I've just put on a boost meter and found out my max boost is only 0.8bar, about 11.5psi. Mine is a 96 Xantia 1.9TD. For those who have installed a boost meter, what is your standard boost?
So far I have modified the boost compensator fuelling on top of the fuel pump. Loosened the 13mm nut, then 2 full turns clockwise on the T27 screw. Some websites recommend turning anti-clockwise but after turning clockwise, I feel more response in the lower gears. Can anyone confirm this? 2 of my friends did it, one complained of more smoke, the other complained of increased fuel consumption around town.
Next is the max fuel settings and KKK turbo wastegate tweak. Any advise from those who've done it?
1.9TD turbo boost
Moderator: RichardW
1.9TD turbo boost
Xantia 1.9TD 1996
There are two parts to the fuelling adjustment. The screw on the top (that you have adjusted) gives more fuel (screwed in) throughout the range. This is why you have noticed a better response at low speed.
The main change in fuelling on boost is adjusted inside the top of the device. When you have altered this for more fuel on boost you'll find that you do actually have to adjust the top screw the other way - to reduce smoking.
Do a search on here for "turbo boost adjust" (search all terms) and you'll get some light reading.
The main change in fuelling on boost is adjusted inside the top of the device. When you have altered this for more fuel on boost you'll find that you do actually have to adjust the top screw the other way - to reduce smoking.
Do a search on here for "turbo boost adjust" (search all terms) and you'll get some light reading.
Pug Rifter long (20) - 41mpg - Gutsy for a 1.5!
Xantia 1.9 TD Temp.2 Break (97) - 208K@42mpg - Resting again.
Berlingo Multispace 1.6 16v (51) - 184K@36mpg - My shed! Still runs 15° retarded...
Xantia 1.9 TD Temp.2 Break (97) - 208K@42mpg - Resting again.
Berlingo Multispace 1.6 16v (51) - 184K@36mpg - My shed! Still runs 15° retarded...
Hi John, I've done a fair bit of tweaking with my old 93 tdsx following advice from different websites, and I think the best advice I can pass on is to leave the tweaking to people that know what they are up to . If you must have a go, then be sure to remember the original settings ( I messed about so much that it has taken me ages to get the car running as it was !! -In my case it was definitely a little knowledge proving dangerous) I really wish I had left it alone, or spent the money and had it tweaked by derv doctor..
I won't do that again
john
i have tweaked my zx td extensivly you might find the following of help / interesting:
Boost compensator valve:
you have wound the torx screw down, this provides the engine with more fuel throughout the range but the biggest increases are gained when your remove the alloy top of the compensator valve. Remove the diapragm and spring beneath and wind the spring base down (clockwise) three turns. Then put the diapragm back in with the accentric taper on the bottom of the pin to the right (allowing the "reader pin" inside of the pump on the left to perotrude further.)
Max Fueling:
A screw on the right hand side of the pump deals with the off boost fueling. Winding this in (clockwise) increases the amount of fue supplied. You can do this up until the point wherethe idle of the engine will start to rise. Combat this by turning the idle down by adjusting the throttle lever.
Boost:
Ive got the garett turbo so its not the same as yours but the pressure on these is increased by shortening the wastegate actuator arm. My zx is running 20psi when at full load.
You should bear in mind that playing with these engines is pretty much asking for head gasket failure. _ mine failed after 18 months but it turned out that the lumypy running on start up that the car suffered from in the first two years i had it was cuased b y a leaking head gasket and so it managed 18 months on a gasket that was leaking slightly causing low compression on no 4 causing the engine to smoke.
The car now has a steel laminated gasket fitted so it shouldnt go again.......
Its a question of getting the ballance between all of the above adjustments right to avoid smoke etc and i have found that fuel consumption is not much worse when driving sensibly.
i have tweaked my zx td extensivly you might find the following of help / interesting:
Boost compensator valve:
you have wound the torx screw down, this provides the engine with more fuel throughout the range but the biggest increases are gained when your remove the alloy top of the compensator valve. Remove the diapragm and spring beneath and wind the spring base down (clockwise) three turns. Then put the diapragm back in with the accentric taper on the bottom of the pin to the right (allowing the "reader pin" inside of the pump on the left to perotrude further.)
Max Fueling:
A screw on the right hand side of the pump deals with the off boost fueling. Winding this in (clockwise) increases the amount of fue supplied. You can do this up until the point wherethe idle of the engine will start to rise. Combat this by turning the idle down by adjusting the throttle lever.
Boost:
Ive got the garett turbo so its not the same as yours but the pressure on these is increased by shortening the wastegate actuator arm. My zx is running 20psi when at full load.
You should bear in mind that playing with these engines is pretty much asking for head gasket failure. _ mine failed after 18 months but it turned out that the lumypy running on start up that the car suffered from in the first two years i had it was cuased b y a leaking head gasket and so it managed 18 months on a gasket that was leaking slightly causing low compression on no 4 causing the engine to smoke.
The car now has a steel laminated gasket fitted so it shouldnt go again.......
Its a question of getting the ballance between all of the above adjustments right to avoid smoke etc and i have found that fuel consumption is not much worse when driving sensibly.
Zxtd Aura converted from 1.8i Petrol - Lowered, 20psi boost extra fuel - weeeeeee!
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")
Thanks for your replies. I've tweaked the max fuel screw about 40 degrees and its given better power. Idle is up from 850 to 900 rpm. Unfortunately my KKK turbo doesn't seem to respond to tweaking. I've done 4 full turns clockwise but it seem to only rise 0.05 bar or 1psi. I've maxed the turns now, only 5 turns in total but haven't test the boost yet. I don't think its going much anywhere. The turbo specialist said if the spring is weak, then there will be no increase in boost.
I had made the mistake of sending the turbo for servicing and modifying a few months back. I've had the spool changed to a bigger one but seems the low end torque is lacking now. Big mistake! Now I've discovered its leaking oil from the cold side as I've taken out the oil breather tube from the air intake, so there shouldn't be any oil going into the engine. Another big mistake of sending for servicing as there wasn't any leak from the cold side previously! I've already had full overhaul for my engine, so I hope there won't be any blown gasket, no higher boost anyway. Perhaps have to send back the turbo to the specialist.
I had made the mistake of sending the turbo for servicing and modifying a few months back. I've had the spool changed to a bigger one but seems the low end torque is lacking now. Big mistake! Now I've discovered its leaking oil from the cold side as I've taken out the oil breather tube from the air intake, so there shouldn't be any oil going into the engine. Another big mistake of sending for servicing as there wasn't any leak from the cold side previously! I've already had full overhaul for my engine, so I hope there won't be any blown gasket, no higher boost anyway. Perhaps have to send back the turbo to the specialist.
Xantia 1.9TD 1996
hi
dont bother sending the turbo to a specialist - if you are goitng to take it off get a garret to go on in its place from your scrapy they are easy to adjust.
are you measuring the boost by just reving the engine in neutral????? if so thats wrong because the engine will only produce significant boost when it is in gear and under load.
have fun...
dont bother sending the turbo to a specialist - if you are goitng to take it off get a garret to go on in its place from your scrapy they are easy to adjust.
are you measuring the boost by just reving the engine in neutral????? if so thats wrong because the engine will only produce significant boost when it is in gear and under load.
have fun...
Zxtd Aura converted from 1.8i Petrol - Lowered, 20psi boost extra fuel - weeeeeee!
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")
You could install a bleed valve instead if you wanted, about £20 from places like www.armval.co.uk 
No, not in neutral. I measure usually by driving up a long and winding hill where I have to use lower gears to go up. Have tried to look for a garrett from scrappies but so far no luck.are you measuring the boost by just reving the engine in neutral????? if so thats wrong because the engine will only produce significant boost when it is in gear and under load.
Are bleed valves the same as dump valves? Heard they don't do much in TDs except produce the sound.
Xantia 1.9TD 1996
Yeah im afraid so. their US supplier is trying to screw them over so the price would either shoot up and thus put him out of business or he has to source them from elsewhere. Send him an email and say Kingpleb from the Coupe forum sent you there and your looking to use it for a Citroen
He didnt believe me when i told him that they could be used on them and people would actually want them as well for the price they are superb!
He didnt believe me when i told him that they could be used on them and people would actually want them as well for the price they are superb!
i havnt used a bleed valve myself becuase the turbo has responded well to tweeeeeeks 
but:
the way i understand them to work is as follows:
there is a pressure pipe running to the waste gate which so that when the pressure in this pipe climbs the waste gate will open at a pre-set pressure setting say 14psi. This vents the pressure into the exhaust and not into the engine bay and so you dont get the normal dump valve whhooosh.
The bleed vale goes into a tee piece in the above pipe and is effectivly a regulating valve so that you can "bleed off" the pressure in this actuator pipe and so trick the waste gate into thinking a lower boost pressure in there than actually is, and so it doesnt open allowing the pressure to climb still further. you can adjust the pressure by adjusting the bleed valve ie more bleed off means higher pressure supplied by turbo....
but i still think the best bet is to adjust the turbo..
but:
the way i understand them to work is as follows:
there is a pressure pipe running to the waste gate which so that when the pressure in this pipe climbs the waste gate will open at a pre-set pressure setting say 14psi. This vents the pressure into the exhaust and not into the engine bay and so you dont get the normal dump valve whhooosh.
The bleed vale goes into a tee piece in the above pipe and is effectivly a regulating valve so that you can "bleed off" the pressure in this actuator pipe and so trick the waste gate into thinking a lower boost pressure in there than actually is, and so it doesnt open allowing the pressure to climb still further. you can adjust the pressure by adjusting the bleed valve ie more bleed off means higher pressure supplied by turbo....
but i still think the best bet is to adjust the turbo..
Zxtd Aura converted from 1.8i Petrol - Lowered, 20psi boost extra fuel - weeeeeee!
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")
MK2 Cortina 1600e
Honda Acty Romahome - 545cc!! - (the "beast")