L67 going into limp home (I think)

[ev351]

Hi everyone, Its been a while since I have been able to play with this but I got a chance today. For the last few months I have been using spare time to relocate the diff center to the middle of the axle to eliminate universal / driveshaft vibration. A bit of an ordeal, but its oh so smooth now.

But back to this problem of intermittent performance.

I have to logs here from tunerpro.

The first is with the car having VERY limited power at wide open.

The second, is after i stopped the engine, removed the memcal, powered back on, wait for the fan to come on in limp, then power off, re fit memcal, and restart engine. Then I have full performance You will note in the second log there is lots of timing pull, but the engine has WAY more power than in the fist log.

Also, in the first log there is no timing pull. But still no power.

The only thing that i can say that i have noticed is this:

If the car is left for a period of time, say overnight, then when you start it has no power. If you reset the ecu, then it runs fine until it is left overnight again... Im not sure if this helps. But the issue is not knock retard, it is much more pronounced. (in saying that im waiting for my water injection kit to arrive .. just to get rid of the little retard that it does have..)

Also, in the fault.xdl log, the place that i notice no power occurs at about nine minutes. you can see a full throttle pull there, and the 'going properly.xdl' log, the first full throttle pull where you can see lknock retard, the thing is going very well....


Hopefully someone has seen this before as it is becoming really annoying now..

Ev.

fault.xdl

[VX L67 Getrag]

You need to sort out fault codes 47 & 71 before anything not sure what causes them but would be pretty serious things to sort out!

[ev351]

I saw 71, i know its engine speed low, but i cannot see how its being set as the RPM is being read correctly and the engine is idling perfectly etc. I will look into it. If anyone has seen this before let me know. I did not even notice code 41.. I shall look it up now!!!

[ev351]

Ok, so 41 is a fault with the EST, I just checked the definition, and will do the check that is outlined when i get near the car next. I reckon that is going to be the problem. I dont understand why i didnt see that?? Are you just looking at those logs in tunerpro or something else???

[ev351]

i meant code 47... but you knew that

[Holden202T]

you can use the item list in tunerpro to see what codes are set/clear, once in that view up the top there is a pull down menu usually will have engine data in one view then error codes etc

[VL400]

At 4m10 in your first log you have lost the 18x signal from the ignition module or CAS. The module or CAS may not be delivering the spark advance the PCM is commanding when the error occured. There are some other odd spark retard things going on just before that, but havnt looked to see if its accel or decel maybe doing it.

[ev351]

OK, so I got some time last weekend to track down this fault. First i swapped out the EST module. Of course it wasnt that. That would be far too easy! So then I swapped the crank angle sensor. Thats a pretty straight forward job if the motor is in a Holden, but in the sierra, its a little more involved. Remove bullbar, front panels, radiator. Doh! Anyways, The Harmonic balancer look a bit crappy, but i figured it must have been that way for ages, (Should have known better, I have got the rattles in many holdens before) Anyways, I put it all back to together and went for a test. I got to drive for about five minutes before the rubber in the balancer failed. Not Happy!

So i took it back to the shed and ordered a new balancer. Its arrived and im hoping to swap it on friday night! (what else would you rather be doing?)

The only thing that i can say is that I thought it started with far less cranking after i changed the CAS. Im not sure how much 18x has to do with starting?

So hopefully can go for a cruise late friday night for some more testing!!!

Then on Saturday its on to the water injection!!!

[charlay86]

18x is used at lower engine rpm (400-2000) for more accurate spark control

[Holden202T]

i would say 18 x has alot to do with cranking