DFI Module

[Dazza VU ute]

Hi all,

I am having DFI module issues with a VU 2002 ute (Basically a VX). I have killed my second DFI in 8 weeks. Very expensive at $380 per unit. When i removed the DFI module this time i noticed it was very hot. The heat seemed to be excessive in my opinion. I believe something in the ignition circuit is causing the DFI to heat up & fail. I replaced plugs & leads about 12 months ago & coil packs about 2 years ago. I am thinking that one of the coil packs is faulty & causing the DFI to heat up so much that it burns out & fails. I have checked the DFI plug & it looks fine (no corrosion or heat/burn marks etc). I would be interested in anyone who may of experienced this type of repetitive failure & what advice they could offer. Any information would be appreciated.

 

[losh1971]

Replace the coils and make sure you have applied heat sink paste to the bottom side of the DFI..

 

[lout]

i would also replace the spark plugs with store bought not ebay plugs

 

[Dazza VU ute]

Replace the coils and make sure you have applied heat sink paste to the bottom side of the DFI..

I understand the reason for heat sink paste although, why do you need to apply when this wasnt applied from factory ?

 

[Lex]

heat sink paste although, why do you need to apply when this wasnt applied from factory

I believe it was applied (paste).

Where you getting your coil packs & dfi's?

Lot of crap getting around.

Whats killing them dfi? Possible sh#t plugs leads wiring coils?

When replacing the dfi's replace with the coils.

I get mine from the wreckers $50.00.

Now to address the killing dfi's for a start look at the dfi plug, any burnt or corroded pins? If yes clean them up.
I found one of mine to be burnt. Cleaned it up. But went to the wreckers & found a good plug, that wasn't burnt. Cut it back a good 300 to 400 mm. Then spliced it into my loom.

Its been pretty good since. I also keep one on the back floor of my wagon with the tools to change it. Got stuck on the other side of the bay, 10 minutes later l was up & running again. That was 5 years ago. I still have a spare dfi coil packs in the back of the wagon, Just in case.

Good luck & please let us (the forum) know how you get on.

 

[Deuce]

Check spark plugs, and specifically the gap (1.4mm) as I believe this is a potential cause for DFI failure.

 

[Immortality]

Stock gap should be 1.5mm +0.0/-0.1

When you say it's killed the module what exactly has it done? Is it completely dead or misfiring?

I'd replace the DFI and coils. Also plugs and leads depending on how old they are.

 

[Dazza VU ute]

Stock gap should be 1.5mm +0.0/-0.1

When you say it's killed the module what exactly has it done? Is it completely dead or misfiring?

I'd replace the DFI and coils. Also plugs and leads depending on how old they are.

Not completely dead, just misfires & carries on. I have my own tech tool to remove any code errors which has always allowed me to get the old girl home. This car has never left me stranded. I have owned it since new & it is hard for me to let it go due to its reliability. I also have got to know how these cars work & know it is just a matter of knowing how they work which i believe i have a good understanding. I agree with you that replacing the coils would be a good idea. I still have the original OEM coils that i replaced some years ago due to another issue doing the old elimination process. Thinking of putting these back in to replace the Fuelmiser coils i put in which i think are inferior. Your input is appreciated & any further input is greatly appreciated.

 

[Immortality]

You can measure coil primary and secondary resistance and see if that shows anything obvious.

You can also remove all 3 coils and use a test light over each set of outputs and then crank the engine with the starter. If the DFI module is working the test light should flash which indicates the DFI module is switching the coil outputs on/off. This might show a faulty output on the DFI. You can possibly test the other one the same way and see if it tests the same, especially if you know the coil placement on each DFI module.

 

[Lethal]

G'day All,
Y'day (10/6/23), my engine started running really rough. I limped home and started testing. No spark to 1 & 4. Bugga! Coils (Mace Eng.) less than 2 years old! Changed to a spare coil. No change!

Next! Having just completed the job, I have only just found out that the thing under the coils is a DFI Module. I changed it with one from my VR wreck that did 450k km and all is sweet. TFG!

After 29 years of owning V6 commodore and some 650k km, its the first time I have had a issue with this module.

I also thought to use heat paste between the module and mounting block after sand blasting corrosion off. The factory just used surface contact as there is no sign of old paste.

Off to the wreckers to get a couple of spares to test as GOOD spares. I go bush a lot and don't wanna get caught all too many km from civilization.