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Author Topic: Definite tach solution for a, sorry, ANY diesel engine  (Read 13397 times)

Reply #15November 06, 2012, 02:17:05 pm

R.O.R-2.0

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #15 on: November 06, 2012, 02:17:05 pm »
i believe im going to play around with my setup a bit more today..

see if i cant get a tach reading from my cluster..

i know the cluster is good..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #16November 08, 2012, 04:37:02 pm

snakemaster

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #16 on: November 08, 2012, 04:37:02 pm »
i used the crank pickup on my 1z mtdi ,its in a gasser 2.5 t4 transporter ,but now a mtdi wired up the sencer power from pump sol, and run the wire from no 2 pin to the gas taco , and have my  aftermarket diesel taco on to the w T , to compare gass taco on idle, reads 900rpm and the W one reads 650rpm m van dose ldle low. and  gaser at 3000rpm W at 2000rpm , tryed a small capacitor in line from no 2 pin  then a bit biger one ,just the same , need some way to get the  frequency down . i am not in to  electronics things bobers, but some one may be able to shed some light on this .
Glenmorangie  single highland malt

Reply #17November 14, 2012, 06:57:14 pm

R.O.R-2.0

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #17 on: November 14, 2012, 06:57:14 pm »
you positive your diesel tach is accurate?

i would lean more towards the gasser tach being accurate...

if its raining too hard, the diesel tach is in-accurate, and thats not cool..

my old audi 5000TD, the tach would quit working whenever you hit a puddle in the road..

then the belt would dry, and the tach would come back to life..

92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #18November 14, 2012, 09:13:56 pm

libbydiesel

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #18 on: November 14, 2012, 09:13:56 pm »
The crank sensor on the AHU/1Z will give four pulses per rev.  The gasser 2.5 (5-cyl) tach will be looking for 2.5 ignition pulses per rev and thus the discrepancy.  A gas 4 cyl tach is looking for 2 pulses per rev.  I've been planning on using a flip-flop to cut the crank sensor output in half in order to drive a typical 4-cyl gasser tach. 

Reply #19November 14, 2012, 09:28:30 pm

bbob203

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #19 on: November 14, 2012, 09:28:30 pm »
The crank sensor on the AHU/1Z will give four pulses per rev.  The gasser 2.5 (5-cyl) tach will be looking for 2.5 ignition pulses per rev and thus the discrepancy.  A gas 4 cyl tach is looking for 2 pulses per rev.  I've been planning on using a flip-flop to cut the crank sensor output in half in order to drive a typical 4-cyl gasser tach. 

whats this flip flop you are talking about?
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Need a car transported a long distance? Pm me for details.

Reply #20November 14, 2012, 09:48:30 pm

libbydiesel

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #20 on: November 14, 2012, 09:48:30 pm »
It's one of the most basic logic circuits.

http://en.wikipedia.org/wiki/Flip-flop_%28electronics%29

Reply #21November 14, 2012, 10:45:33 pm

bbob203

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #21 on: November 14, 2012, 10:45:33 pm »
After reading some of that I short circuited. lol.. What would one use to implement a flip flop circuit to do what your describing to cut the 4 pulse signal into 2?
92 Passat wagon M-TDi
03 Jetta wagon TDi
VE Timing tools for rent
Need a car transported a long distance? Pm me for details.

Reply #22November 14, 2012, 11:09:51 pm

ORCoaster

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #22 on: November 14, 2012, 11:09:51 pm »
I've been planning on using a flip-flop to cut the crank sensor output in half in order to drive a typical 4-cyl gasser tach. 


Well it might be this type of flip flop. 

Reply #23December 23, 2012, 05:44:14 pm

snakemaster

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #23 on: December 23, 2012, 05:44:14 pm »
aaa some info there would this flip flop do http://www.ebay.co.uk/itm/FLIP-FLOP-D-TYPE-SMD-74LVC1G175-Part-SN74LVC1G175DBVT-/390460792223?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item5ae946dd9f

or can i buy a set up ready to go , we have maplines , and rs hear , no rado shack  :)
Glenmorangie  single highland malt

Reply #24December 25, 2012, 12:35:02 am

libbydiesel

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #24 on: December 25, 2012, 12:35:02 am »
I'm not particularly electronics savvy, but I think that would work wired correctly. 

Reply #25December 25, 2012, 02:15:49 pm

R.O.R-2.0

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Re: Definite tach solution for a, sorry, ANY diesel engine
« Reply #25 on: December 25, 2012, 02:15:49 pm »
anyone have any idea about modifying the stock mk2 tach to accept a signal from a mag pickup?
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.