Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Ecotec Problem Has Me Stumped

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
Hi guys,
I've had a bit of a strange problem with my VX the last few months that I haven't been able to solve and I'm wondering if anyone has encountered the same thing as I haven't been able to find any info on it.

Whats happening is once everytime I start the car and drive off somewhere I'll lose some power and get a really horrible crazy clacking noise the car retards the timing and the noise stops the check engine light comes on and doesn't happen again until the car has been turned off then started again. This can happen immediately after I drive off or ten minutes later and I can never get it to replicate the problem when I'm not driving even letting the clutch out slightly with the handbrake on to put it under some load does nothing (not something I've done often)

Sometimes it's barely noticeable most times its mild and once it left the car unable to drive up a hill till I stopped for about 5 mins and turned the car back on so whatever it is reset.

I have been trying for months to work out what it is as it's the only car me and my partner have, we don't drive far or unless we absolutely need to at the moment because of this and it's becoming frustrating.

So far leads and coils have been replaced and plugs were only 1000kms old when this started. Although I had my alternator die and it started happening after the alternator was replaced however I've had this alternator tested and it's working fine the only codes I got last time I checked were fir the knock sensors which presumably are responsible for retarding the timing and keeping the problem under raps, I've also recently pulled all the plugs out made sure there gap was still correct at 1.4mm and cleaned the ends of them the two under my leaky rocker cover had some burnt oil on them presumably because of that bit otherwise they all seemed okay still I've uploaded a photo I took of everyone of them (maybe you guys can spot something I couldn't) and I've got a video of the sound it makes though I managed to get a video on a farily mild version of the noise but if you turn it up you can definitely hear it. Youtube link is at the bottom of the post.

Things are very tight at the moment and I don't have money to just take it to holden for there scan tool check either I've hooked it up to my laptop but wasn't able to get it communicating with the ECU properly (DIY cable, I've got a lot of electronics experience) but I could still reset faults like the airbag after I removed the drivers seat to clean the carpet at one point. I'm not new to working on cars and I've got all the gear to fix it once I know what's wrong (please don't take that the wrong way I'm not trying to be arrogant I'm just stating I'm not a complete idiot) so if you've had the problem before or can think of something I haven't It would be greatly appreciated.

Also it's worth noting that both me and my partner drive like grandparents so it's not due to being thrashed.

I've doubled up on a couple of photos where there was different angles showing the ends differently. Also it's worth noting that I think the gunk on the end of one of the spark plugs is from scraping something off the side of the block when I first put it in. I doubt the engine would run if it spat chucks like that.

The Noise is a bit faint here but you can hear it, its definitely easier to hear when i play it on my phone though compared to my pc speakers the extra base makes it heaps harder to hear ill put a better video up if i can get one https://www.youtube.com/watch?v=6AJaTyCMOKE
 
Last edited:

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
I'll upload the photos of the plugs when I jump on my computer later for some reason the app keeps failing to upload the photos
 

deserthead

Well-Known Member
Joined
Oct 20, 2004
Messages
1,084
Reaction score
74
Points
48
Location
Cairns QLD
Members Ride
VS III l67 Column Shift Ute
Mate I had a similar issue with a miss. Would come and go intermittently. ECU would pull timing like crazy and it would ping its head off.

Long story short, the connector to my DFI module was rooted. Like proper shagged.
It had a hot joint in it, this hot joint fried the module essentially.

I replaced the connector, spliced it into the loom, and used the same DFI module. Missing was way better but still there.
Picked up a new DFI module and viola, have not missed a beat since (touch wood).

No fault codes ever popped up and symptoms were hard to diagnose as it was always pointing toward a specific component having failed, not a connection.

Worth a look anyway.
 

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
I'll give it a look, I replaced the DFI when i did the coils and everything looked fine those aren't cheap hopefully its okay :/
how did you identify the problem with it? was it pretty obvious one of the joints were buggered when you looked?
 

Immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
22,475
Reaction score
19,924
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX Calais II L67
I can't really hear anything but with issues like this start with the basics. In your case I would suggest starting with cleaning the MAF. A dirty MAF can make the car run lean. When was the fuel filter last changed?
 

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
I don't think the fuel filter been changed since I bought the car 3 nearly 4 years ago :/ admittedly that one slipped my mind, I'll give the MAF a clean and see what happens
 

lout

Well-Known Member
Joined
May 13, 2006
Messages
5,492
Reaction score
4,138
Points
113
Age
60
Location
Langwarrin Victoria
Members Ride
VXii Executive V6 , VYii Adventra LS1
thinking it must be a decent knock to retard the timing that far
just to clarify does it lose power before the knocking noise or when the knocking starts
suspect DFI or ECU but unsure how to pin it down further
if the alternator was overcharging it could have fried something
there is a timing circuit that is enabled at start that locks the timing to 10btdc? if that circuit is malfunctioning could be your problem
dont have any info with me
 

oska

Active Member
Joined
Oct 14, 2010
Messages
817
Reaction score
51
Points
28
Location
melbourne
Members Ride
vx custom 600RR
I would replace the CAS

when they go faulty a lead breaks inside the sensor and makes a bad/intermittent connection and cause some really strange problems
 

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
CAS has been replaced in the last 6 months too with a Delphi was one of the first things I suspected I'll give the DFI a look tomorrow when I clean the MAF, would it be worth getting someone with a Tech 2 to look at it? Can it run any tests beyond checking codes that would be worth trying?
 

VXPL

Member
Joined
Jun 22, 2014
Messages
42
Reaction score
0
Points
6
Location
Brisbane, Queensland
Members Ride
2001 VX S Pac Manual
It loses power when that noise starts, but overall it feels like it's lost heaps of power and is running really rich by the smell of it
 
Top