Here's one of my injectors

[victorviking]

It's out of my '69 911E that has been sitting for 25+ years (until recently).







I'm not sure how much spray should come out of one of these when it's clean but I've ran some compressed air to it and it seems hopelessly clogged - nothing coming out of it. I let it sit in fuel injector cleaner for about two weeks with no result.

I've looked on this site but haven't seen much on this type of injector. Is there anything else I can try? I'm trying to clean everything in the fuel system before getting to the MFI pump - fingers crossed.

[RWebb]

send it to a facility that cleans these commercially

IIRC, they often use ultrasound

[Flat6pac]

You need to put it on a diesel injector check that uses high pressure to force say kerosene yjrough the injector to show the spray pattern. 100psi air pressure wont do it.
Bruce

[victorviking]

Thanks Bruce - will most diesel mechanics have that tool?

[zippy_gg]

Try these guys, they are good: WitchHunter Performance - Injector Cleaning & Flow Testing Services
I sent the injectors of my A4 V6 and they came back perfect, along with a before and after performance chart.

[Flat6pac]

any diesel shop should have it.
Bruce

[tharbert]

The MFI injectors are considered high pressure for gas systems. I think they open at about 170 psi so your air compressor probably wont have much effect.

Cleaning procedures I found here say to soak in Berrymans and clean ultrasonically. They are neither repairable nor rebuildable but, as they are mechanical, they are fairly robust. If on a budget, consider just giving them a cursory inspection for obvious physical damage, clean them up, and reinstall. They run about $170 new and used are avaialble in the parts forum occasionally.

[paulgtr]

where are you located? I did a search for fuel injector shops and found one near me. dropped them of and had them flow tested and back to me in a couple days only cost 25 dollars per injector and they worked like new.

[victorviking]

Originally Posted by paulgtr

where are you located? I did a search for fuel injector shops and found one near me. dropped them of and had them flow tested and back to me in a couple days only cost 25 dollars per injector and they worked like new.

I'm in Phoenix, AZ.

So it sounds like I shouldn't be getting any type of flow out of these injectors unless I have more pressure to them - Could it be that they're not clogged after all?

[tharbert]

Originally Posted by victorviking

I'm in Phoenix, AZ.

So it sounds like I shouldn't be getting any type of flow out of these injectors unless I have more pressure to them - Could it be that they're not clogged after all?

Basically, yep. They me be just fine. As I said, these injectors are fairly robust.


There is a procedure called CMA - Check, Measure, Adjust associated with MFI. Do a search! One of the steps in this process is to determine if the injectors are OK. So, I suggest you get the engine running. Then, if you have performance issues, start CMA.

[al lkosmal]

Diesel Injector Tester Mercedes 190D 240D 300D 300SD : eBay Motors (item 380186556699 end time Feb-07-10 09:43:49 PST)

I bought one of these. The gauge on this is calibrated for diesel injectors, but is easily replaced with a more appropriate pressure. The injector fitting is correct for Bosch mechanical injectors. I used mineral spirits to pump through the injectors.

PS: no affiliation to the manufacturer of these, they just happen to be close by, so I drove up and bought one direct from the company.