Help with cammed 172

[chrisc172]

I've just taken a bit of a gamble on a cheap 172, got it off a lad that bought it cammed. problem i have with it is it runs lumpy as hell at idle and under about 3k. doesnt like 3/4 throttle, just likes full throttle, flies at full throttle but there is a little delay before it takes off. but trying to drive it slow it judders like mad.

What i want to know is can this be sorted with a live map, even if just the slow running could be sorted not that bothered with the idle, its not too bad on idle when its warm anyway. Sorry dont know what cams are in it as i bought it like this, got the original cams anywhay if it cant be sorted but would like it get it running as it is.

Any help would be great thanks.

 

[DMS]

I'm not an expert on these things, but it sounds like the cams have just been replaced and the ECU left with the standard map.
If you could find out exactly what cams they are we'd probably be able to offer more help.
If it is a mapping issue, I'd bet that getting it live mapped would free up some power too.

 

[RSTuning]

You could do with it checking to see what it's doing, it's likely that the fuelling is way out or the cam timing...

 

[chrisc172]

The lad said it had the ecu replaced so its never been mapped for it, thats wat made me think if i get it and then live map it hopefully it will sort it out.
Think theres power it be had from mapping it cos it decatted and got the 182 manifold on it. Just want to if it worth the trip to leeds.

 

[DMS]

It'd probably be worth the trip just to find out what's wrong with it.
Where do you live? There are a few specialists dotted all over the country so there may be someone closer?

 

[chrisc172]

Well it will be coming to you for the mapping if it does get done. it does feel like the fuelling is out when i boot it cos of the delay and it sounds like a 2 stroke thats getting too much fuel then it just takes off ha.

 

[chrisc172]

live near durham mate

 

[Bazzon]

If you live in the South Tour-De-force, if you live north RStuning

 

[chrisc172]

Apprently its been to renault and they said all was ok apart from the mapping but they cant do nothing with the map. Can this run ok with the standard ecu or will a stand alone ecu be needed?

 

[DMS]

If you already have an aftermarket ECU you'll be better sticking with that IMO.
Someone correct me if I'm wrong, but I think there are certain cam profiles that the standard ECU can't cope with.

 

[chrisc172]

It only has the standard ecu, its just been replaced so he knows its not been mapped. Im just hoping its not a cam profile that the ecu cant cope with as i cant afford a aftermarket ecu. Can anyone have a guess from what ive disgribed if the standard ecu will be ok to run these cams.

 

[GodSpeed]

It only has the standard ecu, its just been replaced so he knows its not been mapped. Im just hoping its not a cam profile that the ecu cant cope with as i cant afford a aftermarket ecu. Can anyone have a guess from what ive disgribed if the standard ecu will be ok to run these cams.

Map the car!!

If its never mapped for the cams its a fair chance that its running lean on top revs. That is very bad and may cost a blown engine if you are unlucky. Take my advise and get it mapped right away!

I have only good things to say about Henk at www.fastchip.nl dont know if he's got time for custom calibrations atm.

Apprently its been to renault and they said all was ok

And as some one said before check that the timing is spot on before you map otherwise it will be a waste of money. Since it is a bit of a hazzle to check the timing I would not be to sure they actualy did this. Make sure they did or take it to someone who can check that and map it at the same time.

 

[chrisc172]

Looks like its RS Tuning then, anyone knows roughly the cost of mapping to suit cams?

 

[Fred@BTM]

£400 approx for a custom map, i'd check the cam timing before you do anything, is it a phs1 or 2?

 

[drhowser]

the most important thing to find out is which cams are in the car.
i think that if there is any overlap in the timing the standard ecu will struggle to cope.

like fred says, have the timing checked too.

as for cost, give paul a call at rs tuning, he'll sort you out.

 

[chrisc172]

its a ph2, how can i find out what cams are in the car? can any garage check the timing or do i need to find a pretty good one?

 

[drhowser]

can you get in touch with the previous owner or do you know where the cams were fitted?
the only reason i'm saying that is that a lot of cams will only run correctly on standalone management.

i've no idea at all about how to chect the timing though.....

 

[Fred@BTM]

needs a renault specialist to check the timing (dealer if you must, but i would suggest using a specialist!)

 

[chrisc172]

well the owner i got the car off put the engine in from a 182 and it was cammed but didnt use the 182 ecu, then ended up buying a new ecu so cant trace who fitted the cams.
But its a new ecu so was never mapped for the cams, but dont think the car he got the engine from had a standalone ecu. so its possable it just needs mapping.

 

[Fred@BTM]

possible, IMO its either got proper lairy cams or the timing is out

a lot of cams when timed up properly idle fine you see

 

[chrisc172]

he did say renault did everything to do with all the timing and that but just put it down to needing mapping to suit, but thats if wat he's saying is rite.

 

[chrisc172]

possible

knew it didnt look right just couldnt think why ha

 

[drhowser]

i might be wrong, but i'd be suprised if a renault dealer agreed to time up aftermarket cams, have you got any paperwork to do with that?

what kind of mpg have you been getting from it?

 

[chrisc172]

got all the paper work for the ecu and labour but dont say nothing about timing. he says the lad wat works theres his mate so he was working on it for him.
Not drove it much but it only got about 23mpg, but that wasnt driving it slow mind.

 

[Andyman]

i might be wrong, but i'd be suprised if a renault dealer agreed to time up aftermarket cams, have you got any paperwork to do with that?

what kind of mpg have you been getting from it?

Yeah they do but they only time to stock Renault spec. My local one even offered to mod the pistons via the local machine place if needed lol :approve:



OP, From what youve said sounds like the map was just ecu based but RR'd test will give you a all round better idea mate

 

[sideways danny]

idling high sounds a lot like there's an airleak