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Uprated Camshaft Idle And Start Up Questions

gangles1987

Member
not had my car long (21 turbo) I know a little bit of its history it had some minor headwork about 4 years ago had the head ported and polished different valve springs and a camshaft fitted I believe it was a piper fast road cam different exhaust and a recon turbo ever since then the idle has been lumpy and sometimes the revs dip when pulling up and occasionally it will cut out also sometimes its awkward to start takes probably 10 secs of cranking then will run lumpy .
I know when fitting a cam lumpy idle is unavoidable and im prepared to live with it but was just wondering if there was anything that I could do to make it better it also over fuels pretty badly most of the time can these ecus be mapped to accommodate the camshaft or does it have to be tweeked manually (set up) like most old fords of this era need to have done my cars a phase 1 if that makes any difference and does anyone know whos best to speak to about this type of engine and setting it up to run better with the few mods it has

cheers
 
The engine is not easily mappable, no. Unless you have a grand to throw at standalone.

Idle/Stall, you need to clean out the Idle Control Valve and adjust the butterfly stop.
 
where is the idle valve on these I had quick look but not sure what these ones look like im used to the stepper type I spose I will have to live with it then as I cant afford standalone lol
 
Look at the plenium ( the thing with the words TURBO written on it. Follow it forward and just under a boost pipe it lurks there. Fromw what I recall it has 3 pipes attached to it.
 
also another quick one ...... what is standard boost on one of these 8-10 psi?? my gauge seems to hold just under half on the boost gauge would that be standard or do I need to plumb in a proper gauge to find out I cant see a bleed valve either anywhere so assuming it could be running standard if it is then it goes well...... so would imagine another 5 psi extra wouldn't do too much harm :D
 
Std boost is the second mark before the red area on the dash gauge...as Lee says 13.2Psii if the amal valve is operating properly.

The Idle control valve is here, yours will be a little shorter and fatter as this one is a later model. Remove, fill with brake cleaner, shake, empty, repeat until it comes out clean. Then fill with WD40, shake, empty and refit. Then adjust the butterfly stop down half a turn.

IMG_0022 (2).jpg
 
cheers for that i will take a look this weekend at that iacv i will take a proper look at the boost gauge too im sure its running standard boost as i cant see a bleed valve and it doesnt boost anywhere near the red line . what does the amal valve do is it like a boost regulator ???? like on newer turbo cars
 
Yeah it's an ECU controlled bleed valve. Very clever for it's age, it regulates boost according to throttle position, and also limits boost when the engine temp is under 50 degrees centigrade, or the car is in first gear (unless it's a Quaddie, they removed 1st gear boost limit on those)
 
The Sierra cosworth uses exactly the same method to control boost. Electronic pulses and all that jazz..
Quoting myself from 21TOC

"Standard boost is 13.2psi, or 900mBar, but in the std setup the actuator is set to open at 8psi.
13.2 is attained by a pulsating solenoid valve, AKA the amal valve. It pulses at a constant frequency of 12 Hertz, so <time open>+<Time closed> equals <constant> but it varies time open and closed to make the adjustment. It basically acts as an electronic bleed valve....boost controller stylee. When you are in 1st gear (2wd only) or engine temp is below 50 centigrade it limits boost to actuator pressure, ie 8psi, otherwise it changes its pulse profile to bleed away pressure and allows 13.2psi.

On top of all that, it also controls pre throttle butterfly boost pressure according to how much throttle you have on. Its a brilliant innovation, half throttle=half boost, instead of a setup like my old ph1 with no amal valve which hit over a bar of boost at 1/3 throttle. Great for fuel saving and cruising, prolongs the life of the turbo as it doesnt work as hard as well.
All this though, is assuming its working correctly. Problems begin when its not, from boosting low (8psi) to massive overboost (BOOM!). The overboost problem is dangerous but Renault saw fit to add an overboost protection system. It cuts in around 18psi and it breaks a circuit and turns your engine off. Again assuming its working, and hasnt been f**ked with by some boost hungry little scally. DO NOT REMOVE IT. Take the time to adjust and reset it to the required level. "
 
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