The Protege has about 130k on it and I'm thinking of sending the injectors off to be professionally cleaned. Cost is about $100, give or take. Do you think professional cleaning is worth the expense or should I just run some Seafoam with my next few fill-ups?
It is worth it. Find a local place though and you can actually watch them do it, and usually for cheaper. If one or more is unable to come up to specs with the others it will also give you chance to buy a new one or have more tested from a JY.
You can build a DIY setup really cheap that will be just as good. Just get an old intake manifold/fuel rail and hook up a mock fuel system with an old fuel pump and gas can, put your injectors in the manifold then run some parts cleaner through the system (you can just put 12v across the injectors to open them up, unless they're low impedance in which case you need to pop a resistor box in there). Works great. I've cleaned really crappy old injectors with this method and they flow like new afterwards.
If you don't have the parts, you can probably get everything you need from the local pull-a-pat for $50 or less.
If you want to get real fancy you can even hook up some circuitry to pulse the injectors. We used an old MS ecu and a stim board to pulse some really cruddy injectors at Wreck Racing.
We sell ours for $138.00 after tax. I personally think it is worth every penny. My boss freaks out because I don't sell the rest of the programs but I sell fuel and brake services.
One thing I discovered with sending injectors to an inexpensive cleaner is that they used really cheap replacement rubber seals, which deteriorated pretty quickly, causing all sorts of fun but difficult-to-find vacuum leaks (and, under boost, fuel was getting blown out under the hood!) 
They also re-painted the injectors with some cheap-ass paint that disappeared pretty quickly; I would've rather had the original, somewhat worn paint that Bosch sprayed.
RC or Witch Hunter are the two services that come first to mind. I was planning on sending my set from the bmw out to them some time in the near future.
JohnyHachi6 wrote: You can build a DIY setup really cheap that will be just as good. .. .. . . . . .
Hummmmm I have all those parts in my basement. What solvent / cleaner would you recommend? Lacker Thinner, Acetone, MEK. Redline EFI cleaner
You can just get a couple resistors from the local electrical store similar to those I used for my MS project using low Independence injectors. I think they were somthing like $5 each new
These are the ones I am using at the moment.
Thanks for the input, everyone. I think I'll go with a DIY approach like JohnyHachi6 suggested. Thinking of getting some graduated cylinders to measure before and after flow, too.
Anybody got a pic of the DIY settup? This is something I'd love to learn about, but have zero electrical competence. Willing to learn though.
you used to be able to buy a can of stuff that you hooked up to the fuel rail. you jsut pulled the fuel pump fuse and let the car idle on that can until it was empty.
one of my neighbors did it to his daughter's late 80's Escort GT and it totally changed the way the car ran. of course, this was like 20 years ago, so the stuff probably got outlawed for being too cheap and easy..
i just run a bottle of Mavel Mystery Oil in an almost empty tank of gas once or twice a year. a big bottle is under $2 at Wal Mart and it must do something because i always gain a couple of mpg after doing it.
I was reading somewhere recently (prob turbobricks) to put power to the injectors and spray carb cleaner fluid though the bottom tip of the injector... not as elegant as hooking up the old fuel system... but they said it worked well
donalson wrote: I was reading somewhere recently (prob turbobricks) to put power to the injectors and spray carb cleaner fluid though the bottom tip of the injector... not as elegant as hooking up the old fuel system... but they said it worked well
I've done it. It worked GREAT.
Wear safety glasses...that E36 M3 hurts when it sprays back at you.
so basically you just open them up and spray carb cleaner?
from what I read yes... but from the spray/piddle end not the fuel rail side...
donalson wrote: from what I read yes... but from the spray/piddle end not the fuel rail side...
I think the biggest effect this has is cleaning out the screen / filter at the inlet. If it is clogged this is a very good way of cleaning it out short of taking it apart. It would have a huge impact on the injectors performance if it was clogged or partially obstructed.
As see in this image.
I thought the filter screen at the inlet on most top fed injectors were easy to replace. But I've never done it; has anyone here?
FWIW, I've used Berryman's on carburetors and fuel injectors with excellent results. The can of the stuff you just dump in your tank. On those vehicles that I've obtained with many miles on them, it usually made a substantial change in how they ran.
I've gone behind it a number of times on carburetors, and always found the bowl and lets to be sparkling clean, with no varnish or gum. Chunks of dirt, grit and filings of course do not dissolve.
I read somewhere that a little 9V battery worked great for injectors, but I have no first hand experience of this.
This may sound like a commercial.. Take this for what its worth but Marren Injection cleaning got me back 99.8hp on a dyno. To my that was well worth the $115 it cost me. to clean 4 injectors and ship them back.
My Dwarf had been slowly getting slower and slower then it would not pull at all over 5000rpm I had cleaned the injectors twice myself, swapped computers 4 times, changed crank pick ups, changed camshaft pick ups, changed wire harness... Gave up and spent some $$ on a dyno run. It showed way lean even with 43psi 6 inches before the injector rail. So I sent the injectors to Marren and got them back in 4 days with new O-rings. Back to the same dyno (lucky for me the weather was the same) and we went from 33hp to 132.8HP and it would pull to red line.
Don't bother to waste your time and DIY send them to a place that is 100% injector service, it's not a side job or a product line for them its all they do.
No I don't work for them, I get no $$, no sponsorship etc.
44Dwarf
I cleaned a particularly nasty set of Bosch CIS injectors myself. I was actually able to bring them back into spec for flow rate and pattern. Not really the same as electronic injectors but it worked out fairly well. I let them soak for 24hrs and alternated between back flushing and regular flushing at very high pressures using seafoam. Worked surprisingly well.
novaderrik wrote: you used to be able to buy a can of stuff that you hooked up to the fuel rail. you jsut pulled the fuel pump fuse and let the car idle on that can until it was empty. one of my neighbors did it to his daughter's late 80's Escort GT and it totally changed the way the car ran. of course, this was like 20 years ago, so the stuff probably got outlawed for being too cheap and easy.. i just run a bottle of Mavel Mystery Oil in an almost empty tank of gas once or twice a year. a big bottle is under $2 at Wal Mart and it must do something because i always gain a couple of mpg after doing it.
A mechanic friend was just telling me about this stuff. Anyone have knowledge of current availability?
edit: the fuel rail stuff, not the Marvel Mystery Oil
www.injectorpulse.com
NASA Mid Atlantic member, good guy. I get nothing forrom him, but know many satisfied customers. I also know him, and he's grassroots material. Also, he could use the money to rebuild after totaling his race car recently.
Definitely worth it. I sent the injectors from my 90k Miata out for testing and cleaning. Turned out two were dripping. Got them back and car feels peppier and gets a little better MPG.
RC Eng, Marren (aka injector.com), WitchHunter are all good sources with good test equipment that use quality components in the rebuild.
Similar experience to mine - I had Marren clean a couple of sets of NB injectors for the Miata and it did run better afterwards. Plus, they also check for and will tell you if one or more are out of spec even after they've been cleaned.
Just my opinion. I am older than most on this site, always do my own maintenance on both my wife's and my own car. We put over 35k miles on our cars each year. I have been driving EFI cars since they came out and have never once cleaned or had someone else clean injectors. Never had one go bad. I don't think it typically does any good.
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