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Engine Specific Info and Questions => IDI Engine => Topic started by: dieselsmoke on August 19, 2008, 10:39:10 am

Title: pump timing
Post by: dieselsmoke on August 19, 2008, 10:39:10 am

I was looking in the manual and it says for the 93-96 1.9 AAZ turbo pump timing that it should be .80. Why is it so low for these newer pumps as compared to the old pumps. I heard someone say that you can still set these to 1.00 -1.05, is this true? Will this effect anything on these pumps? If I do set it higher which would I want it at 1.00 or 1.05? Thanks

Title: pump timing
Post by: burnt_servo on August 19, 2008, 11:12:07 am

isn't the injector pop presure slightly lower than the 155 bar used on the older engines ?

Title: pump timing
Post by: blkboostedtruck on August 19, 2008, 11:45:28 am

AAZ injectors are 150bar on the dual stage injectors that i've seen!
but i don't know what the key setting is?
someone will chime in on that setting?
Duane

Title: pump timing
Post by: dieselsmoke on August 19, 2008, 02:21:16 pm

For the dual stage injectors the first stage is supposed to be 155 bar which is what mine are set too. I don't know what the second stage is but I know that you need some special equipment to test it. I am just curious about the pump timing. Going from .80 to 1.00 or 1.05 is alot.

Title: pump timing
Post by: jimfoo on August 19, 2008, 05:19:13 pm

I was running mine at 1.0mm.

Title: pump timing
Post by: jtanguay on August 19, 2008, 05:29:38 pm

lower timing = less NOx.  increase timing = higher NOx.  probably the single reason for the lower timing.  increase it to about .90 or even 1.00 and enjoy increased power and possibly mileage?  lower timing also gives a quieter running engine and a bit more torque.

Title: pump timing
Post by: Smokey Eddy on August 19, 2008, 06:48:36 pm

VERY interesting....

Title: pump timing
Post by: dieselsmoke on August 20, 2008, 09:05:39 am

If I turn it up to .95 or 1.0 mm will I get smoke coming out of the exhaust or should I be ok?

Title: pump timing
Post by: jtanguay on August 20, 2008, 09:09:56 am

Quote from: "dieselsmoke"

If I turn it up to .95 or 1.0 mm will I get smoke coming out of the exhaust or should I be ok?

if you do its because something is wrong inside the engine  :lol: or you turned up your fueling too high.

ideally though you want the .80 timing for idle only, and as soon as you hit the accelerator you want the increased timing.  not only does it consume a bit less fuel, but it also gives you a nice quiet idle  :wink: some AAZ pumps have a solenoid that retards the timing... that in conjunction with an idle switch (to activate the timing retard device) on the pump could give you that  :)

Title: pump timing
Post by: dieselsmoke on August 20, 2008, 02:03:14 pm

Will the car still idle ok if I advance it to .95 or 1.0 mm or is it going to idle rougher? Does this effect anything for cold weather like when it goes down to -35 celcius in the winter time?

Title: pump timing
Post by: jtanguay on August 20, 2008, 02:11:09 pm

actually cold starting is better with increased timing... it will get louder though thats for sure  :lol:

Title: pump timing
Post by: bert on August 20, 2008, 02:18:15 pm

my AAZ is set at 0.95 and the cold starts are loads better,i dont use the cold start anymore  :wink:  and the power is amazing

(http://i78.photobucket.com/albums/j95/citigolf_2006/scan0001.jpg)

Bert