Timing changed itself... Kind of. And ultra rich when cold and sat awhile.

[myastzo]

Hi guys!

Couple of weeks rewired knock sensors, code 52 vanished, was driving yesterday from work, everything seemed okay, maft pro was showing 2 volts for vf most of the time, sometimes 0.9 volts, sometimes 3,5. Got to gas station, filled her up, and she didnt start. Cranking, cranking, no luck. Sometimes cranking stops and all lights faded, then after a second okay, cranking again. I have new battery, 1,5k miles on rebuilt engine. 37 psi of fuel pressure with vac off, 550s, Walbro, Speed density with -14% Mainscale. After an hour i thought, that if it is cranking, trying to turn over sometime, maybe its the timing? Rotated CPS a bit and it started! Died after some time but started. So, as a mkiii owner i'm fully convinced, that driving with timing light in the trunk is normal, i shortened te1 & e1, started her, and began to reset timing (Which I did dozens of times.) My timing was jumping between 5 and 15, but sometimes it kinda stayed in 10, so i bolted the cps up and got it to garage. Question: WHAT THE ACTUAL F... HAS HAPPENED? How can a car mess her timing by itself. (P.S. Before that my CPS was rotated anti-clockwise fully until the bolt, so, maybe my timing was bad then? Again, I'm 100% sure it was set right, as per tsrm, many, many times.) The car didnt threw code when i was cranking it, but when i came to garage it was showing code 22. How can it be, i've just replaced ecu temp sensor a month ago and repaired couple of brittle wires for sensors (And the ECU temp one, but not fully from sensor to ECU, only 30-40cm lenght before the sensor.) My wiring is 27 years old, maybe it's the weak part of the system?

Problem 2:

When cold and after car has sat for some time my idle afr is 10,5 - 11,5, and driving afr is 12-15!!! I'm driving like an old coot!!! 1500-2500 rpm light throttle, i'm scared to beat it now. (When my afr shows 10,5 the vf can read 2 volts, can read 4,5 volts, so i'm stumbled. Absolutely NO logic in all of this... My wideband has been calibrated a week ago):1zhelp:

When hot it is perfectly normal, around 14,7, vf is happy most of the time.

 

[myastzo]

And sometimes driving cold afr is 10 too, so it's not normal.

 

[myastzo]

P.S. My maft pro settings are pretty stock, PTT is OFF, everything was sat using quick setup for supra, VE Table 2, Speed density, All aux trigger is 0, Air temp is 0, Only Low - 800 rpm + 2-3%

 

[cinderMK3]

have you repaired the CPS wiring, or Checked the gaps from the coils?
Before I rewired my Cps it was hard to get it to show a consistent time, or start consistently for that matter

 

[myastzo]

Thanks! I'll search for info. And my little update: The car is working, able to reset the timing(Although the mark jumps a lottle around 10, but a little. I got the car up to temp and it threw code 22 again... Hmm, i think it'sthe wiring problem. But i cant understand why it screwed itself yesterday.

 

[myastzo]

The new CPS wiring seems to be working, thank god

 

[Nick M]

How can a car mess her timing by itself.

Entropy. It is unavoidable. The timing belt can stretch over time. The bolt holding the cps can also be loose allowing it to move.

(P.S. Before that my CPS was rotated anti-clockwise fully until the bolt, so, maybe my timing was bad then?

Yes, it was.

Again, I'm 100% sure it was set right, as per tsrm, many, many times.) The car didnt threw code when i was cranking it, but when i came to garage it was showing code 22. How can it be, i've just replaced ecu temp sensor a month ago and repaired couple of brittle wires for sensors (And the ECU temp one, but not fully from sensor to ECU, only 30-40cm lenght before the sensor.) My wiring is 27 years old, maybe it's the weak part of the system?

Sure. Is that ECT sensor new? How was the wiring repair done?

When cold and after car has sat for some time my idle afr is 10,5 - 11,5, and driving afr is 12-15

That is normal. Cold needs to be richer. That is why there is a thermistor in the coolant. Could there be an issue with your tuning device? Sure.

!!! I'm driving like an old coot!!! 1500-2500 rpm light throttle, i'm scared to beat it now.

Lean is mean, rich is not dangerous. Not the other way around.

When hot it is perfectly normal, around 14,7, vf is happy most of the time.

That is normal.

 

[myastzo]

1. Timing belt is new and did ~1600 miles, CPS bolt was fastened hard. The moment it changed timing was just 5 minutes when i was on the gas station.

2. Timing was ~10 btdc, it was jumping a little because of old wiring before i repaired it.

3. Yes, its brand new OEM Toyota, wiring was fixed not so good, just the 1ft long before the sensor, will do full wiring from ECU with 1 solid wire later, its getting cold in here

4. It seems my CSI was sticking open when the car was hot, so when i was turning it off it was leaking enormous amounts of gas into intake, making it crazy next time i was starting it. Now, without the CSI, it starts the same way it was. Dunno about starting it in -20C during stupid russian winter, althought i dont have money for winter tires now so i wont drive it until april. I thought cold start rich would be around 12,5-13,5, not 10.

5. Seems legit

6. Now everything seems to be fine. http://www.supramania.com/forums/showthread.php?236508-Harry-potter-and-the-secret-of-lost-VF

 

[Nick M]

1. Timing belt is new and did ~1600 miles, CPS bolt was fastened hard. The moment it changed timing was just 5 minutes when i was on the gas station.

Engine timing, is mechanical. Pick up is electronic. The mechanical part is what moved. Either the pick up moved, the belt has stretched, or the tensioner is not tight. It doesn't jump for any other reason.

2. Timing was ~10 btdc, it was jumping a little because of old wiring before i repaired it.

So it wasn't jumping between 5-15? If it is jumping around then TE1 and E1 are not shorted, or the pickup is loose.

3. Yes, its brand new OEM Toyota, wiring was fixed not so good, just the 1ft long before the sensor, will do full wiring from ECU with 1 solid wire later, its getting cold in here

It is tough to work in the winter. No doubt.

4. It seems my CSI was sticking open when the car was hot, so when i was turning it off it was leaking enormous amounts of gas into intake, making it crazy next time i was starting it. Now, without the CSI, it starts the same way it was. Dunno about starting it in -20C during stupid russian winter, althought i dont have money for winter tires now so i wont drive it until april. I thought cold start rich would be around 12,5-13,5, not 10.

If it drips, it might stumble at start up. Depending on how bad the leak is. Sounds like yours is pretty bad. Did you plug the hole or unplug the injector? CSI only fires when cranking the starter. That is the only time voltage is applied, unless it is hard wired. Then it would fire anytime resistance in the time switch is low (closed).