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Engine Specific Info and Questions => IDI Engine => Topic started by: TITan on October 21, 2015, 08:42:29 am
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Bit of a backstory:
The engine: AAZ with Garrett T2 turbo, boost controller set to ~1.1 bar/16 psi, governor mod, modded boost pin, 2.5" downpipe. 1.0mm timing
The car ran perfectly for about half a year (still a bit lower on power compared to my old SB 1.6 TD @ 1.2 bar, but the lowdown torque was better) then the IP sprung a leak from the distributor head. Didn't have time to fix it right away so the leak got worse and worse. At the same time the max boost started falling to factory levels (0.75 bar). Than to top it off the cooling system started acting strange (dead thermo switch plus the thermostat started sticking)
Flushed the coolant, changed the switch and thermostat - no more overheating. Changed the oring - installed the pump head 180 deg out, took a bit of time to figure that out :D . No more leaking IP ;D But also no more power :-\ The engine struggled to rev past 3500 RPM (in the begining it puled strongly to 5000), boost was down at 0.5 bar.
Things I have tried since:
Changed the fuel filter - no change
Checked the turbo by hand - no excessive play. It's already spinning at idle.
Swapped in the pump from my old SB 1.6TD - changed the characteristics of the engine, but not much better.
Since I have a different flywheel I checked the timing marks by dropping a valve. They were a bit off, but not by much. Rechecked the timing on both pumps atleast three times.
Removed the rest of the (quite restrictive) exhaust. - a bit better, but not much change.
Cleaned/tried removing the cone air filter - different sound, not much change of performance.
Removed the line to my wastegate so it doesn't open - still almost no boost.
Tried running the pump directly from a can of diesel and ATF to clean it out - no better
Adjusted internal pressure - not much change.
Played around with the pump settings - a bit better, but can't get it to run properly
Cleaned the wastegate and rechecked that it was moving freely (it was stuck when i got the engine) - boost is a bit better, but not by much.
Could always get a bit of black smoke.
After fiddling around with the pump settings it pulls to about 4000 RPM and boosts to 0.7 bar/10 PSI withouth the wastegate.
Other than that, the engine runs perfectly. The temperatures here are just above freezing right now and it starts up right away. No white smoke at all. From time to time a bit of blue smoke right at startup, but nothing drastic. Idles nicely, quite responsive lower down the rev range, max power is from 2000 to 2500 RPM right now.
I really don't know what to try next. Lift pump maybe?
Pic for attention:
(http://i602.photobucket.com/albums/tt104/worthersee/T3/01E/IMG_20140724_195100_zpsa5605074.jpg)
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Compression? Injectors?
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Haven't tested either.
But from how nicely it starts I'm guessing the compression is ok.
Have to make a adapter for checking compression on a diesel and find somebody with/make my own pop-tester.
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What exactly are you looking for?
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have you visually checked that the wastegate is working and not stuck open?
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Are you 100% sure your cam to crank timing is perfect? The compression test could help rule that one out
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have you visually checked that the wastegate is working and not stuck open?
Wastegate is working, and is making a good seal. No cracks wisible on the pedal or turbo housing.
Are you 100% sure your cam to crank timing is perfect? The compression test could help rule that one out
Double checked that my flywheel marking was spot on TDC via dropping the valve and looking at when the nr 1 cylinder made contact in both directions, than used the center from that. Reset the timing 10 times probably.
Compression test will be done as soon as possible. Same with poptesting the injectors (maybe trying some GTD injectors in the meantime).
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Flushed the coolant, changed the switch and thermostat - no more overheating. Changed the oring - installed the pump head 180 deg out, took a bit of time to figure that out :D . No more leaking IP ;D But also no more power :-\ The engine struggled to rev past 3500 RPM (in the begining it puled strongly to 5000), boost was down at 0.5 bar.
sounds like when you 'fixed' pump you now may have a air leak, or have reinstalled pump head wrong