Can you set timing using diag software?

[cosmic_splatter]

Fixkick,

Can you set the timing of a 16v engine using the diagnostic software? Or does jumpering the pins on the DTC freeze the reading the ecu will see?

thanks,
John

[fixkick]

the ECU only knows what the sensors tell it, if you time the cam or spark wrong , that is a lie to the ECU and it will (add to the lie.)
say you set the CMP to 10deg BTDC (5 say is correct). then the ECU advances by 15, that is 25, and is 5 degree's too much.

you set the static timing with the freeze jumper and the ECU advances from there. On new cars the sensors are PRESET non adjustable.
how ever this can tool, you might see advance, not get to near 40 degrees, one of many hints its in limp home mode (failsafe)

there are 32 parameters to see.
here they all are, as published by the 1995 FSM

http://www.fixkick.com/ECU/Tech1/full_scan2.html

its not much but , not being blind any more is amazing...
good luck !

[cosmic_splatter]

I guess what I'm asking is...

1. Can you jumper the DTC to freeze the timing.
2. Read the ECU via software to set it.
3. Set the distributor to 5 degrees.

In other words, can you do the timing without a timing light using the ecu computer interface?

You may have answered this in your response, but I'm not following the logic. If you freeze the timing via the plug, what does the ECU software show? It shouldn't be changing the timing. Does it just freeze it to zero and will not change if you move the distributor? Or, will it show you the timing changes as you move the distributor?

I guess I can jumper that plug and see what the software reads out. It just seemed to me that this would be a very accurate way to set the timing since the ecu should know exactly where the timing is on the engine. Unless what you are saying is that the ECU assumes the timing is 5 degrees and adjusts everything using this assumption. I guess I thought with all the sensors on the engine that it would know the timing, but I see that this maybe not true. It has to use the assumption that you set it properly.

[fixkick]

sure that is covered in the timing page.
the ECU bounces timing all over the place at idle.
why? because that is how it controls idle speed, fast, the ISC is slow, but not timing changes, they are INSTANT
this is a FEATURE, and saves fuel with lots of advance at idle.
the ECU has fixed timing tables, you cant change them. they are indexed by RPM and LOAD. FIXED in ROM solid at a rock. (but INDEXED)

the SOFTWARE (really shows that the ECU thinks Advance is, not where it really is, after all it trusts YOU 100% to do that Correctly. static timing.
the number is this ( it logs, static + what the ECU set it ) they ADD,
on your car it has a DIZZY, and you get to time it where ever you want and the ECU can not see what you did , EVER.
to stop the BOUNCING timing , you insert the timing freeze jumber, the bounce ends the ECU the HALTS LIVE dynamic timing ADVANCE.
then you set the static timiing, with a timing light. this works same on all cars, 87 to even my 2004, later there is no adjustments.

no the ECU will not show your changes, that be impossible since the timing is frozen.
think about the CMP. the ECU only sees that trigger, and has no idea at all when it really happened. not possible. ever.
lets use alegra to see why.

total timing = Fixed static timing + advance.
if you lie to fixed, total lies.
the fixed means its hard coded in memory, like 5 degrees.
the mech. must set the static timing with a timing light, or you are fibbing to the ECU.

your crank shaft has no CKP sensor, so the ECU can never ever know, 0 degrees TDC ever, Impoossible.
so can not see you move the dizzy, ever.
no frame of reference. that is called.

the other sensors all measure air /water temp and air mass flow, not timing of any kind.

no timing light no joy, 20 bucks at harbor freight, my first one was $300 when young.

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the interface is for seening total advance at speed and loads.
very handy that.
but can not timing the engine with that.
the new cars this is fixed. there is no dizzy
the CMP has adjustments in 2004.
but later, that ended with frozen CMP, no slots, it for ever and ever set to 10degr, or what ever.

if by magic the ECU knew static timing, it have no need for you to set it.
ever.
it does not.

[cosmic_splatter]

Fixkick,

Fantastic write up! That explains a lot of the pieces I wasn't putting together!

thanks!
John

[fixkick]

your welcome !!! happy hunting....

let me know when you get 180F?
and when a new 02 (with working heater) how fast closed loop hits from dead cold engine (sure it's longer in Siberia) but need bench mark for typical summer day.
the 1996 can do this in under 20 seconds.
the limit is not the year, not the 02 sensor (it heats same speed as the 96) it's pure firmware, in the ECU.. i find that interesting, these. facts.

closed loop fast saves fuel and prevents stress on the CAT too.

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a new stat will warm up much faster, it delays opening....

[cosmic_splatter]

Fixkick,

The saga continues. I replaced both the thermostat as well as the ecu water temp sensor, but it still climbs to 150 degrees and stops. I'm going to do some testing to be sure there is nothing wrong with the wiring to the ecu. But, it appears that this maybe an ecu issue. I'm wondering if the caps have leaked and are causing this issue?

If I purchase a new ecu on ebay, the ads say "be sure to check if the computer needs to be programmed by the dealer." Do these ecu's need to be touched by a dealer? I thought they are plug and play but want to be sure before I buy one.

thanks,
John

[fixkick]

i have a pyrogun, costs $15 at harbor fright.
and shows temps accurate to 1C.

reprogrammed is there silly boiler plate. this ECU has hard coded perm,ROM in the center of the processor at the chip DIE level.
there is no plug and play, one ECU fits one car, type. period
read the preamble to my ECU p/n PDF. it explains what fits what.

your ECU is fine, (well the ECT part is not fibbing Im sure.
with engine hot, and the connector on ECT pulled does it read about 300 ohms
if yes and Pyro gun agrees'
then may be the UK Vitaras, have there own, ECT? i can look that up and will later.
I dont think so because i shared my reading to RHINO may years ago ,at early hacking stages.

why not buy a 300 ohm any watt resistor. and plug it and and see if temp goes to 180.

you bought a 180f stamped on side, 180 or in C?
you using that , correct thermostat gasket the rubber ring is on all 95s.
got that , no , that cause what is on my frigid page.
any $10 dmm can solve this in 1 min. 300ohms or not>? hot? easy as pie.

http://www.fixkick.com/Cooling-engine/Fr...r-cab.html


see cut to chase there

see this, see that rule set .????

http://www.fixkick.com/Cooling-engine/deepwell2.jpg

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no paper gasket allowed in the deep well stat or the stat FLOATS and FAILS .

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this i use my gun and bam , gee this engine is 150f, thats bad. .

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in fact is first thing i notice on all cars, due to stats croaking in 3 to 5 years.

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if 150F the ECU is locked in warmup mode for ever .

[cosmic_splatter]

I installed a 180 degree stat with o-ring. I have the deep cavity as outlined in the tsb. Will try 300ohm resistor. Great idea!!

John

[cosmic_splatter]

Fixkick,

Here is an update after a morning of troubleshooting. The sensor goes down to about 250 ohms and then pops back up to 300-320 ohms (I think when the thermostat opens). I removed the connector from the ECU and i'm seeing the same 320 ohms at the ECU. I really think this is an ecu issue.

I'm going to try to get a replacement ECU. From what you said, If I order the exact same part number ecu on ebay that I have in the car, do I need to do anything to it before installing? I'm not planning on mixing and matching part numbers. Exact part number replacement.

thanks,
John