Misfire - fr 3 plugs brown. rear3 black ?

[MOM]

Hi.
My t350 has just developed a misfire from idle. Just looked at the plugs & the front 3 are a nice light brown & the rear 3 black. (No 4 wet with fuel)
I this normal ?
Does the coilpack work in 2 halves ?

[twinreal]

In three pairs: cylinder 1+6, 2+5, 3+4
So maybe there is a problem with the fuel mapping (AFR). Here you have two banks and one of the fuel ratios can be too rich. Maybe a faulty lambda sensor or connector.
It's a good idea to connect a laptop and have a look to the ECU values/errors
EDIT: or engine just flooded ?

Edited by twinreal on Monday 24th March 10:52

[MOM]

Thanks for response. Dont think its flooded as does start.

[MOM]

Hi. Is the software easily available ?

[twinreal]

Yes, you can use the standard software: http://www.varleyhyd.com/images/sag/TVRDIAGNOSTIC....
or the version from EvoOlli : http://www.pistonheads.com/GASSING/topic.asp?h=0&a...

[MOM]

I will get the diagnostic cable but now do think its the rh lambda sensor as looked at the varley bible & seems to make sense as each of the 2 sensors looks after 3 cylinders front to rear. Just wish i could get underneath to check 3 wire or 4. Its a nov 03 car. Where best to buy from....seems a big difference in price ?

[stlol]

twinreal said:

In three pairs: cylinder 1+6, 2+5, 3+4
So maybe there is a problem with the fuel mapping (AFR). Here you have two banks and one of the fuel ratios can be too rich. Maybe a faulty lambda sensor or connector.
It's a good idea to connect a laptop and have a look to the ECU values/errors
EDIT: or engine just flooded ?

Edited by twinreal on Monday 24th March 10:52

I thought the coils fired in two banks of three ???, I would also hazard a guess of a faulty lambda on 4,5&6. I would say you have 4 wire on that year, can you not just unplug one where it comes up and into the loom.

Edited by stlol on Monday 24th March 19:34

Edited by stlol on Monday 24th March 19:37

[Basil Brush]

MOM said:

I will get the diagnostic cable but now do think its the rh lambda sensor as looked at the varley bible & seems to make sense as each of the 2 sensors looks after 3 cylinders front to rear. Just wish i could get underneath to check 3 wire or 4. Its a nov 03 car. Where best to buy from....seems a big difference in price ?

As said the engine runs as 2 banks of 3, each with TPS, Lambda sensor etc.

If it's the same wiring layout as Tuscan the plugs for the lambdas are on the right side of the engine, above the exhaust manifolds so should be visible under the bonnet.

[twinreal]

stlol said:

I thought the coils fired in two banks of three ???, I would also hazard a guess of a faulty lambda on 4,5&6. I would say you have 4 wire on that year, can you not just unplug one where it comes up and into the loom.

Edited by stlol on Monday 24th March 19:34

Edited by stlol on Monday 24th March 19:37

The coil pack has three internal coils. Two plugs are fired at the same time (wasted spark) in the above described pairs.
In opposite of ignition the injection is done in two banks of three injectors. And one lambda each bank.


Before buying a new lambda you should check with the software. As for testing you can unplug both lambda connectors and see if it runs smoother.
With the software you can also check if the throttle pot of the second bank is maybe faulty as this can lead to a lumpy running engine

Edited by twinreal on Monday 24th March 20:57

[MOM]

Good advice thanks. Realised i have a very local outfit who have the software (scole engineering).
Interesting that the injection is also 2 sets of 3. I did have a quick look but dont suppose they have seperate fuses ?

[twinreal]

Here is a good thread about ignition coil and firing order: http://www.pistonheads.com/gassing/topic.asp?h=0&a...
and the last post in this thread describes the "two way parallel" firing: http://www.pistonheads.com/gassing/topic.asp?t=749...
I think i understood the principle but i'm not able to explain it in english (wish i would have learned all my vocabulary in the english classes when i was a teenager... )


@MOM, here's a pic of the lambda sensor connectors of a 2004 tamora. This is already with the earth mod, so maybe yours looks a bit different:

[MOM]

Thanks for all this. I am currently struggling trying to get the pc to talk to the mbe through the 3 pin. Will post when i have a breakthrough

[PetrolHeadPete]

Dont forget to press the immobilizer

[MOM]

Thanks. Have just posted update in the new software thread with a screenshot.
.
now connected but need advice on throttle pot reset

[MOM]

Update: thanks for everyones help. Have just fitted new tps to rear(456) & was much easier than i thought it was going to be. Reset throttles on software & after about 2 mins everything sorted out nicely. Just to note after i reset throttles the adaptive cut in on 123 . Hadnt before even with fault & then errored. But switched off & cleared it & then it settled down.
Thanks again & love the software. Def be interested in a small board diagnostic unit.
Mark