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Discussion Starter · #1 ·
a friend of mine that breaks m5's says that the injectors are a weak spot in the motors. he said that the center "t" that divides the injectors into 4 small holes often breaks, turning the injector into solid stream hoses instead of the intended misters. This makes the O2 sensor think the whole engine is running wicked rich, so it leans out the good injectors causing motors to go ka-boom.

anybody hear of this problem? I don't like ka-boom's so i was thinking of replacing these for keeping peace in my mind

thoughts?:1zhelp:
 

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Well, there's a business out West in the US called Cruzin Performance, that rebuilds injectors for very cheap. Rebuilds, flow-tests, etc. and supplies before/after information.

Unfortunately for you, they're out here, but if you're interested. LOTS of MyE28.com users have used them, and I've used them twice with very good results.

http://www.cruzinperformance.com/
 

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Discussion Starter · #3 ·
that's good and well, but my friend was saying that he has seen 2 engines 3.8L's fail with rebuilt injectors. seams that there is fatigue in the plastic, something that rebuilt injectors doesn't deal with.

rebuilt injectors are basically cleaned in "special" solvant to remove any gunk and new gaskets/rubber installed correct?
 

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that's good and well, but my friend was saying that he has seen 2 engines 3.8L's fail with rebuilt injectors. seams that there is fatigue in the plastic, something that rebuilt injectors doesn't deal with.

rebuilt injectors are basically cleaned in "special" solvant to remove any gunk and new gaskets/rubber installed correct?
You're correct, mostly.

Their website explains their process in a little more detail...

http://www.cruzinperformance.com/injsteps.html

They are replacing the inlet screens, along with the gaskets/O-rings
 

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The 3.8 injectors are ofcourse different from the 3.6 ones.

The 3.6 ones respond well to ultrasonic cleaning, whilst the 3.8 items (I think those are Bosch where the 3.6 ones are Lucas, or the other way around :D) can't be helped beyond replacing the attachment rubber rings. Could be a thread to the engine , but as far as I've heard its not very common compared to other engine failure causes.
 

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The 3.8 injectors are ofcourse different from the 3.6 ones.
Correct, and the B38 injectors need regular replacement to avoid 'pissing' injectors.

Could be a thread to the engine , but as far as I've heard its not very common compared to other engine failure causes.
Not true, although there are no statistics to proove, I know that many B38's suffered from molten pistons due to injector failure. In fact, this is the most contributing cause to the 'myth' about the B38 being less reliable then the B36. But if you change the injectors around (a ball park figure) the 120k km mark, you might be safe. A well known 'See You' registered M5T is proof of that. The problem is that six new (Lucas) injectors for the B38 cost close to a grand, which again is a bargain basement compared to those of teh MB M100.981 engine were a grand is not even enough to obtain one injector.
 

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Discussion Starter · #8 · (Edited)
dallas - where did you source those bosch injectors? what did they origionally come from?

real OEM showes the lucas injectors being $42 plus a core.

I'll stop by the local BMW dealership today to see how much they differ from real OEM
 

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dallas - where did you source those bosch injectors? what did they origionally come from?

real OEM showes the lucas injectors being $42 plus a core.

I'll stop by the local BMW dealership today to see how much they differ from real OEM
I've simply bought them from ebay. 200$ - six new injectors.
Local dealer asked 300$ (or 400$ i don't remember exactly) per injector :1zhelp:
 

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I wonder if any of these would be applicable?

http://www.fiveomotorsport.com/Injector_SetsBMW.asp

Obviously, being an American based company they don't mention B38 equipped cars.
I have installed these :

http://www.fiveomotorsport.com/Injector_SetsMODS.asp#bosch19

30# red tops

Nobody lists injectors for B38 because original Lucas injectors size is unknown. It is somewhere in 280-290-300cc range.

These Bosch injectors are rated 300cc (315cc from some sources).

However I want to mention that my car is running a bit rich when cold. when it warms up - OK. I think it is because injectors a bit bigger and when engine becomes warm - lambda starting it's corrections (Please correct me if i'm wrong)
 

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Concerns of overich mixture from cold start would be with close coupled
Ceramic monolith cored cats.
The metalised B38 cats are more durable though are slower to reach optimum
operating temp.
Our cars do not have close coupled cats.:)

Other issues if mixture at idle dwell does not clear is bore wash, a common
problem with large injectors not mapped to optimum.

My Lucas B38 injectors have seen 183k miles with a clean @ 120k miles
The car passes VOSA idle / fast idle with middling water & bulk oil.
(Its overfuelling slightly from cold which is worn nozzle spray pattern I suspect)
 

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Concerns of overich mixture from cold start would be with close coupled
Ceramic monolith cored cats.
The metalised B38 cats are more durable though are slower to reach optimum
operating temp.
Our cars do not have close coupled cats.:)

Other issues if mixture at idle dwell does not clear is bore wash, a common
problem with large injectors not mapped to optimum.

My Bosch B38 injectors have seen 183k miles with a clean @ 120k miles
The car passes VOSA idle / fast idle with middling water & bulk oil.
(Its overfuelling slightly from cold which is worn nozzle spray pattern I suspect)

Thanks farrel.

Cats were modified by previous owner (hello Jahangeer! :)) - only 1/3 left.
I definately need UNICHIP remap for bigger injectors.
Btw i can really feel difference with these NEW bosch injectors - old were tired IMHO.
 

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Discussion Starter · #15 ·
Real OEM lists Lucas as the manufacturer for 3.8L and Bosch for the 3.6L. are you sure yours were bosch?
 
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