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jay s
09-03-2008, 13:05
this is starting to **** me off now, every time ive been to rr in the last 2 years the car has run lean. went to one yesterday and the same shit happened. Now i last had the car remapped a month ago at hillpower due to it running lean topend. at the time it was done everything looked good now month later its ****ed again :? im not gonna blame the map on the car as imo its kinda obvious that something else must be **** and the map just reverts back to how it was before. can anyone try and list a few problems that would make it run lean. fuelpump is an upgraded pump with about 30k on it but its had a hard life... filter isnt too old...
ill post a graph of my results yesterday and as you can see it made 160bhp @ 6k 138lb/ft torque, but in the words of the man doing the rr " power just hits a brick wall at 6k and stops dead " he also said if it had runs it course it would of hit 175-180bhp but just hasnt got the fuel to give, need to get this sorted once and for all
http://i10.photobucket.com/albums/a117/jay16v-/scan0001-1.jpg
http://i10.photobucket.com/albums/a117/jay16v-/scan0002-2.jpg
http://i10.photobucket.com/albums/a117/jay16v-/surryrrday002.jpg

stan
09-03-2008, 13:13
Do you have power-run graph with a fuelling curve on it from when nick mapped it?

This has been on ongoing problem for some time now?

jay s
09-03-2008, 13:38
only graph ive got with a fuel line is from when it was done again in june 06 havent got one from last time but it looks the same as the one below.

http://i10.photobucket.com/albums/a117/jay16v-/scan0004.jpg

matty w
09-03-2008, 14:02
probably nothing to do with it but is it worth getting the injectors refurbed

1fast6
09-03-2008, 14:20
How reliable is that rolling road though?

For instance, look at the torque curve in the second pic. it's all over the place!

northy
09-03-2008, 14:21
get it back to nicks for a run on his dyno...im sure if its a reoccuring prob then he will fix it

midge
09-03-2008, 14:42
jays injectors where re-furbed when his engine went in a couple of years ago, he also has nicks upgrade fuel pump..

torque curve in second pic ?

jay s
09-03-2008, 14:54
yeah i was gonna say that about the second pic, its the fuel line not torque, its shoots up at 5.5k meaning its running lean. its meant to be smooth to an extent... ill give nick a ring tomorrow and see what he says about it. as i said tho i dont think its the map causing it to run lean.....

titcharoony
09-03-2008, 16:42
when u get ur car rolling roaded, do they drive it in and do everything for u?

midge
09-03-2008, 21:20
yep

Robertio
09-03-2008, 22:17
Not Clio specific, but on cars I've mapped seeing that would indicate fuel pump. I'd suggest running a power feed stright from the battery and seeing if the pump will do it's job, could be old wiring causing problems. Common fault on jap stuff, and something I've got to do on the RX in the next few days.

Assuming the pump is doing it's job then it is over to the fuel pressure regulator and map/maf sensor. If the map sensor is not sending out the right voltage then the ECU will look in a different cell in the fuel map, giving the wrong fueling. If the FPR hose is loose then it may be air is escaping after a certain point, so it is reading the wrong air pressure and not increasing fuel pressure accordingly.

You've also got the possibilty of a fuel leak at the o-ring on one of the injectors, or any number of annoying little possible causes. I'd start with the first 3 parts though, if you have another Clio owner locally you can always borrow any appropriate bits and give it a try. If you were up here we could have taken bits off my car, stuck my wideband in the exhaust and looked at it for you, but it is a bit far to travel ;)

stan
10-03-2008, 14:23
as above theres numerous things which could caus it. The only way to eliminate them is to have fuelling feedback, and check them...so really you want to ask nick to investigate it on the dyno, though this may be quite costly.

if its nothing mechanical, then perhaps its an issue with the coding in the ecu. perhaps its related to the "issue" people were having with hillpower chips, where disconeccting the battery for a short while was yielding better performance.

eternalife
10-03-2008, 15:14
as above theres numerous things which could caus it. The only way to eliminate them is to have fuelling feedback, and check them...so really you want to ask nick to investigate it on the dyno, though this may be quite costly.

if its nothing mechanical, then perhaps its an issue with the coding in the ecu. perhaps its related to the "issue" people were having with hillpower chips, where disconeccting the battery for a short while was yielding better performance.

Is this related to ECU 'learning' by which a reset goes back to the base map?
Also, is it preferable to reset the ECU when the car is warm?

stan
10-03-2008, 15:18
yes, when reset it loses parameters it has learnt.

as for when warm....logic would say do it from cold, so it has a full range of conditions to run through.

jay s
10-03-2008, 17:25
right just spoken to nick and he said pump should be fine as its a high flow item and has only done 30k which he says is nothing for it, he suggested i change the fuel pressure regulator as it may be sticking... its never been changed and is the same one that was on my 1.8 4 years back so proberly past its best, ill see if midge has a spare i could try.......

stan
10-03-2008, 18:05
cant see it being the fuel pressure reg personally, but worth a try to set your mind at rest.

might be an idea to remove the injectors and check O ring condition. replace if necessary, or refit with a bit of red grease if they are ok.
but again i think this is clutching at straws.

the way the fuelling is being cut is very sudden and definate. its not gradual, or uneven.
personally i think its more of an ecu related issue.

midge
10-03-2008, 20:25
i do have a couple of spares mate, thier not new though, and if we change it we wouldnt know if its fixed!?

jay s
15-03-2008, 22:02
right went round midges today and tried one of his spare regulators, this has seemed to make the problem worse. i can now actully feel the car holding back real bad at 6.5k ( really doesnt like to rev, kinda stops but moves very slow if you get what i mean ) midge noticed this himself after we fitted it. i drove home with it on thinking it may iron itselfout but has'nt. gonna fit my one tomorrow and hope it goes back to how it was as it atleast pulled smoothly to the end unlike now :?

eternalife
15-03-2008, 22:13
Did you try resetting the ECU?

cliolord
16-03-2008, 00:15
Bit of a blast into space but what about fitting a complete F7R fuel rail & injectors? I had a problem with making power past 6K and pinking issues, this was down to an injector issue, dirt or something was effecting fuel atomisation. Got injectors flow tested and cleans and blasted the rail and it solved it

matty w
16-03-2008, 17:31
i wonder if its worth trying a gauge to see how much fuel pressure there is,have you got a fse regulator on your car jay?

jay s
17-03-2008, 17:33
yeah been looking at a fuel pressure gauge but am having hassel finding an electrical gauge to go inside the car. can get a mech gauge but will need an isolator aswell which pushes the price up. am deff gonna get a lumination afrm as it will be handy trying to sort this problem plus ill want one when it is sorted just to keep check. on another note car now seems to be behaving itself and seems to drive normal once again :roll:

wazza16v
17-03-2008, 21:10
Alright Jay did you manage to sort the car out? Ive been meaning to come up and see you but ive been so busy with work/uni.