Slow throttle return and tricky pull away 1.8 NC

Most cars I have had you could blip the throttle and the engine revs quickly reduce or return to idle but my 1.8 NC seems sluggish and blipping is not really possible. Seemingly connected to that is a tricky method to pull away. The normal blending of throttle and clutch at reasonable revs has to be replaced by higher revs to achieve a smooth pull away.
Is this a normal trait for a 1.8 NC (2012 / 3.5) or is there a known fix (or two)?? I guess I really need to test drive another 1.8 to compare but don’t know of any close by (Horsham, West Sussex)

Not a reply as such, however just got a 2013 1.8 and am having the same issue. Its not all the time but i would say more often then not where i have to rev more than i would thought normal and ride clutch to get away with out engine staeting to stall.

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Thanks for that, I’m glad to know I’m not alone. Do you feel that blipping the throttle is normal? I believe these cars are “drive by wire” so I’m not sure how any adjustment can be made.

Well being as there has been no response to this, suggestions of a sensor at fault etc a simple one to check, are the battery connections clean and tight?
Secondly these engines running learn via the ECU so if either one of you has recently had a battery change it does affect the running on reconnection, especially idling and could cause stalling issues until the ECU has relearned
You’ll probably come back and say yep but I’ve not had the battery off etc. Worth checking the connections all the same, infact disconnect the battery clean up the connections and try again.
If you do disconnect the battery then make sure your radio head unit isn’t coded, you’ll need the code obviously on reconnection of the battery. Aftermarket head units no problems with codes.
Once the battery has been reconnected leave the car idling for around 15-20 mins then drive it, see how it goes.

Just something simple to try, if not solved then you need a technician.

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Hi
Yes they are a little lazy to respond to throttle blipping, if re mapped we can sharpen the throttle up.

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The good news: it’s not your driving and it’s easy to fix.

The bad news: you may need to book an appointment with your chiropractor after you fix it.

One if the benefits of electronic throttle is different pedal maps for each gear. What this means is that in each gear, the actual throttle butterfly responds differently to the same demand made by your right foot.

Not only do you get a different pedal map for each gear (all forward and reverse gears)…you also get a pedal map for launch/pull away from standstill.

When you experience a launch with a unexpected rev-flare, the clutch pedal switch has not been triggered to tell the car it’s a launch condition and you get the wrong engine torque response for your pedal demand, either overshooting or undershooting revs. It all conspired to make it look like you can’t drive properly.

Check the clutch pedal switch is moving correctly - it may be sticking. I have the same symptoms as you. I will check mine and report back to you.

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Oh yeah, forgot to say that if I get no joy from the pedal switch, I am also going to check the throttle itself. Just a quick look to see if it clean or excessively dirty inside.

Not saying this is definitely the problem but I will systematically go through a process of elimination until I find the issue or throw in the towel.

Thanks everyone, I’ll work my through the ideas and see how it goes. Well apart from the remapping for now.

Hmm, I’m probably completely wrong here, but some different cures for something a bit like this have been found by others (alas, I can’t find the references now).

One was a broken pedal mount bracket

Another was over advanced ignition setting (but how on NC?) - highlighted by a couple of tanks of V-Power sorting it (almost). V-Power often fixes the ‘starting to stall’ problem.

And has the EGR thrown any fault codes?

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Checked the clutch switch and found nothing wrong in the action/movement of the switch. Gave it a quick spray with IPA, as a precautionary clean, and pushed it in-and-out a few times.

Removed the rubber elbow that goes from air filter housing to throttle body. I didn’t remove the throttle body from the intake manifold - I left it in situ.

I wrapped a clean cloth soaked in petrol around my index and middle fingers and carefully cleaned the inside of the throttle body. It was full of black gunk and I had to keep adjustng the cloth around my fingers to find a clean bit because it was getting dirty so quickly.

I cleaned both sides of the throttle body - before and after the butterfly valve. You can gently push against the butterfly valve to open it and get the cloth further into the throttle body.

I was genuinely surprised how much gunk there was in the throttle body. I am not sure if this impeded the function of the device or affected the airflow at small throttle openings, but…there is a definite improvement in the way the car behaves during pull-away and idle drive.

I can now manoeuvre the car around at walking pace on the clutch without any input from the accelerator pedal. Pulling away from junctions and traffic lights is a lot more controllable and civilised - overshoots/undershoots have been eliminated.

I am now much happier with the low speed drivability of the car. I hope this improvement lasts.

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Hi Richard, the pedals all seem fine, good movement and no sticking. As the MX is a hobby car it’s spoilt on V Power or premium fuel so that’s also checked off. No fault codes pending or stored.

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Sounds like a result.
Sounds like a very simple solution too.
Will give it a go and report back. My NC2 has never been happy to manoeuvre just using idle speed.
Even the wife’s gutless eco Panda is better

Had a go at cleaning the throttle body this afternoon
I found it simpler to disconnect at both ends and move the connecting pipe out of the way.
The inside of my throttle body was coated with black gunge too but as the egr system connects just downstream of the throttle body, thats not terribly surprising.
The black gunk was limited to the downstream side of the butterfly though, upstream was pretty spotless.
I cleaned the back of the butterfly and downstream from the butterfly as best I could with rag and carburettor cleaner, then reassembled. Very simple job.
Haven’t had a chance to try it yet, will report when I do.

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Tried it last night.
Hardly a scientific appraisal but I noticed little difference.
Maybe I wasn’t thorough enough.

Don’t worry I am waiting for my “perceived” improvement to turn to dust, and look like a kangarooing idiot, the very first time I get stuck in heavy traffic.

The problem is this issue could be caused by a myriad of things… including things we haven’t thought of, such as engine and transmission mounts, clutch issues, clutch hydraulics…

The only solution is to drive the bloody things and worry less.

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Many years ago we rebuilt the sweet 9FA engine in a Mini Cooper. It had been standing for a while…

We cleaned up the flywheel, ie removed the caked friction material and rust film from the lower half and put in new competition pressure plate and competition friction plate.

That proved to be the ultimate kangaroo, simply because we cut corners and didn’t skim the flywheel to remove ALL traces of the rust. including the pitting.

Much muttering ensued.

It was OK in the end, but an initial three day job turned into a two week one simply because of finding time on a local lathe big enough.

Remapping sorted mine. plus a smoother drive and better mpg. only plus 9bhp but well worth it neverthless.