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When mine would do it, it would foul a plug. I think it has something to do with (but never bothered to look into it further to find out for sure) the fact that maybe the spark is fired sequentially but the injectors are fired as a batch and depending on where the motor stopped when it was turned off previously, determined whether one of the cylinders had to go through all the strokes while the injectors are pumping before the spark plug got sent the signal to do it's thing, and by then it was too wet/ rich to fire properly, hence the cough and the rough running until the plug cleared. Mine did it on both 6 and 7 heat range NGK plugs.
 
Well none the less I will still feel like a cock if the noises continue. I think I need to change my ecu anyway and the injectors will be changed aswell hopefully soonish.
 
both of my jspec motors backfired on startup for years now and again,funny thing was that they did it even with aftermarket ecu.one was a haltech and the other was a LINK ems.i suspected the injectors.when it backfired it always cranked over like it had a blown head gasket and had lost compression on a cylinder or two .and ran on three cylinders for a minute
 
rob323 said:
When mine would do it, it would foul a plug. I think it has something to do with (but never bothered to look into it further to find out for sure) the fact that maybe the spark is fired sequentially but the injectors are fired as a batch and depending on where the motor stopped when it was turned off previously, determined whether one of the cylinders had to go through all the strokes while the injectors are pumping before the spark plug got sent the signal to do it's thing, and by then it was too wet/ rich to fire properly, hence the cough and the rough running until the plug cleared. Mine did it on both 6 and 7 heat range NGK plugs.


may be onto something there, i do recal it wasnt always on the same cylinder.
 
Just got the car back from the mechanic and he thinks rings and valve stem seals are rooted! Again it is still possible its just the shit turbo but eh I ain't going to buy a new turbo and manifold if theres still a chance the motors not good.

Feeling very shattered!!
 
Turbo nutter said:
Just got the car back from the mechanic and he thinks rings and valve stem seals are rooted! Again it is still possible its just the shit turbo but eh I ain't going to buy a new turbo and manifold if theres still a chance the motors not good.
Turbo nutter said:

Feeling very shattered!!

Why does he think that? If he thinks thats the reason for the motor bloking smoke, Id start pulling things apart for a look before writing the motor off. has he done a compression test to support the idea of the rings being on the way out?

If its bloking oil smoke...
Would it be worth him checking before and after the turbo to see if its the turbo dumping the oil into the exhaust. (asuming the temperatures in the exhaust manifold or dump pipe wont burn the oil compleatly, it should leave some nice gunk.)

What i would do is, undo the front pipe from the dump pipe, see if its all coked up with half burnt oil. (When mine blew up it shat oil everywhere.)
If there is oil in the dump and front pipe...

Unbolt the turbo or the exhaust manifold and look inside the manifold and see if it's coked up with oil aswell.

I would say if the dump is dirty but the manifold clean, its the turbo dumping oil into the exhaust.
If the oil is coming from the engine (valve stem seals or rings) you probably wont see anything unusual in the exhaust manifold or the dump as its probably burning in the motor.
 
if you do a compression test and it comes back bad then do a leakdown test and this will give you a good idea of where the cylinder is loosing compression.
 
if your blowing smoke then take the exhaust manifold off and have a look at the exhaust ports on the head.any port that is darker than usual or black/wet looking then thats your problem cylinder to check.
 
Got the old girl back last week! Had the thermostate replaced and the thermo fan swapped with a secondhand one I brought aswell! So no more coolant leaks and no more over heating for now. Still need to workout if this motor is rooted or not! Hopefully the taxman gives me a big fat return again this year so I can get this car to a respectable level.
 
Ok been a while since i've posted, Last week for what ever reason which I don't no about the car started stalling everytime I pull up at the lights so thats been a real bitch.

Then today was doin abit over 100 then all of a sudden the car felt gutless! When taking off from the lights first seems abit off then once in second third or forth theres no power and anything other than really feathering the accelerater the car shudders. Can't really go over 3-4000rpm. Wondering if theres no compression or if the turbos stuffed or is is throttlebody related? Any hints or help would be greatful.

Really can't spend to much at the moment thats why I was trying to get threw the next couple of weeks.

Tony
 
almost sounds like the balance shaft belt broke and maybe jammed in the timing belt causing it to jump a tooth.that has happened to me before.if the motor vibrates real bad about 4000rpm,then thats definately balance shaft belt.if so then check your timing
 
Thanks Tim but already got it sorted! Took it to the guy I should always use but have not wanted to spend the cash with cause I aint had any.
Plugs were totally rooted and melted, was low on oil, afew vaccum lines were cracked and leaking to. The breather hose from the cam cover to airbox was kinked real bad aswell and timing needed to be adjusted. Not sure if the shudder is sorted or not cause I have not picked the car up yet. But have been told the engine is not the healthiest so a rebuild or replacement is the go.
Oh and the manifold needs to be machined flat aswell which will be for a later date.
 

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