The proper/accurate way to set timing, idle, tps

[AussieFX]

Originally posted by My_Probe_is_faster

AussieFX, I know that if I set my timing higher, the car idles higher, and vice versa. Since I set the timing right my car has idled properly.

93 GT with ZE ECU

Nick

Hi nick and please understand that Im no guru but have opinions relative to this matters as you do yourself.

I also have played with the timing on my probe and as you have noted, it also effected my idle speed.
This is documented in the technical manual for base timing and idle.
I noted on my probe that if I had the base idle set around the 750rpm mark(100 above) that occasionally I would experience the sticking 1200 idle problem.
Slightly reducing the base idle corrected this for me at least.


I was of the opinion that adjusting base idle effects specifically the starting performance as the PCM is scanning the CKP1
during startup conditions.
This is why we set base idle with the ten and gnd jumped to indicate to the PCM we are setting base idle, so continue scanning CKP1.
This is detailed also in the manual you have.

I found it interesting that when I unplugged the CKP2 sensor(crank location), that the car will not start at all. Seems to contradict what the manual states about start up protocol!
This is why Im uncertain myself as you can see.

Once the engine has started, the PCM will then use CKP2(crank location) to indicate tdc readings.
CKP2 readings are generally twice that of CKP2 readings.

[LowGT]

I think my car is missing the little plate over the belt that you adjust the timing to. Can someone post a pic of the plate so I know if I'm missing it or not? I just put in a remain disty and didn't mark it's location because I was going to follow this procedure to set it.

Guess that backfired on me.

Dan

[Mr. MX6]

It is actually part of the timing belt cover directly 10 o’clock from the drive pulley (the one in the middle @ the bottom)

[fearless racing-probe]

is the timing the same for the klze. just wondering because it still dies sometimes and occasionally has a crazy idle, figured i'd check timing, tps and all my vacuums tomorrow

[My_Probe_is_faster]

Originally posted by fearless racing-probe
is the timing the same for the klze. just wondering because it still dies sometimes and occasionally has a crazy idle, figured i'd check timing, tps and all my vacuums tomorrow

Yes, timing is same(as far as I know). Sounds like a vacuum problem maybe.

Nick

[greggomon]

The proper/accurate way to set timing, idle, tps

Just changed Timing belt, water pump, valve cover gaskets, replaced vacuum lines and added Pheno spacers.

Idle was high and fluctuating.
Followed your write-up and my car is purring again at idle.

Thanks for the info.

[tesmith66]

[K Brice]

Good post/info but you left out one critical step (unless I somehow overlooked it)
When installing a new TB plate for your bigger TB you really should adjust the backstop screw. If you want to make your idle perfect you should weather you have a 100mm TB or a stocker. It’s really easiest to adjust the backstop while you still have the TB off, But you can do it just as well with just your intake removed.

It is critical to adjust this stop before your Idle air screw and TPS because adjusting it will affect TB plate seating (how much air slips by) and the position of the TB shaft that drives the TPS



Brice

[K Brice]

Originally posted by My_Probe_is_faster
There's no continuity, because the ecu uses that continuity to know when the throttle is closed. Once it is open enough, then the continuity breaks and the ecu knows you're opening the throttle.

AussieFX, I know that if I set my timing higher, the car idles higher, and vice versa. Since I set the timing right my car has idled properly.

93 GT with ZE ECU

Nick

oh yah
when I ferst read that I was thinking you were sayint that the ecu mesures continunity between the backstop screw and the shaft. I was like

So basically you are just giving the TPS a little "slack" In other words It won't read continunity untill the TB shaft rotates X degrees due to throttle input. It's a good idea because the tb might not seat fully closed or exactly at the same 100* closed position every time. Don't give it to much slack or you will have poor throttle responce and hesetation. Adjust it to far the other way and you will be "pre loaded" I.E. TPS never reads fully closed
even when the Butterfly is.

There is no One size fits all spacer/feeler you should use. It will probably be diffrent for each TB because of the diameters and seating issues. Should be more accurate that the "back it off till the fans do their thing way though" Sounds like you found somthing that works.

I backed my TPS off a little to far once and had major hesetation when I floored it. This adjustment is even more critical the bigger diameter you go on the TB because because The TB butterfly now opens at a faster rate (acceleration = speed times time times time or somthing and you now have a bigger diameter so really you can never correctly calibrate the TPS to a modded TB)

check out my TPS mod idea that corrects this problem

http://www.probetalk.com/forums/show...adjustable+tps


P.S.

Love my 65 mm TB
I adjusted my TPS,IAC,Backstop, and air bypass screw in order via the Ford tech manual and My idle has been perfect ever since.

there are really only foru componets at play here.

Just adjust in this order and you will be fine

Backstop screw
Bypass screw
TPS

IAC (cant really adjust)


Interesting about the ignition timing though.
Ignition timing should be fine if you have never adjusted it or removed the Dissy so theoretically that step could be skipped by those that don't have access to a timing light but want to try and improve their idle.

Brice

[Fastest95PGT]

The backstop would be necessary to adjust assuming the plate would fit flush at a specific stop point. This is definitely the first step though if it does fit flush. If it does not, then you need to make it flush first.

However, quite a few people who participated in Gregg's BB (myself included) recieved TB's back which do not fit flush... thus forcing it back to the original stop point causes the idle to drop as the flow is restricted because the butterfly is actually closed.

[noid_19]

timing/tps questions

the thread states to check the continuity of the idle air control, but how do you get any voltmeter leads on it the angle and space is impossible.?

also when i am setting my timing should i first set the rpm to a specific rev? my timing seems to go out if i change the idle rpm after.

if my idle screw is open 3 turns it idles at about 1100rpm if i set the timing then and after adjust the rpm down to 650 then it puts the timing out. which should i set first the idle or the timing?

[cre3d]

Bump, why is this not in the archive? Or at least sticky? So many people with idle/tps/timing questions everyday...

[seagull369]

Ive never used a timing light on my personal vehicles and havent needed to (yet). The backyard mechanic way I do it is to simply advance the timing incrementally until I hear a knock under load. I then retard the timing until the knock goes away. Easy enough?
________
Chrysler slant-6 engine

[brian2305]

I think thats cheap excuse hell a timing light is only like what $30.00. Thats not worth messing up an engine or having to deal with poor performance over $30.00. Yes it does make a difference ask sauceman how much faster his car was once we adjusted timing acording to specs and his was advanced to like
14 deg.

[Mr. MX6]

Yea but our cars ECU in conjunction with the knock sensor controls the advance .. so it wont make the car ping/knock no mater what ..
it just cant advance the timing to the max if it aint set right.. (IE it can only advance/retard a specific amount from the “set” point.. )

you probobly arnt geting the most from your timing being set that way (unless you get it by a fluke )