c20xe missfirein badly need help

[s14a]

well lads bought a car yesterday, happy with it, 1 slight problem when i was drivin i noticed if you were cruisin on very soft throtle in any gear, any speed, then full throtle it would hesitate and backfire out the exhaust at the same time, then accelerate fine.... it was like it was overfueling badly....

then last night got home it got alot worse, left it for a while, started it and found it very hard to even move it, backfirin in the inlet and exhaust, 2day it would barely do 10mph it got that bad....
i disconnected the airflow meter when it was running and it seamd to run the same which has me thinkin thats the problem, any ideas??

changed colant sensors aswell, no difference...

[db_1.2]

Could be head gasket, sounds like it, or bent valves, something down that route.

[s14a]

jeses relax dude lol, theres no smoke out of it, no funny noises from the block, no mayo on the oil cap or in the header tank, defo not that...
thanks anyway, any other ideas, coilpack was changed recently aswell...

[edens-xe]

i know this may sound silly but it happened to my xe, check all the electrical connections and the earths and make sure there clean, also check for air leaks on the inlet side like pipes e.t.c. hopefully these may be of some help for you

[s14a]

checkd for air leaks but never thought of earths, good thinkin cheers
did it happen as bad to yours?? which problem was causing yours?

[Will F]

Doubt its earths tbh, if it was it wouldnt even start...

I would have said massive air leak, but if you have already checked.... Assuming its not bringing the light on?

[meritlover]

check, most of all obvious things like put timing light on each plug and see if its spark thats breaking down or if its an electrical missfire. if the plugs fire constantly then it must be due to fueling.it could well be the AFM as this would have a much effect by disconnectionl. try and swap for friends spare? check the plug leads are ok and on in the right order. make sure connections for engine sensors are clean and not full of corrosion.
if there is still no luck. try a compression test and check the cam timing is right.

[db_1.2]

I still recon its head gasket split across the bores, espiecially if its the original one! The original ones GASH! I been there myself and had everyone say ''oh no not a head gasket, check your backbox!'' but when i took the head of it turnt out to be split completely across 2 cylinders and leaking on another.

Does your sound a bit like a scooby?! Lol

[meritlover]

well if this is the case it should be easy to find with simple compression test.

[db_1.2]

Yup

[hendrix]

I've got EXACTLY the same problem with the calibra. only does it once the car warms up though so I suspect its when the ECU changes into its closed loop (think I got that right).
On mine (coilpack model) the sensor housing on the exhaust cam was completely full of oil, I don't know if its meant to be like this but when I cleaned it all out it ran fine until it filled with oil again. Not sure if that cam is supposed to have a seal on the end cos mine doesn't :confused:
Try that maybe mate

[craig green]

I've had bad earths give me a misfire on an XE before. Didnt like full throttle one bit.

I'd spray WD around the inlet whilst its running & look for bubbles. The rubber seal between SFi box & TB is prone to leaking too.

If you know of a donor car you can borrow the AFM for a quick drive etc. & remove the plugs & examine them, check gaps etc.

You say the CTS is changed, what about the 2 wires? ARe they OK & with a good continuity?

[meritlover]

Mr Green. manifolds work at a vacuum so you would not likely be seeing bubbles when running.

[mikey14sr]

Mr Green. manifolds work at a vacuum so you would not likely be seeing bubbles when running.

In theaory, yes, in practice, I've seen it quite often. Although the biggest indicator of a leak would be a change in revs from the engine when WD or similar is sprayed near the leak.

[s14a]

cheers for the help lads, 4got to say when car is tickin over the revs hunt alot....

[s14a]

oh and ecu light is not wired in2 the digi dash so can do fault test...

[mikey14sr]

oh and ecu light is not wired in2 the digi dash so can do fault test...

Get it wired in then, not having it connected can cause faults on it's own.

[hendrix]

Yeah mine hunts really bad too....sounds like exactly the same problem.
Let me know when you find a solution

[Will F]

oh and ecu light is not wired in2 the digi dash so can do fault test...

:roll:

Pointless asking questions when you havent done the basics.

[s14a]

i dont know how to wire it, otherwise itd be workin, no1 around my area has red tops, they all drive reliable jap cars lol

[s14a]

Yeah mine hunts really bad too....sounds like exactly the same problem.
Let me know when you find a solution

mine is a coil pack model 2, hopefully your right:D

[hendrix]

I took mine to a mate at vaux and it wouldn't even communicate with tech1/tech2 so they couldn't help lol

[meritlover]

In theaory, yes, in practice, I've seen it quite often. Although the biggest indicator of a leak would be a change in revs from the engine when WD or similar is sprayed near the leak.

this has never happened on any engine i have worked on ever. it is not possible. if an engine sucks, how can it blow out a hole?:thumb: yes the engine not 'may' change. but considering how rough this engine is. i think you should be able to put your finger in the hole if it was a manifold leak. but if this man has not performed basic checks then he will be in little hope of having nice running XE

Mr Mikey does not like me and wishes to discredit my sayings. but that is fine with me. some people are just like that.

[hendrix]

Hang on there son!!!!!! lol
Mikey is very good with engines and modifying so I would listen to what he has to say!!!!! :thumb:

[meritlover]

it is ok Mr Hendrix, mikey does not know me or what i have done to many engines either. but none the less, mikey does not like me and takes many opportunity with his friend stuart to discredit sayings.

[s14a]

this has never happened on any engine i have worked on ever. it is not possible. if an engine sucks, how can it blow out a hole?:thumb: yes the engine not 'may' change. but considering how rough this engine is. i think you should be able to put your finger in the hole if it was a manifold leak. but if this man has not performed basic checks then he will be in little hope of having nice running XE

Mr Mikey does not like me and wishes to discredit my sayings. but that is fine with me. some people are just like that.

i firstly am not a mechanic so i can do fcuk all myself, i changed the coolant sensors and checkd for air leaks, after that i was lost, that is my limitations to basic checks which is why i am askin for advice on here

[meritlover]

normally the MIL is just an output from the ECU through a bulb to the ground. is this not possible to investigate/install something to perfom a checks? there must be a person on here that has a pin out for a XE engine ECU?

[s14a]

ok lads bit of a update....

checkd exhaust cam sensor housing and it was full of oil so i cleand it, still ran the same???
does that mean there is a seal gone ye?

turns out the ecu plug was loose i think, changed it and the fuel pump relay at the same time bit i reckon it was the ecu...


car is still overfueling slightly, still backfires ever so slightly...

[meritlover]

how are you determining the over fueling? is it mis fring or back firing?

[s14a]

its still slightly does both at the same time, im back to what it was like when i collected the car so the ecu plug must have came loose in the meantime....

cruising along and floor it and for a second it will hesitate and backfire at the same time...

[meritlover]

TPS sensor? perhaps maybe the accel enrichment is not working due to a poor TPS adjustment or fault and the mixture is leaning out causing a hesitant???

[Stoo]

i had it on mine

cleaned the Idle control valve
changed the AFM

new plugs, leads, rotor arm dizzy cap

cured it

[meritlover]

that is remarkable that you had all those faults symultaneously!!! that would have taken a long time to determine the cause.
did you work out exactly what part was the failure part!!!!?

please?

[s14a]

plugs and leads are fresh on it, not sure about cap and arm

il clean the idle control valve, if not fixed then il be gettin a afm, there hard got over here so il be leaving it till last...

cheers

[meritlover]

will you be checking the TPS for me mr s14a?

[s14a]

that is remarkable that you had all those faults symultaneously!!! that would have taken a long time to determine the cause.
did you work out exactly what part was the failure part!!!!?

please?

pure lucklol as i said already im not very good mechaically so i usually check everything is on right first them move on2 the harder stuff when my mates are there to help....
luckily it worked this timelol

[s14a]

will you be checking the TPS for me mr s14a?

again i dont have a spare so it will have to be last, unless there the same on the early xe engines in that case i can swap the 1 from my gte...

[Stoo]

i just freshened the lump up with new bits and it ran fine

[mikey14sr]

There could allways be the possibility that the cam belt has jumped a couple of teeth, therefore putting the timing out.

[meritlover]

...........
if there is still no luck. try a compression test and check the cam timing is right.

:thumb: right again Mr Mikey, iam of no threat to you

[s14a]

i had it on mine

cleaned the Idle control valve
changed the AFM

new plugs, leads, rotor arm dizzy cap

cured it

only after think theres no arm or cap on this, its a coilpack model..

[Lee]

What plugs are in it? XE's are uber fussy about their spark plugs.

[s14a]

ok mate il try that cheers