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[V6Astra F]

Hi

Connected the laptop on the car last night when i noticed something strange , the spark angle before tdc is -9 to -8 when you touch the accelerator it goes up , but should it be at a negative on idle ? .



Thank You

[Marks DTM Calib]

Yeh....should always be negative even at idle

[V6Astra F]

When you touch the accelerator it goes into the positives cant remember how mutch  , last two days ive had a problem with hesetation on acceleration going to check my afm tonight but i suspect it might be my fuelpump or fuelpump relay thats acting up .allready swaped out ht leads will do the coilpack aswell , the only error code i have is code 46 but we dont have the sai pumps or relays for the sai system here so getting them is a bit of a pain .

Thanks

[MutantCav]

Looks like everything is reversed on your MOC-PO readout  

[V6Astra F]

its a demo   i got because the abcom version i got with the cable is a mess , not everything is english . the local agents here wont look at my car because they say there scanners cant read it  :-? . What is a good program to use ? its the serial tech 2 one , the usb elm 323 doesnt seem to work on the motronic 2.8.1

[V6Astra F]

where can i get the timing specs of the motronic 2.8.1 on the x25xe , the mechanic that has my car now wants to repace the timing belt and open the engine to check the pickup on the crank . he says its supposed to be 8 to12 degrees and not -8  , i dont want to get ripped off . he wants a proof that its supposed to be like that . i know we did ground pin 42 so the ecu knows its on a manual box .    code 46 just came back after i replaced the relay

[Kevin Wood]

The timing belt has no bearing on the ignition timing because that's taken directly from the crank sensor.

The crank pickup is a variable reluctance sensor which detects marks milled into a rotating disc. I can't see any potential for this to fail in such a way that the timing just shifts. Failure of the sensor is relatively common but it results in a code 19 in the ECU and normally running / starting problems as the ECU can't synchronise to the pattern on the rotating disk. If the ECU synchronises reliably there is no code 19 and the timing is correct. End of story.

So, both of your mechanic's remedies will be a hiding to nothing, IMHO. The engine ECU will be controlling the timing to stabilise the idle, so there will be no "correct" value. If he can't understand that, you need to find another mechanic IMHO.

The SAI system is only used for emissions during warmup. Has the system been removed from your car or did it never have it?

I think the code you are getting relates to an open circuit on the line that drives the SAI relay coil.

Kevin

[V6Astra F]

hi

thanks for the info , had a code 19 but the shielding was damaged that was repaired and it was sorted , was there a diffrence between the x25xe and c25xe crankshaft position sensor ? . the cars we have here did not have the SAI system so i always had the code , i got a relay and tought that i cured it but the fault came back after i drove a bit so ill check the wires tonight again , my dual ram intake system also doesnt want to work , got vacuum when you test the wires with the ignition on you have a eath and power when you start the car both wires are live and the earth is gone  :-?.

[Marks DTM Calib]

The air injection code will not be the relay, it will be the vac actuator (as its missing). A 1K resistor will sort it (usualy)

If your ignition timing was really as retarded as that then you will have pretty much no power!

And as Kevin has stated, the cam belt plays no part in the ignition timing

[V6Astra F]

great so that means that i have to find the wires for it and get a resistor between them . if the machie did get the cam timing messed up say one tooth to slow when he replaced the belt , would that give the same symptoms ? .but i think that would give a eml light i think, the car feels strong and i can hit the limiter in 5th of the f18cr . it has a flatspot but im trying to source the 3.8bar fpr and some cams  , dont think it can be the fuel pump but it is the one i had on the old 2l motor .

fogot to ask , could it be that my tech 2 is giving a wrong reading ?