmo

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Hi,

 

Really hoping someone can help as not sure what else the problem could be! 

 

For a few weeks now I've had trouble with my revs. The car sits idle at around 1500RPM and constantly over revs in between gear changes and occasionally on its own. I have had a mobile mechanic look at it twice now, and he has ruled out pretty much every possibility. The revs only seem to drop when the clutch is half engaged but when fully engaging they rise to over 3000 and taking foot off completely they continue to sit at 1500.

 

So far I have changed the throttle body (as originally had fault codes P2107 and P2110 shown up. I have tried resetting the ECU and draining its memory and neither of these worked. The mechanic managed to rule out almost every sensor on the car, and diagnostics also read that the throttle itself was working as expected. He has taken the EGR valve off and given it a good clean, and that seems to be working properly. He said he couldn't find any evidence or signs of a vacuum leak. The only sensor left which he struggled to get to because of its location was the MAP sensor. He tried spraying carb cleaner on it from where its located and was able to disconnect it (but still no change). 

 

Does anyone have any other ideas as to what the problem could be?

 

I'm so stuck now I'm not sure where to start!

 

Any ideas would be much appreciated! 

 

Thanks 


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#2
Silverthorn

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@suprezmo Have you had a look at the PCV to inlet pipe? They are common to split and cause a vacuum leak causing the revs to rise to about 3k between gear changes before falling again.

 

I have exactly the same issue currently and will be sorting it relatively soon. The pipe is about £30 from ford but it's a bit of a pig of a job to do as the pipe is sat in between the inlet manifold and the engine block. 

 

I'll most likely be removing my inlet to do the job as i'm taking half the front end of to do some other bits at the same time


https://www.fordpart...30644_c_472.htm

 

Here's the link to the pipe from ford parts. If you search duratec PCV pipe online you'll find a few threads about it and a handy youtube video showing how to change it if you fancy doing it yourself



#3
suprezmo

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@Silverthorn thanks for your reply. really appreciate it. 

 

I did wonder if the PCV to inlet pipe could be the cause - had seen a lot of posts with the same issue. How difficult is it to remove the inlet manifold?

 

The car now seems to have got worse since the mechanic's efforts today. I wasn't even able to drive it home this evening as it kept constantly going to EAC fail and going into limp mode. Had to get the AA to tow me home so it's now on the driveway :(

 

The revs also seem to have got even worse - now rising to between 4000-6000RPM when before it would barely go over 3000RPM! It's so strange - the last part the mechanic fiddled with today before he left was the MAP sensor but he decided against taking it off in the end as he wasn't convinced he could put it back with it being out of view. 

 

Concerned about taking it to a garage as I'm sure they'll charge me to carry out checks on all the things it's already been checked for! 

 

Thanks



#4
Steve

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That sounds like that pipe right under the inlet as people have said above. Same thing happened to me. If you even press the accelerator lightly the revs almost redline. Mine was split like a banana skin. It is only a short length.

 

If you shine a torch down through the inlet just right of centre you might be able to see the exposed orange pipework where the black hose should be covering it.

 

As said above it is an expensive item for the size of it and job is made harder because you can barely see it and everything is in the way. Get someone with a good toolkit to help you out and should be cool. When all back together you will wondering how your car could seem so poorly from such a simple thing. Good luck.



#5
suprezmo

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@Steve @Marv_st thanks for your responses.

 

Will try and investigate tonight. Damn annoying I can't have a good look at it during the day because of work. If I'm unable to see anything myself I'll consider removing the inlet or taking it to a local garage.

 

Do you have to wait some time for that part from Ford?

 

Thanks



#6
suprezmo

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@Marv_st great thanks!

 

You wouldn't happen to know of any detailed guides/videos on how to remove the inlet manifold would you? 

 

I'm really hoping it is the pipe that's split so I finally know what the culprit is after so many weeks!

 

Thanks



#7
Silverthorn

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@suprezmo There's a guy on Youtube called 'Craig's DIY Car'. He's done a good video on the removal process. If you google duratec inlet manifold removal his video will show up.

 

Here's the link (hopefully it works, but I can't actually open it to check as I am at work :lmao: ):

 

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#8
Jonesy

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@suprezmo Have you had a look at the PCV to inlet pipe? They are common to split and cause a vacuum leak causing the revs to rise to about 3k between gear changes before falling again.

 

I have exactly the same issue currently and will be sorting it relatively soon. The pipe is about £30 from ford but it's a bit of a pig of a job to do as the pipe is sat in between the inlet manifold and the engine block. 

 

I'll most likely be removing my inlet to do the job as i'm taking half the front end of to do some other bits at the same time


https://www.fordpart...30644_c_472.htm

 

Here's the link to the pipe from ford parts. If you search duratec PCV pipe online you'll find a few threads about it and a handy youtube video showing how to change it if you fancy doing it yourself

 

 

dunno where you've got your price for the part from but i only paid £8.20 for it :)



#9
Steve

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Honestly don't bother fitting anything that isn't right. My auto-electrician found a near perfect match but due to location and size it just kept on popping off and kinking when being offered back in to position. After seeing the faff of it all I would get a new one. The feel of the perished one versus the new one means that hopefully I have years of piece of mind. No point paying someone only to have to re-visit the job.

 

Good luck to anyone who fins one cheaper but even with a good discount mine was over 30 quid from Ford. As expensive as this sounds if you're anything like me then you'll find that quite cheap when you thought your car was gonna blow up from revving so high.

 

Good luck.



#10
Jonesy

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@Jonesy. I thought it was pretty obvious @Silverthorn got his price from the link he posted in his comment...

 

Help the lad out and post a link/explanation of where you got yours from?

 

just rang ford uppart number is either GG9G-6758-aa or 669G-6758-aa.

 

The picture i took of is blury, like i said, just rang ford up and had it that day. £8.20 odd from memory


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#11
Silverthorn

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I don't suppose by any chance anyone knows the inner diameter of the PCV hose? After reading up online about it I'll most likely just run a pipe to a catch can and breather filter and then just blank off the inlet side of it.



#12
###simon###

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Have a look on FF inlet thread, the sizes will be on there.

#13
Silverthorn

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@###simon### Ah perfect thanks, I'll have a read now  :nice:



#14
Silverthorn

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@Marv_st Awesome. Thanks mate



#15
stuey2407

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I know its an old thread but my mk7 st180 has exactly the same symptoms. Is the pcv hose in the same place on the mk7?




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