Jump to content

Dreaded misfire issues (sigh)


XR6TTUB

Recommended Posts

  • New Member
  • Member For: 6y 6m 25d

Hello all and good evening

 

ever since purchasing this car, I’ve been trying to fix this one and only annoying hinderence 

 

Car details ... 03 March ba xr6 turbo Ute with 5 speed manual

symptom..

 

cold start: starts normally and smooth (no miss or abnormal behaviour)

 

as as the temperature needle starts to climb, she starts to misfire,more hotter or longer I drive it, it gets more irregular. 

Alao sometimes, whilst idling and misfiring away, she would stumble,revs drop and pick up again

now, I’ve Done numerous test on the vehicle and it all seems to be within factory/workshop manual specifications

 

oil pressure - 60psi cold and 50-60 warm

new coils and plugs

new fuel reg

new fuel filter

new throttle body and updated TPS

another set of known working injectors

all new baskets around (hot and cold side)

 

 

im a mechanic by trade, so this issue has me stumped. I’ve been diagnosing this issue for the last 2 months, but I can’t seem to replicate or trigger a change whilst doing so

 

on my scan tool with live data, it seems to pull timing at idle and below is some data to look into

 

 VCTADV(VCT ADVANCE ERROR  -9.13

VCTADV2(VARIABLE CAM TIMING 2 ADVANCE ERROR) -9.63

VCTADVERR(VCT ADVANCE ERROR) -0.69

VCTADVERR2(VARIABLE CAM TIMING 2 ADVANCE ERROR) 0

VCTDC(VARIABLE CAMSHAFT TIMING DUTY CYCLE) 0

VCTDC2(VARIABLE CAMSHAFT TIMING 2 DUTY CYCLE) 0

 

hope someone can shed some light, 

also as a sidenote, car rev thru rev range smoothly (no misfire)

ecu previously look like someone has tampered with it and the numbers on the side of PCM have been changed

as I googled the numbers and came up with a F6 typhoon PCM

 

kenny

Link to comment
Share on other sites

  • Puff
  • Gold Donating Members
  • Member For: 9y 1m 28d
  • Gender: Male
  • Location: South Australia

The earlier models have a different cam timing system than the later models. 

 

If it has got a different ecu then it could be telling it to do stuff it shouldn't be or vice versa.

Link to comment
Share on other sites

  • Gold Donating Members
  • Member For: 7y 11m 10d

Did u happen to throw a new 02 sensor in?

 

Mite be dyno time though tbh, or off to ford to clear the file and reload the stock BA one in.

Go dyno though, power gains :buttrock:though that 5sp mite die after a power gain.

Link to comment
Share on other sites

  • New Member
  • Member For: 6y 6m 25d

Thanks for the quick responses ladies and gents

 

o2 sensor is still the old one, haven’t replaced it yet as the values don’t go over or under reccomended values

 

ive Rescently replaced the cams with some later model bf cams as I had the dreaded ticking and tapping noise on cold start. Sorted that problem out though

 

so when I was changing the cams, I lined up all the coloured links on the chain to designated marks on cam and balancer, seems everything is spot on, and the guides are intact and undamaged

 

one quick observation though, with everything lined up hunky doory, the 2 marks stamped on cam phasers sit slightly off middle at 11 o’clock, cause if it did jump a tooth or 2 none of the coloured links would of lined up

 

like I previously stated, sometimes car would idle fine, no hiccups. 4/10 times she would idle with a miss.

 

dyno tuning is in process, currently getting all the bits I need before I send it off (valvesprings,injectors and fuel pump)

 

kenny

Link to comment
Share on other sites

  • New Member
  • Member For: 6y 6m 25d

Another thing before I forget.

 

I had access to some vct solenoids and thought why not throw them in and see if it makes any difference

I had one issue with them, one on the engine seemed thinner without any filter screens and ones I had to replace them with are thicker and has filter screens

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
  • Create New...
'