bad injector?

[The Radium King]

so, looking at my durametric manual (at work) it looks like i can individually turn off injectors to force a cylinder misfire. theoretically then, if my injector was stuck open and causing my symptoms, then turning it off with my durametric should have no effect - i should be able use the tool to isolate the problem injector (all the functioning injectors would cause a misfire when turned off).

if that is the case, how often do injectors fail? i ask because one new injector on pelican is $300, but i can buy six used ones for under $100 on ebay ...

[BYprodriver]

Undoubtably they all need to be cleaned & tested & replaced if faulty, so that would give you the best final result.

[The Radium King]

yeah. i'll try my test tonight. if it yields results i'll repalce all of the little basturds. any recommendations on non-oem replacements that might be a little less expensive? bosch is bosch, right?

[BYprodriver]

Originally Posted by BYprodriver

Undoubtably they all need to be cleaned & tested & replaced if faulty, so that would give you the best final result.

I was talking about out of the car cleaning at a speciality shop like the one I use in Torrance CA : rceng.com

[The Radium King]

i live way out in the sticks, so options are limited. hoping to run a test with my durametric (and some of the other tests out there - measure resistance, etc.) and see if i can get an easy answer that way. if the injector is the obvious culprit then i am faced with replacing all or just the bad one, as my car would be out of commission for a month if i sent mine out to be tested/serviced. at $135 for a bosch unit (as opposed to $300 for the porsche product) i might want to do all 6 just to be safe, but if they rarely fail mebbe i just do the bad one(s).

[Gilles]

Originally Posted by BYprodriver

I was talking about out of the car cleaning at a speciality shop like the one I use in Torrance CA : rceng.com

1 + on RC Engineering,

Quick turn around time and for the price they charge is a bargain, you will love the way the engine runs afterwards..

.

[The Radium King]

well, good news and bad news. good news - my car is about to get a lot faster. bad news as follows:

logic. have p1128 which is bank 1 to 3 too rich. if it was p1128 AND p1130 (bank 4 to 6 too rich) i'd think issue with maf. with just one bank having trouble it's either an 02 sensor or something with the air and/or fuel supplies.

check my oil - smells of gas. this may be a result of an injector stuck open. when the car sits, it dribbles gas into the combustion chamber, which then leaks past the rings into the oil. in hindsight, it may also be a cause of the smoking i see on start-up - rich rich rich fuel getting pumped out the exhuast.

so, thinking injector issue.

start engine, connect durametric.

knowing that i have p1128 which is bank 1 to 3, i start on bank 4 to 6 to get a benchline.

using the durametic to turn off individual injectors, i can feel the engine start to run rough every time i turn an injector off. cool.

going to bank 1 to 3, turning of injector 3 gets the rough running condtion. good. unfortuately, it looks like both injectors 1 and 2 are bad, as turning either 1 or 2 off gets no effect.

so, looks like i'll pull all 6 and send them out for refurbishing. RCEng looks the ticket; thanks for the help guys. also time for an oil change - want that gas outta there.

[jaykay]

Awesome job! I actually didn't know you could easily turn off injectors via Durametric....thought one needed the professional version. I will be getting this software set up soon....don't see a manual.

Good catch on the oil!

[JFP in PA]

Originally Posted by The Radium King

if that is the case, how often do injectors fail? i ask because one new injector on pelican is $300, but i can buy six used ones for under $100 on ebay ...

Injectors do not fail often, but when they do, you need to either have a reputable shop retread them, or buy new. I really would not be comfortable with buying used injectors off flea bay, you have no idea what shape they are in. I'd also suggest giving Sunset Porsche in Beaverton, OR a call for new unit pricing.