problem with my vr

[vr1962]

hi all got a problem with my vr sedan and need help.i have done a code check and its come up normal code 12. the problem is that it is missing at about 2300 to 2500 under load.i have changed leads & plugs. any ideas thanks

[moff_man]

sounds like a coil pack on its way out. just check restance of secndery coils check all 3 coil packs and if one is low replace, or swap a know good one and test.

[kopper69]

As moff_man said, next do the coils. You have done the right thing - Start with the leads and do the plugs while youre there too. Its cheap and easy and wont hurt even if it doesnt fix the problem. Next are the coil packs. These generate the voltages to send down the spark plug leads. They are pretty reliable but do fail. You remove the coil pack (There are 3) and measure the primary and secondary resistance. Gregorys describes the procedure and the expected readings. If one coil shows a reading out of the range, it should be replaced. If you take the readings I can find the expected results to compare.

You can narrow it down a little more. You need to get it to a stage where it is faulting, either a friend in the car revving it or pulling on the throttle cable from the engine. The car may only do it under load, which means this test wont work. You then unplug the injectors one at a time. As each injector is disconnected the engine will run funny, you will notice the difference EXCEPT for the cylinder that is faulty. When you disconnect this injector there will be no change because the cylinder is not firing anyway. You then know which cylinder is not firing and this can help you get the correct coil pack.

It may also turn out to be the DFI module, the little black box that the coil packs are sitting on. Your best bet might be to get a friend with a VR (VP or VS would probably work too) take the whole DFI module out with coil packs (only a few screws) and see if that fixes it. You can probably buy a secondhand set of coil packs with the DFI module for a good price off ebay or wreckers.

[vr1962]

thanks guys i might swap the one out of my wagon and see if that works. thanks again for your help