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Hello, im a new 155 driver & come from Malaysia

Last week... my 155 engine explode like a bomb while starting my engine (cranking)... my inlet manifold (sign TWIN SPARK)... crashed !!!

one of my friend told me cause of spark plug... i use a Bosch Super 4, he said... that one is not suitable with 8v TS engine...

then, i replace a 2nd hand inlet manifold & a spark plug (Golden Lodge for TS engine)... the Bosch plugs head 1.5mm longer than the Golden Lodge one... dunno what will happen again...

the problem come again... but not everytime i start my engine.... its very seldom...

one foreman told me... my flywheel (rpm) sensor... but my foreman said... if flywheel sensor problem... my idling getting worst & engine hard 2 start... but, my engine idling very good !

replaced a flywheel (rpm) sensor... still face the same problem...

then, my friend told me... cause of my timing chain... it loose... so, when the bad time i stop my engine... there are 1 or 2 valve did not close perfectly... so got backfire inside the head & come out trough my inlet manifold & bomb !!! & crash it !

somebody told me, there are plug coil problem... but i've check them... still ok !

please healp me... i dun have any idea....
 

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Make sure the Bosch plugs are the correct ones for your engine. Some plugs have a projecting nose (the centre electrode sticks out past the end of the threaded part) and if you have these in your engine but the engine isn't designed for them then you'll risk the plug hitting the piston.

Look in the manual and see what plugs it recommends for your 1.8. Do those plugs have a projecting nose (NGK type have the letter "P" in the designation e.g. B P R7ES)?

If your Super-4 plugs are the same physical size as these recommeded plugs then they'll be okay (the crucial difference is how far the electrodes stick out after the end of the threaded part.

The plugs also have to be the correct heat rating for your car but that's a different question and it won't necessarily cause the problems you are describing, if you have the wrong heat range of plug. What do the plugs look like? If they look very white or heat damaged, they MAY be the wrong heat-range..

If you have a new crank sensor then that's not the problem.. It might make your car harder to start and idle roughly but it might just fail without warning. Anyway, you have a new one now.

If there is any chance that your timing chain is loose then that's the place to look. Make sure the timing belt is properly adjusted and that the valve timing is correct. It sounds like your valve timing is out... even one tooth will make a difference.

It COULD be the coils but start at the timing chain.

Ralf S.
 

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It seems the 8v 1.8 needs a BP6E plug (in Britain at least, Malaysia is a bit warmer, so a BP7E might be an alternative). I think the Bosch Super 4 fitment is a number ?? 56.

Anyway, both these types have a projecting nose.

Golden lodge don't have the outer "hook" electrode - just 4 little "blade" electrodes next to the centre. Don't worry that your Bosch/NGK/Champion plug are different.. it's just a peculiarity of the Golden Lodge plugs and is "normal".

Ralf S.
 
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Discussion Starter #4
just change a new empty engine (used one) 2.0 8v - 16k milage at rm2.8k price... (usd 750)

everything settle... !!!
speeding 200 - 210kmh very smooth & low noise engine

tq everybody
tq uncle steven saw &
tq too to bro nahar penang
... tengkiu very much...
 
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