Holding back at low Revs

Holding back at low Revs

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Discussion

Soul Reaver

Original Poster:

499 posts

198 months

Sunday 20th September 2009
quotequote all
Hi Guys (rick)

I have noticed on a few occasions now when I am pootling along at almost no throttle (around 50 ish in 6th) sometimes the car will miss (hold back a bit) its like there is a disconnect between the the throttle and my foot. Anyone else noticed this at anytime?

Mark

rick-derby-

1,105 posts

193 months

Sunday 20th September 2009
quotequote all
Hi Mark, Yes i have seen this in varying degrees and different causes, first and the most likely, is a build of deposits on the throttle flap, easily rectified, just requires the large black intake hose removing it's held on with a large plastic clip, then the throttle flap just want a clean with something like carburettor cleaner, then rebuild and try all in all about a 10 minute job, the next is poor connections either at the throttle pedal or the throttle body, just removing and refitting the connections can rectify this, but care must be taken as not to damage the connectors or securing clips, next is an error with in the ecu programming (glitch) a reflash can help or there may be an update to the program, there are other possible causes but these are the common ones, If it's the throttle response that is the issue (lag) This is a general complaint, then a modified ecu program (remap) and a sports rear box exhaust will improve this,

Mark if you want to try the first two then, i can post some pictures or perhaps a video showing how,

Soul Reaver

Original Poster:

499 posts

198 months

Monday 21st September 2009
quotequote all
HI Rick

Great stuff and yes Ill try the first two please smile


mark

rick-derby-

1,105 posts

193 months

Monday 21st September 2009
quotequote all
i will compile a video for you tomorrow, no laughing will be allowed remember i am a mechanic not a blue peter presenter

Soul Reaver

Original Poster:

499 posts

198 months

Monday 21st September 2009
quotequote all
I am quite sure we shall enjoy your efforts Rick and i shall have cleaner in hand ready to go smile

rick-derby-

1,105 posts

193 months

Tuesday 22nd September 2009
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here we are mark a bit of direction and a short video, mmmmm don't think i will give up my day job just yet and go into film production took three attempts to get to this,

http://www.derbymotorservices.com/faq/questions/12...

Soul Reaver

Original Poster:

499 posts

198 months

Tuesday 22nd September 2009
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An excellent little vid Rick thanks. Done both and will keep you posted on results. My throttle flap was very dirty mind you.


Mark

Soul Reaver

Original Poster:

499 posts

198 months

Friday 25th September 2009
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Hi Rick

How much and when can you do the reflash?

mark

XXXAngelXXX

1,711 posts

234 months

Friday 25th September 2009
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Rick you are incredible !

rick-derby-

1,105 posts

193 months

Friday 25th September 2009
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mark i can sort it to suit you price is £900.00 inclusive just let me know if you would like it doing and when it would be convenient, Frank be careful people will start to talk,tongue out

Edited by rick-derby- on Friday 25th September 19:00

XXXAngelXXX

1,711 posts

234 months

Saturday 26th September 2009
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yikeslaughlaughlaugh

sillyboy

50 posts

189 months

Sunday 27th September 2009
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Good to see my 9 in the background, looking forward to getting it back tomorrow.
The R8's good but not that good.

Enzo

trying to help

2 posts

181 months

Wednesday 30th September 2009
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If the car is holding back on almost no throttle and doing the same in cruse (it will be more noticeable going down hill in Cruse) you have probably had a flat battery or disconnected the battery at some time,
If so you will need to carry out a cam learn.
Drive along in 6th gear at 70 mph lift of and coast down to 30mph still in 6th, (do not use the brake) you will need to do this 2 to 3 times. (try to find a flat road and do it over the same piece of road)
To check the car has learned the profiles drive in cruse down a slight hill, it should now be smoother

Soul Reaver

Original Poster:

499 posts

198 months

Wednesday 30th September 2009
quotequote all
A cam learn? What on earth is that? I dont have cruise by the way.

Best
Mark.

trying to help

2 posts

181 months

Thursday 1st October 2009
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The cam learn has various names (flywheel adaption, misfire learn etc) it’s all the same,
Basically it’s were the car learns the fuelling adaptions and misfire adaptions,
It looks like your car has lost this from its memory that’s why I asked if you have had a flat battery or disconnected the battery,
It does not matter that you don’t have cruise, its jut more noticeable in it.
Try the process any way it’s cheaper than a re-flash.

Knights of Aston

311 posts

184 months

Thursday 1st October 2009
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Make sure the A/C is turned off when you do it.

cheviotred

4 posts

182 months

Friday 16th October 2009
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Wondering if the advice here is equally applicable to a 1995 i6 DB7? I seem to have a similar issue - worth my trying the "cam learn" and/or getting the throttle cleaned out?

Thanks in advance ...

Knights of Aston

311 posts

184 months

Tuesday 20th October 2009
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cheviotred said:
Wondering if the advice here is equally applicable to a 1995 i6 DB7? I seem to have a similar issue - worth my trying the "cam learn" and/or getting the throttle cleaned out?

Thanks in advance ...
On the old I6 I'd check the MAP pipe from the MAP module on the N/S/F wing if I were you. It goes hard over time and breaks down inside causing idling problems and such like. You may have to take it completely off and blow down it to be sure. (It goes to the inlet manifold)
Also make sure the ignition cables are good and that cylinder 6 plug hole isn't full of water. There's a handy drain on the scuttle panel that lets water pour straight in!
This only applies to the non-airbag cars though. The ones with the grey instrument cluster. AKA the Zytek cars.

Edited by Knights of Aston on Tuesday 20th October 15:13

cheviotred

4 posts

182 months

Wednesday 21st October 2009
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KoA:

Thanks for the reply. Whether I have a 'series 1' or 'series 2' car is something of a moot point. It's partly series 1, partly series 2 and partly unique, as it's a surviving FEV prototype db7 i-6 volante from 1995, and thus bridges the gap between the series. It has airbags, but much of the insides are series 1 derived, but by no means all. Series 1.5 perhaps?

Anyhow, your comments are very helpful in guiding me to a possible cause. Thank you for this, and for taking the time. The car is now with my mechanic, and I will let you know what he finds ...

Simon.

Edited by cheviotred on Wednesday 21st October 11:35


Edited by cheviotred on Wednesday 21st October 11:35

Knights of Aston

311 posts

184 months

Wednesday 21st October 2009
quotequote all
If it's the earlier Zytek engine there is a CAM sensor at the rear of the CAM cover on the drivers side of the engine. It blends in quite well but there some wires poking out which give it away.
Hope he finds the fault.