Stutter, Stop, Bang at the back

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srmalek
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Sun Feb 06, 2011 4:15 pm

Hi my 323i 1985 m20 just develop a new problem apart from the central locking and the autobox (both fixed)

ok here how it happened

I was driving my e30 one afternoon and love its acceleration and keep on flooring the pedal, then suddenly a big bang came from the back of the car and it stutter and stop, manage to start her up again and the exhaust sound like a racing exhaust,

When i got back home i could see the back of the back exhaust rip about 12 inch, and since then the engine will die when i accelerate the car and sometime it takes me up to 4 - 8 attempt cranking to get her back.

so could the rip exhaust be the source of the stutter and dead engine? before this i could smell strong fuel coming from the exhaust but no white smoke.

thank you
SAMB0
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Sun Feb 06, 2011 9:35 pm

Sounds like excess fuel ignited in your exhaust. I split an exhaust open not long ago floored my girlfriends vw polo and boom! turns out the baffle was blocked from the centre silencer rusting inside, breaking up and clogging the back box. Pull the spark plugs out look at the end of them they should be a light brown/tan sort of colour if it's running well. If they're black it's running too rich. Probably worth changing them anyway for the price.
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srmalek
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Mon Feb 07, 2011 6:46 am

SAMB0 wrote:Sounds like excess fuel ignited in your exhaust. I split an exhaust open not long ago floored my girlfriends vw polo and boom! turns out the baffle was blocked from the centre silencer rusting inside, breaking up and clogging the back box. Pull the spark plugs out look at the end of them they should be a light brown/tan sort of colour if it's running well. If they're black it's running too rich. Probably worth changing them anyway for the price.
Thanks for the info sambo, yeah i presume the engine is running too rich from the strong smell from the exhaust, ok will check the plugs later but anyway does the rip exhaust can cause the engine to stutter and stall everytime i accelerate? what i have being told that the exhaust system for e30 is very sensitive
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srmalek
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Mon Feb 07, 2011 12:39 pm

bump
Ilkorin
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Mon Feb 07, 2011 12:56 pm

I'd say it's more likely the engine is stuttering when you accelerate because of some mixture issue! It's hard to say if it's too rich or lean just from the performance and the smell, because if it is too lean you get a misfire and the fuel in that cylinder is pushed out without having been burned.

I don't think the exhaust is too sensitive to holes near the back, although if there is a hole near the lambda sensor that can play havoc with the fuelling
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srmalek
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Mon Feb 07, 2011 1:20 pm

thanks Ilkorin so what do you suggest me to do it it mate? any checklist suggestion?
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Brianmoooore
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Mon Feb 07, 2011 7:17 pm

Difficult to say what's wrong until the exhaust is sorted.
Whatever caused the explosion could be the same thing that's killing the engine, or the explosion may have blocked the exhaust as well as split it, and this could be killing the engine.
You definitely had a whole load of unburnt fuel mixture in the exhaust system which suddenly detonated, but there's no clues as to why yet.
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srmalek
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Wed Feb 09, 2011 2:03 pm

Brianmoooore wrote:Difficult to say what's wrong until the exhaust is sorted.
Whatever caused the explosion could be the same thing that's killing the engine, or the explosion may have blocked the exhaust as well as split it, and this could be killing the engine.
You definitely had a whole load of unburnt fuel mixture in the exhaust system which suddenly detonated, but there's no clues as to why yet.
did replace and checked the exhaust system today, but the killing to the engine still happen, could it be the fuel pump playing around, because not only during accelerate but when i switch from P to D it kill the engine as well, but sometime it went fine . why? 8O
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Brianmoooore
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Wed Feb 09, 2011 2:12 pm

From what we know so far, it could be one or more of many things that are wrong.
Start by carefully checking out the large convoluted air hose from the air meter to the throttle body for cracks and splits.
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srmalek
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Wed Feb 09, 2011 3:27 pm

Brianmoooore wrote:From what we know so far, it could be one or more of many things that are wrong.
Start by carefully checking out the large convoluted air hose from the air meter to the throttle body for cracks and splits.
ok thanks for the tips sir, will check it first thing tommorow
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srmalek
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Thu Feb 10, 2011 5:01 pm

srmalek wrote:
Brianmoooore wrote:From what we know so far, it could be one or more of many things that are wrong.
Start by carefully checking out the large convoluted air hose from the air meter to the throttle body for cracks and splits.
ok thanks for the tips sir, will check it first thing tommorow
done with the air hose etc, no crack splits or air leak sir, what shd i check next?
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