Citroen C5 2.0 HDI - Story So Far - Synergy Fitted and MPG

[timborob]

Hi All

I have the Synergy fitted to my 2.0 Hdi Auto for about 7-8 months and regularly get 44-45 mpg (brim fills) on 3-600 miles per week perks of an auto I guess!

Have it on setting 6, on 9 had a tendency to spin the wheels!

Haven't timed etc. but the difference is very impressive and the advantage over the remap is you can change the settings or switch it off which I have done on a few occasions to remember what it felt like and at next layby always switch it back on!

For more info http://tuning-diesels.com/ good guarantee and the rover ron very helpful prior to purchase and after for fitting.

I got my garage to fit mine on service as to get to the plug was tight if I remember fuel filter was moved to get to it. Also added ZX1 which one never knows if oil additive makes any difference.

Do use Millers Diesel sport plus whatever its called now and that does make noticable difference and use only Shell fuel who now owe me about 20+ litres since introduced as I don't seem to be getting the extra litre per tankful as per the blurb, One can dream!!

At recent MOT tester asked if I'd had it boosted?

Kevin

Hi Kevin

Thats interesting as I find it hard to spin the wheels of my C5 even in the wet, Maybe its my laid back driving style ?

There again I fitted the Tuning Box due to a feeling of lack of power so mabe i have a lean running C5 diesel

I'd expect if i drove my car at the usual 70 mph on the motorway that and hustled along i'd be getting MPG closer to your 45 mpg

I will have to turn my box off at sometime to remind me how bad my
car was without it on but reluctant to do that just yet!

[myglaren]

Hi All

I have the Synergy fitted to my 2.0 Hdi Auto for about 7-8 months and regularly get 44-45 mpg (brim fills) on 3-600 miles per week perks of an auto I guess!

Have it on setting 6, on 9 had a tendency to spin the wheels!

Haven't timed etc. but the difference is very impressive and the advantage over the remap is you can change the settings or switch it off which I have done on a few occasions to remember what it felt like and at next layby always switch it back on!

For more info http://tuning-diesels.com/ good guarantee and the rover ron very helpful prior to purchase and after for fitting.

I got my garage to fit mine on service as to get to the plug was tight if I remember fuel filter was moved to get to it. Also added ZX1 which one never knows if oil additive makes any difference.

Do use Millers Diesel sport plus whatever its called now and that does make noticable difference and use only Shell fuel who now owe me about 20+ litres since introduced as I don't seem to be getting the extra litre per tankful as per the blurb, One can dream!!

At recent MOT tester asked if I'd had it boosted?

Kevin

Hi Kevin

Thats interesting as I find it hard to spin the wheels of my C5 even in the wet, Maybe its my laid back driving style ?

There again I fitted the Tuning Box due to a feeling of lack of power so mabe i have a lean running C5 diesel

I'd expect if i drove my car at the usual 70 mph on the motorway that and hustled along i'd be getting MPG closer to your 45 mpg

I will have to turn my box off at sometime to remind me how bad my
car was without it on but reluctant to do that just yet!

I've had mine spin it's wheels a time or two - I have to emerge from a concealed entrance when leaving work so have to make it as rapid as possible to keep out of the way of the speed merchants who think the traffic lights are the start of an F1 race and come tearing down the hill at lots of miles per hour.
I always consider mine rather sedate.

[citroenxm]

I think the C5 110bhp 2.0 HDi's are quite sedate, with no ball of fire, were as the Xantia Goes Like F++++ with the 110bhp in it...

Hence my reasoning for the Xantia being a lot lighter then the C5.. The 110bhp Xantias also average 50mpg, were the C5's ive seen avereage 42mpg...

Paul

[Citroenmad]

Ive just had a look on that site, seems like a good price if its that good.

Well with a remap im guessing it will take it to around 135bhp, similar to the later 16v 2.0HDi, which pulls very nicely. So a remap and a tuning box is surely a disaster waiting to happen! Maybe not, but i wouldnt want to put that much stress on my engine, or clutch. I know they are made to take more power etc, but im looking for it to last.

I dont find my C5 sluggish, ive said many times that ive driven a few C5s now and they all seem to differ. MAF seem very sensitive on these and a failing one, or even a dirty one, can effect performance and MPG. I often give my car and the other two C5s a clean out with air intake cleaner, they go much better after this.

I drive my C5 hard most of the time, i think more performance wouldn't go amiss but as it is its ok. As it was a C5 i was wanting and i wanted to avoid the 2.2 136 as it has the FAP and a few other issues, i was stuck witht he 2.0 110, which i like. I dont think a C5 is ever going to feel fast, they are too big, cocooned and refined for that, but its one thing feeling lively, its another being it. The C5 is quicker than it feels, or it should be. Our old C5 estate was a 2.0HDi 110 with 105K miles, it was a real slug, it would move and if you had not driven another you might think it was normal, but it wasnt a patch on mine or the other 110 we have now. A replacement MAF (even though no lexia message was recorded) did improve things, but it was never as quick.

I say quick and fast, but thats relitive to what it is, they are not quick cars, 110 bhp in a reasonably heavy car (lighter than they look and they are actually lighter than a Xantia!?!?! dont know if i believe that, there aint much in it though) is never going to set the world on fire. I can only imagine how a 2.0HDi 90 C5 estate fully laiden and possibly with a caravan in tow would be like, driving it would be some kind of torture!

If you wanted a quick car then the 2.2 173bhp C5 might be the best way! Although they are always going to be softly sprung and be a bit vague to drive - its in their nature, if it was a BMW then ...

Im very pleased with mine, performance is adequate (thats a good term for it), MPG is good and handling, although a bit vague, is actually very good. Grip is very strong, its rare anyone beats me around a bend! I think the 16" wheels help, and possibly a few revisions along the C5s life, as the earlier ones feel a bit iffy. There is body roll and the steering isnt full of feel, but its is predictable and i even find it quite enjoyable to throw around - hence my tyres last 10K!

So in short, i would like a bit more performance, but a 110 should not be slow (im sure a 24sec time from 30-50 can't be right!). I think id like to go for the remapping route, its something ive put to the back of my mind, though i might look into getting that done. I know of the place and the price, i just need to sort my insurance and get it done.

As for MPG, im not sure, we all drive differently and live in different areas. But my car on a good run will reach a trip computer MPG of around 42-45 - i find this figure is actually 3-4 MPG under what i get when i check it brim to brim. Though i never stick to 55-60,, usually motorway speeds ... I did a test once with the cruise set to 60, over about 100 motorway miles it did 61MPG on the trip, i was very impressed with that, but conditions were perfect and traffic was light. Usually my foot is down, as is the economy.

[timborob]

Hi again Chris

I expect a 2.0 16v HDI remapped with a tuning box and new clutch would be the perfect combination for me.


I have read a remap and Synergy together does work well
Have a look at this link where they were both fitted to a 2.2 Mondeo engine with success
:
http://tuning-diesels.com/Jagx/jaghome.htm

I didn't find my C5 slow as such but the throttle response and poor torque
gave a hard vibrating biting point as if it would stall and that has now virtually gone away since putting the tuning box on setting 9.

I'd described my car to being like your old estate car then so it
looks like I will be getting a new MAF on my next service.
It is probably worn on my car and I'd expect better performance will come from my car when a new one is fitted.

I know I will have to buy an original one due to the aftermarkets being rather bad.

Can you confirm the price of an orinigal being around £70?

Sounds like my taking it easy MPG is right then as matches your 61mpg
showing up on the trip computer, Also as I said before I got an average of 42 mpg when driving at a faster pace and at a steady 70 mph with some town work mixed in.

I think if i was to do a brisk 70mph motorway only run that MPG would
still top 50 mpg which is still very good in my book, that will be a test for another day!

[timborob]

Ive just had a look on that site, seems like a good price if its that good.

So in short, i would like a bit more performance, but a 110 should not be slow (im sure a 24sec time from 30-50 can't be right!). I think id like to go for the remapping route, its something ive put to the back of my mind, though i might look into getting that done. I know of the place and the price, i just need to sort my insurance and get it done.

.

Would be good to see some comparison times of your 30-50 etc

At 30 mph in 5th gear my car is showing around 1,000 rpm and before
the tuning box was fitted would take about 15 seconds of that 24 seconds to get to 1300 rpm and then it would pick up quicker from there.

Is there a problem with my car and the tuning box has now masked/solved it.

or is yours the same?

[Citroenmad]

Hi Tim,

Your planning a remap for your car too? What power do you think that would give altogether?

There shouldn't be any vibration through the clutch on the biting point, a vibration could suggest a worn DMF or warped/contaminated clutch plate. It is odd that this has virtually gone since fitting the tuning box, possibly the engine is running smoother? Though more torque will increase clutch wear.

This is another reason i think there needs to be a suitable performance up-grade rather than going all out for maximum power. I want my DMF to last and putting much more power through it will make it give up faster, im sure.

Our previous C5 estate was having running problems, the Citroen indy fitted a new MAF sensor just before we bought the car from them, but it was not a genuine Citroen part. The car felt slow and to eliminate things i swapped the MAF with the one from my C5 which made the estate drive much better, much more like it should have been. So we got a new one from Citroen for it, i think it was around £100.

My car averages 40.9MPG on my trip computer most of the time with my daily driving, which is a right mixture, town, motorway, B roads and heavy city centre traffic, usually without sparing the limited horses! I find my trip computer under reads by around 3-4MPG on what i actually calculate, so it really does 43-44MPG on average. On a run it will do 50MPG without too much problem, sitting at 70-80... Im impressed with the MPG.

Ive no idea what mine would do 30-50, im never in 5th by that point. Though i guess i could have a try and see what it does! 5th at 30 is about tickover, 1000rpm.

I doubt there is a problem with it, though it might be worth getting it on a Lexia to see if there are any codes come up. Its very interesting to see how a Lexia actually works and what it can do, im thinking of getting one.

Im still thinking about a remap, thats the route i want to go if i do decide to improve performance, which would be nice.

[timborob]

Hi again Chris
Here's some answers to what you said

Hi Tim,

Your planning a remap for your car too? What power do you think that would give altogether?

I would love to get it remapped too but alas funds are too low for now
I'd expect our C5 could put out over 150 hp with both tuning box and remapping done by someone such as
http://reidyremaps.co.uk/?page_id=45

After alot of rolling road tuning aswell as other mods

There shouldn't be any vibration through the clutch on the biting point, a vibration could suggest a worn DMF or warped/contaminated clutch plate. It is odd that this has virtually gone since fitting the tuning box, possibly the engine is running smoother? Though more torque will increase clutch wear.

This is another reason i think there needs to be a suitable performance up-grade rather than going all out for maximum power. I want my DMF to last and putting much more power through it will make it give up faster, im sure.

Its hard for me to describ it in words exactly what my clutch or combination with throttle is like but it is not right as both my 2 year old works van and Wife's 5 year old Mazda are much smoother.

With both of these you can select 1st lift your clutch foot without throttle and they will pull away smoothly but the VTR was really bad before the tuning box was fitted and required 1300 + on the throttle and would still pull away as if it wanted to stall etc

Wish you were closer to me so you could sample it.
Its much improved now so it can't be that bad and i have felt no slippage
as yet..

Our previous C5 estate was having running problems, the Citroën indy fitted a new MAF sensor just before we bought the car from them, but it was not a genuine Citroën part. The car felt slow and to eliminate things i swapped the MAF with the one from my C5 which made the estate drive much better, much more like it should have been. So we got a new one from Citroën for it, i think it was around £100.

Thanks for giving me a dealers price for the MAF I can compare with
I see they sell after market ones for around £40 and have seen originals
on ebay for around £70.
It will have to be brought from the local official Citroen dealer for peace of mind and to know its really an official one!

My car averages 40.9MPG on my trip computer most of the time with my daily driving, which is a right mixture, town, motorway, B roads and heavy city centre traffic, usually without sparing the limited horses! I find my trip computer under reads by around 3-4MPG on what i actually calculate, so it really does 43-44MPG on average. On a run it will do 50MPG without too much problem, sitting at 70-80... Im impressed with the MPG.

Well my MPG is definately similar to what you are getting, I think it has improved a few MPG since putting the Synergy tuning box on and has actually made my trip computer more accurate as reads 1 mpg lower than it's actually doing and before it was reading 1mpg more!

Ive no idea what mine would do 30-50, im never in 5th by that point. Though i guess i could have a try and see what it does! 5th at 30 is about tickover, 1000rpm.

Time to get that stopwatch out on a closed off private road

I doubt there is a problem with it, though it might be worth getting it on a Lexia to see if there are any codes come up. Its very interesting to see how a Lexia actually works and what it can do, im thinking of getting one.

Im still thinking about a remap, thats the route i want to go if i do decide to improve performance, which would be nice.

I do hope to get my car on a Lexia sometime in the near (6 month) future
just to see what its all about and make sure all is as it should be

I also hope you do get a remap done as haven't seen any real-life user info from anyone so far on it but what i have read is that the tuning boxes are better for lower down torque which seems to have been proven in many reviews.

And really how often do we take the revs in our diesels above 3,000 rpm
in normal driving?
My change gear point is usually around 2,000 rpm in most gears other than 1st.

[Citroenmad]

Well, my limited experiences of remapped diesels is a bit different to how you mention. Ive not heard many cars produce more power/torque above 3000 and hardly any improvement low down in the range.

Usually torque is improved low down and it makes the engine more drivable without the need to work it quite as hard. We used to have a 2.5TDi VW which we had remapped, after the map the engine ran and sounded much smoother, there was less smoke and the drive was transformed. This was not a generic remap, the ECU file was downloaded and the file was changed to produce the best remap to suit that vehicle. As opposed to downloading a generic file onto the ECU which works differently in every car, as no car is the same. The power increase was very noticeable throughout the rev range.

Ive driven another VW with a remap, this is similar to the above but it was put on a rolling road and had a custom remap. Again the increase in power is spread over the rev range, however i would say more of the increased power is low down ad it does run out of performance about 3500. Both this VW and our 2.5 experienced increased MPG after the remap!

Its true, there is rarely reason to rev a diesel above 3000rpm. The HDI is higher revving than most other diesels ive driven, as it can rev to around 4500, maybe slightly more, though reving it to this is pointless and the pull has long gone.

If i got my C5 remapped and found that the extra performance was all top end id not be too happy with the results. Im wanting more grunt all of the time, which im hoping a remap will give.

Id be happy with a remap and nothing else, as i dont think a C5 really justifies trying to get the most out of its engine. Its a cruiser and as standard it provides ample pull, but a bit extra go would not go amiss, i agree.

Its something im considering, but it will probably take me ages to get around to doing that, as there are things i want to do with it first.

Mine is on 78K miles now and the clutch seems fine, sometimes there is a slight judder if pulling away on a very steep hill but nothing noticeable. Its having a problem with the gearbox, sometimes it crunches during changes into 2nd or 4th, however ive to used to this and with careful changes it doesn't. It seems as if the syncromesh is weak but im yet to get to the gearbox specialists to see what they recommend. Ive stopped noticing it now as ive got used to changing gear slowly to avoid a crunch.

Ive not heard of any problems with this gearbox, so im not sure why mine is playing up. Maybe its something to do with the hydraulic clutch might need bleeding - i need to do that anyway. The last owner swapped it for an automatic Golf, so maybe they were not good with gearboxes! So that needs looking at before a remap.

Ive no doubt that apart from that the car can cope with a bit of extra power, a normal remap is not going to put much stress though the running gear. Our 2.0 16v HDi C5 is a very nice engine, its smoother than the 8v, the pull is very strong and it has very good torque through the rev range and it pulls well low down. Its 6 speed box makes it a great cruiser, 70 at 2000rpm makes it an even more refined drive than the 8v and economy, if anything, is actually better.

I would like to swap mine for a facelifted C5, probably with the 2.0 16v HDi 138 engine, as i do find that very good to drive. However the latrer engines bring more complications and ive heard some reports that they are not as strong as the 8vs. They all have a FAP filter, and while this is less of a hassle on the later engines than it is on the earl 2.2 136, its still there.

Our 16v is used for transporting heavy boxes of oil products around the NorthEast, it does quite a few miles and its always loaded down. The economy is always around 45MPG despite carrying the weight (which is better than my 8V) though it is driven slower! Its not had any problems as yet, its now on 61K miles and its the best drive of the 3 we have. It does eat through tyres, the rears have lasted only 16K miles, despite running them at their upper pressure - i guess its the weight.

Now, a 2.0HDi 16v with a remap would be a very nice car, giving it a very achievable 165-170+ BHP, with similar MPG.

Though ive decided to keep my 8v for a while yet, id like a facelifted C5 but after getting the issues sorted with this one i feel i should get my use from it now and just run it. I could just buy another C5 and have problems with that one. So ive decided, for now atleast, that the one i know is best.

I imagine some people this this will be odd, but i really enjoy driving my C5 and look forward to going anywhere in it, the longer the journey the better.

[timborob]

Well, my limited experiences of remapped diesels is a bit different to how you mention. Ive not heard many cars produce more power/torque above 3000 and hardly any improvement low down in the range.

Usually torque is improved low down and it makes the engine more drivable without the need to work it quite as hard. We used to have a 2.5TDi VW which we had remapped, after the map the engine ran and sounded much smoother, there was less smoke and the drive was transformed. This was not a generic remap, the ECU file was downloaded and the file was changed to produce the best remap to suit that vehicle. As opposed to downloading a generic file onto the ECU which works differently in every car, as no car is the same. The power increase was very noticeable throughout the rev range.

Ive driven another VW with a remap, this is similar to the above but it was put on a rolling road and had a custom remap. Again the increase in power is spread over the rev range, however i would say more of the increased power is low down ad it does run out of performance about 3500. Both this VW and our 2.5 experienced increased MPG after the remap!

Its true, there is rarely reason to rev a diesel above 3000rpm. The HDI is higher revving than most other diesels ive driven, as it can rev to around 4500, maybe slightly more, though reving it to this is pointless and the pull has long gone.

If i got my C5 remapped and found that the extra performance was all top end id not be too happy with the results. Im wanting more grunt all of the time, which im hoping a remap will give.

Id be happy with a remap and nothing else, as i dont think a C5 really justifies trying to get the most out of its engine. Its a cruiser and as standard it provides ample pull, but a bit extra go would not go amiss, i agree.

Its something im considering, but it will probably take me ages to get around to doing that, as there are things i want to do with it first.

Mine is on 78K miles now and the clutch seems fine, sometimes there is a slight judder if pulling away on a very steep hill but nothing noticeable. Its having a problem with the gearbox, sometimes it crunches during changes into 2nd or 4th, however ive to used to this and with careful changes it doesn't. It seems as if the syncromesh is weak but im yet to get to the gearbox specialists to see what they recommend. Ive stopped noticing it now as ive got used to changing gear slowly to avoid a crunch.

Ive not heard of any problems with this gearbox, so im not sure why mine is playing up. Maybe its something to do with the hydraulic clutch might need bleeding - i need to do that anyway. The last owner swapped it for an automatic Golf, so maybe they were not good with gearboxes! So that needs looking at before a remap.

Ive no doubt that apart from that the car can cope with a bit of extra power, a normal remap is not going to put much stress though the running gear. Our 2.0 16v HDi C5 is a very nice engine, its smoother than the 8v, the pull is very strong and it has very good torque through the rev range and it pulls well low down. Its 6 speed box makes it a great cruiser, 70 at 2000rpm makes it an even more refined drive than the 8v and economy, if anything, is actually better.

I would like to swap mine for a facelifted C5, probably with the 2.0 16v HDi 138 engine, as i do find that very good to drive. However the latrer engines bring more complications and ive heard some reports that they are not as strong as the 8vs. They all have a FAP filter, and while this is less of a hassle on the later engines than it is on the earl 2.2 136, its still there.

Our 16v is used for transporting heavy boxes of oil products around the NorthEast, it does quite a few miles and its always loaded down. The economy is always around 45MPG despite carrying the weight (which is better than my 8V) though it is driven slower! Its not had any problems as yet, its now on 61K miles and its the best drive of the 3 we have. It does eat through tyres, the rears have lasted only 16K miles, despite running them at their upper pressure - i guess its the weight.

Now, a 2.0HDi 16v with a remap would be a very nice car, giving it a very achievable 165-170+ BHP, with similar MPG.

Though ive decided to keep my 8v for a while yet, id like a facelifted C5 but after getting the issues sorted with this one i feel i should get my use from it now and just run it. I could just buy another C5 and have problems with that one. So ive decided, for now atleast, that the one i know is best.

I imagine some people this this will be odd, but i really enjoy driving my C5 and look forward to going anywhere in it, the longer the journey the better.

Hi Chris

I just tried replying to you but lost all of my text as timed out
Arrrgh!


It sounds like you have alot of practical experience on remapping so I would go for one if you can afford it.

I chose the tuning box path as read it worked and went to the right maker which has worked for me.

main advice to anyone else reading is to only use verified dealers or you could end up with a non running car.

My cars now covered 107K and my gearbox seems fine and no missed or crunched gears, as you say more important to get that checked before a remap.

I too would like a 16v C5 and this will probably be my choice after this one in around 3-4 years time.