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I am new to common rail. I know VW TDI ALH engines and PD but not these fancy electronic piezo injectors.
My 2007 E320 OM642 kept getting harder and harder to start. I changed the fuel filter and found some water in it and the codes also showed water in fuel. Changing the filter didn't really change much.
I still had problems with the car not wanting to start. This went on for about 6 months. "keep in mind" I don't use this car much. I am shocked if I put more than 3000 miles on it a year. Maybe 1000. It is not uncommon for the car to sit a month in between starting. I have a European hitch on it and use it more like a pickup than a car.
It has sat for about a year now and won't start at all. It will stumble a little and smoke but not run. I checked the fuel filter again and there was water again.! I had only put maybe 500 miles since the last fuel filter. I was an idiot. I should of not just changed the filter but purged the entire fuel system. I rebuild injectors for VW ALH engines. Two-stage pop.. so I decided to tear these down. The insides of the injector bodies looked ok. No rust. There was no rust on any of the fittings or connections to the common rail. I didn't see signs of water damage at all. However, the nozzle's spray patterns were awful. Using a can of carb cleaner to see the pattern half would not spray at all, Two out of one hole, and one out of three holes. I did an ultrasonic clean-up and tested again and I had a nice clean pattern on all nozzles. I could not pop-test these. I use a mechanical hand pump to pop VW injectors. That would not work on these. so the extent of my testing was the nozzle and carb cleaner.
I put them back together in the exact same order in the exact same bodies and in the exact same holes. Now the car won't even stumble or try to start. I can use starting fluid and get it to run but it is running off starting fluid only. I bled the system like I do a VW by losing all the injector bolts until they all leaked diesel then tightened it back up. I tried several times no start. Then I cracked the line from the common rail pump and it didn't spray any harder than with just the lift pump running during starting. So I pulled a injector out of the hole and aimed it in the air and tightened it back up. Started again and watched for a spray pattern.... Nothing. no fuel noting. That would explain my "no start problem"
so... Do I have a purge issue on the common rail? Air trapped somewhere? Or do I have a common rail pump that is bad? These are the fault codes before I pulled the injectors to begin with. RIght now the car does not start so I really don't get any codes. I cleared everything.
Last edited by rpallesen; Sep 15, 2023 at 05:32 PM.
Those are all stored codes, who could happen a year of more in the past.
Clear them and recheck. They look to me like mostly result of low battery cranking.
Are you the 1 who made the topic about cleaning the injectors and reinstalling them without testing and coding?
That is me. I cleaned everything up and checked the spray patterns and put it all back together. Now it won't even stumble or try to start. With a injector pointed to the sky it does not spray one bit. The battery was the original battery from 07 and it was getting a little tired. So I put a new one in.
There was one point of question when I tore down the injectors. I didn't notice the little metal seat on the little spring in between the valve plates. So when I was putting them back together I realized there was a metal needle on the spring. After looking at diagrams I decided the needle pointed away from the tip of the nozzle and toward the inlet side. It is possible I put these back together wrong. If anyone out there knows these injectors please chime in.
See item #7 control valve.
Last edited by rpallesen; Sep 15, 2023 at 05:43 PM.
Like I said in other topic, putting DIY rebuild injectors without proper testing and coding is high risk procedure.
You still should read the rail pressure. So clear the codes, make double sure they are cleared and run live data on rail pressure during cranking.
If I remember correctly, you should have in the range of 4000 psi for the engine to start.
This valve assembly is also a pint of wear that requires lapping and special tools to recalibrate. Or people just buy new ones in a kit. I would assume that wear does not cause leaking but reduces fueling based on how it works. As the surfaces wear down the needle is open for a shorter period of time.
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