Fuel injection system purging/ultrasonic cleaning. Are we nearing an end?

lendaddy · 05-01-2002, 09:19 AM

I pulled my injectors last night and let them spray into aerosol can tops. It took a while for some of them really start spraying and even when they did the looked kinda fugly. So I yanked them out and plugged the holes in the intake with upsidedown wire nuts. I found a place in town (diesel place) that will clean and test them for me by 5 P.M. so I will have them in tonight and all should be well. Anyway I have a question, When I put them back in I will "purge" the system again. However once they are purged I will have to remove or atleast loosen them from the lines again to install them in the intake. Now won't this create another air pocket in the line? I am assumeing that it is so small that it wont matter. Should I leave the lines lightly attached while I thread the injectors into to intake or not, I would assume so as it would atleast limit the fuel draining back out of the line to a minimum. Thanks again guys..

P.S. If anyone knows if our tachs are voltage or amperage triggered thatwould be very helpful.

Superman · 05-01-2002, 11:08 AM

As I recall, you have the Ultimate Porsche (late model SC) with hard fuel lines. Wise choice. No, you don't have to put injectors on twice. You should have a popoff valve in your air box, though.

Just pu the injectors in their homes, connect the fuel lines and bleed the system quickly. That is, turn on the ignition and manually raise the air flow sensor plate. Within seconds, you will hear the injectors making that singing noise that they make. STOP. If you're nervious, you'll wait just a littel bit. If not, just start the car.

Of course, if you want to see whether your injectors are spraying better now, then you will have to use the aerosol cans again.

Joeaksa · 05-01-2002, 11:13 AM

Let us know how it turns out. The injectors on my 85 model are orginal and wonder what the spray pattern looks like on them!

How much did it cost and so on? Really interested to see if the car drives better after cleaning them and if it does may do the same thing to mine!

Joe

lendaddy · 05-01-2002, 11:24 AM

I will certainly post my results. I am sure every town has a diesel injection service place that can do this for you. They cleaned and tested them. They just called and said they are now perfect. The tab for this was $96.61 for all six. Sure beats $420-$600 for a set of new ones. Mine were original That means 105,000 miles and 25 years of service and still ticking. I will talk to the tech when I pick them up but to me there was an obvious difference in the spray on each of them when I did my little test.

lendaddy · 05-01-2002, 11:27 AM

Oh yea, I came up with a better way to check the spray pattern than what I posted earlier. I went to a hardware store and bought 12' of clear large diameter vinyl tube I will put the injectors in a 2' length of this then route the other end to a resevoir. I think this will allow me to watch the spray pattern and keep the gas from spraying all over the engine. This is acually getting kinda fun.