firelikeiy

HI, I have a 2008 IS250. I'm in the process of replacing the motor. I ended up taking the fuel injectors out to replace a coolant pipe and decided to do a DIY fuel injection cleaning. What I used was a 12v battery to open the fuel injector and I rigged up some fuel line with a can of spray carburetor cleaner as the cleaning solution. 5 of 6 of the fuel injectors had a mostly fan pattern to their spray but one of the fuel injectors had 2 streams coming out roughly 45 degrees apart. I do not know what the normal operating pressure of the fuel injectors are but I am guessing it is around 2,000 psi or so while the can of carb cleaner would only be around 200 psi. I called a couple of shops in the area that do fuel injector cleaning. I spoke with one that does not do high pressure DFI injectors but he told me that since the pressure I was working with is so much lower than normal operating pressure that it is hard to say whether or not what I saw is actual spray pattern. I found only one shop in the area that does DFI injectors but they are an hour drive each way. They have a 4 day lead time to clean the injectors and will charge $150 to do it. I'm kind of in a rush to get this car back together. It's a used JDM motor and only came with a 60 day warranty. I believe I am almost out of time to get the engine installed and running to see if the motor is good. Would it be worth the time to have the injectors clean? If I get the injectors cleaned it will push me beyond the warranty period because I wouldn't be able to work on the engine for another week or so due to work. Any opinions?

MikeFig82

iTrader: (13)

Maybe try to back flush the one injector for awhile. Then normal flow to see if the pattern changes. The injector has the filter on inlet side from fuel rail. If no change then the injector has probably failed internally.

While flowing it I wouldn't do more than 3 seconds to power it. Probably 2-3 seconds burst holding voltage to open is ideal. As the ecu controls PWM you'll never see it spray in automation.

firelikeiy

I tried to backflush it a bit but there wasn't much change. I'll try again tomorrow morning. 5 of the injectors on my old motor are still good but they have 182k miles on them. I'm guessing the JDM engine has 90-100k. Probably wouldn't be worth using one of the old injectors, would it? I only checked one of those but it seemed to have decent flow. Resistance was 0.1 ohm higher on it though.

MikeFig82

iTrader: (13)

Not many failures reported on injectors. If reusing you should use fresh set of orings. That way you avoid any possible leaks.

I myself still thinks I'm dealing with 2 leaky injectors at the moment. At this point I haven't decided to take the car apart to check.

firelikeiy

Well, I went ahead and had the injectors professionally cleaned. The shop told me that they see very few of our injectors and that they are some of the better ones out there. I'm glad I had them cleaned. They said it was quick to match the flows but it took a while before the spray pattern was good. The spray pattern was so bad on one of them (3rd from left) that I am amazed that they restored it to like new. They never gave me an official printout, they just emailed me these pics, but it looks like they got them within 2% I took them to AUS Injectors in Tempe AZ. They originally quoted me 3-4 days but had them done the next day. Awesome service.