So this one may turn out a bit comedy more than anything. Maybe, just maybe. I went through some stuff this evening but now thinking it was all pointless. In fact the car may be able to start right now with a good charged battery and a jumpered vehicle running giving it some revs. I've had this issue before with my previous car sitting after doing some work on the turbo. I completely forgot that if these cars sit for a while, the fuel system can drain back enough that it won't start. Then it starts to throw a low oil pressure while cranking light which is really scary. That popped up on me last night but it didn't really dawn on me until googling what I can do to fix it. I may have inadvertently caused the low pressure on the fuel rail tinkering with stuff which sent me down a rabbit hole. Also being told it was an injector problem I just assumed they knew what they were talking about.
After I got home from work I was able to initiate a text conversation with the previous owner. He went on to tell me he took a RUNNING DRIVING car in to the shop to get work done on the A/C system!!! I don't know if they had trouble with that or it sat for a bit but I think that's why it stopped running in the first place? I still plan to contact the shop to get more information but I thought it was crazy he brought in a running driving car and they gave him back one that no longer does any of that. He also said the flywheel was making some chatter. That stinks. I replaced one on my previous A3, it wasn't hard but it still wasn't fun either.
So before figuring out all of that I couldn't wait to pull the injectors. I'm very impatient. After cleaning up the area where they bolt in I took each one out and looked them over. Nothing obvious problematic about them but the tips were bone dry. Definitely not getting enough pressure to get them to fire. I set them up with some cups to catch fuel in hopes there was a spray pattern to see but nope. Wasted time. No spray was achieved.
Tomorrow morning I plan to re-install the injectors. I'll still order new o-rings and seals if this thing fires up. I also plan to do more extensive flow tests with the lift and aux pump. The aux pump was aerating fuel when using the prime setting and seemed to cut out with OBD Eleven. I think that had more to do with the filter basket going empty and possibly just not a great connection with the bluetooth where I was standing. I need to run the in tank pump while trying to run the aux. That's the first test. Then I plan to hook up the Jeep with jumpers and cross my fingers that it's just needing a good jump to get running again. If not I'll keep plugging along chasing my tail and report back.
Haven't got started yet but read this when I woke up. I've read over it before but sometimes it's hard for me to focus on the details vs the overall. Also most repair or troubleshooting threads overflow with useful information to digest. Basically if the jump start doesn't work then it can be narrowed down to the aux pump which seems to be likely or the fuel regulator valve. Going to clean the regulator valve if the aux pump flows well enough.
The vag Self Study Program 840193 indicates only the fuel pressure regulator valve on the end of the rail and the auxiliary pump can cause no start. The valve in particular if it fails to close properly will leak the pressure in the rail needed for the injectors to fire. The HPFP fuel metering valve, and the pressure sensor will at most cause slow running or limp if they fail. Very useful read.
https://vwcampersite.wordpress.com/wp-content/uploads/2015/01/ssp_826803-20tdi-common-rail-bin5-ulev-engine.pdf
I got good news and I got bad news.
Good news is I think the aux pump is on it's way out or has a restriction from the fuel filter inlet.
Bad news is, it was fricking hot by the time I got out there. Only 80 degrees out but I was in direct sun with 80 percent humidity. I was also in my work clothes which was about a good of choice as drinking milk before hanging out in a sauna.
Anyway, I attached a motorcycle battery sending direct 12v to the in tank transfer pump so the aux pump had ZERO excuse to not flow fuel properly. With the transfer pump humming along the aux pump still spit out aerated/foamy fuel. Also not near as much as it should when triggered. I would consider a deadhead test on it if I can find one of my gauges but it should read ~73psi. The in tank pump should be roughly half or so I think? Can't find the exact number for it right now but it flows easily twice what the aux pump does with zero foam which makes me think it's good to go in this situation. As mentioned in my last post there's really only two things that should cause a full no start condition. Aux pump or the fuel metering valve at the rail. It feels like I got my answer?
So I started cleaning up the injectors a bit with a quick wipe down and then cleaning the mating surface/bore for them to be installed. It took a while to get them all clean so I had just enough time to start installing one injector. When I went to tighten down the two 10mm nuts I realized I never looked up the torque spec. So that's when I called it quits. No sense rushing this, I'll pick up where I left off when I get home.
Okay, so that leaves me with ordering the aux pump for around $100 if I assemble into the bracket system myself. I can live with that. If the injectors are all still in good condition then I can order new seals and mess with that after the pump is confirmed. I also am considering a new fuel filter basket thingy. In my rush to put stuff up last night it didn't want to seat right. I may have tweaked the flange where it seals a bit but will double check before ordering.
Finally got a moment last night to wrap up the injector re-install. They are all back in and since the new pump is supposed to be delivered today, I removed the aux pump housing to clean it up a bit and make a quick swap this evening possible. Messy but done.
Then I sat around for a few minutes, realized I wanted to check on the fuel pressure sensor at the end of the fuel rail while there's no pressure in the system. A large wrench wouldn't fit in the space and I didn't feel like removing the whole rail. After digging through my deep sockets I found one that I thought should be adequate. It didn't reach full depth but had a good bite. Well it apparently also was biting the plastic connector and broke. Or at least it appears to be. Where it's glued to the metal is peeling away so highly doubt it's going to last long otherwise. So I ordered another one last night. Now I wait even longer because I couldn't just spend another 5 minutes doing things the proper way. Frick! I'll probably still try to crank it over this evening anyway. Cause I'm still impatient.
Great progress!
Were the injectors difficult to remove or did they just pulled out? Did you use some sort of slide hammer?
In reply to Slippery :
Super easy to remove with the tool I ordered on Amazon for $20 with one day delivery. The different fitting options are m8, m12, and m14 which is what I needed. Definitely worth every penny.
Thanks! Will order that and tackle that valve cover gasket.
In reply to Slippery :
I think you will be happy with the purchase. Each one of mine weren't going to come out easily otherwise and for the money it's hard to beat.
Hi have you removed the solenoid off the top of the high pressure fuel pump and checked for metal bits in pump as that will give you no fuel pressure
Got the new aux pump installed in the factory bracketry, then back in the car. I planned to re-tighten the pressure sensor in hopes to start cranking over the car but apparently the aux pump being back in the car left zero room for my socket to fit. Since the new sensor will be here Monday I decided to just pull the rail so it will take less time to install when it arrives.
Here you can kinda see where the sensor is separating from the connector. I couldn't really capture how deep it opens up but you get the idea.
While twiddling thumbs I'm starting the process of cleaning and conditioning the leather seats with a combo kit from Chemical guys. They are cleaning up as good as expected. Still need to scrub all plastic surfaces as well. It's so gross or at least seems like it since everything is light tan.
In reply to Arosa14tdi :
Yup. No metal inside and the filter is clear of particulates. I actually pulled the piston of the HPFP and found what looks to be an excellent condition piston and cam lobe with zero signs of wear.
Hopefully it's just air locked then can be a pain to bleed but good luck
New sensor installed.
Primed the E36 M3 out of the system.
Bled the lines at the injectors.
Hooked up the Jeep to some jumper cables.
I had the wife steady revving to 2500 while I cranked on the beast for a while.
Nothing.
Dammit.
I guess I shouldn't say nothing, the fuel pressure fault code went away. What's weird is the measured pressure while cranking is still only 8 bar. I set up the injector bleed off kit, which isn't really helpful for the connectors on the Audi at all but I tried. While cranking there's no bleed off from the injectors but a little at the bleed line that feeds back into the rail. The kit is supposed to have plugs that block them off but it's designed to plug female holes and these are male. I may revisit this but for now I don't think it's going to help me in my current diagnosis.
I previously confirmed the intake side of the turbo was clear but not the exhaust. I know if the DPF is cracked, clogged, destroyed, etc. that there can be a no start so I started the process of disconnecting it. Someone has been in here before. There are supposed to be 3 nuts holding on the heat shield but only 2 are present. One of the studs for the third is no longer available. The v-band was fastened backwards where the allen was facing down and difficult to loosen. Then when I removed the o2 sensor I noticed it was looking pretty banged up. I imagine the PO did some DIY work but used a hammer or something to remove the thing, possibly for a DPF fault. So I may be on to something.
Anyway at this point I was drenched in sweat for the 50th time and getting bit by mosquitos. To get the DPF loose I need to get under the car and since it's parked in gravel I put my tools away. Time to push this thing into the garage. I don't know if it's the transmission on these that don't allow them to roll well in neutral but good god it's some work. Me and the wife managed to get it turned around and parked in the garage. I put the battery charger back on and called it a night.
So sometime this week I want to get the car in the air, disconnect the DPF and see if I can see any damage or manage to get the car to start with no obstruction. If the DPF is toast I may just delete it and the EGR with a Rawtek kit. A Malone stage 2 tune would be a hoot. If the car doesn't start, then I'm back to maybe one of the injectors being the problem?
In reply to captainawesome :
When they run, they are great. Hopefully you zero in on something without too much additional outlay. Take a look at Darkside Developments out of the UK for delete components, depending on the exchange rate they may be cheaper than Rawtek. That is the route I was going to go on my 2014 Golf before I started fighting intercooler icing issues and dumped it.
In reply to 10001110101 :
It looks like there are a few options out there but Darkside is on the list for sure. I really would like a muffler and for sure a cat in the system. It's hard to tell how loud these get when deleted but I don't want loud or stinky.
As I'm in the UK I've used Darkside and there parts and service is top quality
In reply to captainawesome :
Get a good battery hooked up in there, jump starting is not a substitute in my opinion. Sorry the car didn't start yet but you're moving right along!
In reply to dculberson :
It's a great battery. Started off at 12.9 before adding in the jump for more possible juice as it can drain fast with just cranking. I still was above 12 when I called it quits. I keep a tender on it so it's always ready to crank with testing.
In reply to Arosa14tdi :
I didn't see a catted option but shipping wasn't as bad as expected. I may go with the FLOWDIREKT option but still not decided on anything yet.
In reply to captainawesome :
You have to cut just below the DPF filter for removal. It won't come out whole.
I went with EOC performance. I haven't installed it yet. The quality looks on par with rawtek.
In reply to clutchsmoke :
I've removed it whole before on my previous a3, but it requires removing the passenger axle and I think loosening the subframe? Maybe just the axle but it's super tight.
Looks like EOC is just selling the FLOWDIREKT kit so I'm keen to hear what you think of it.
Thought I found the smoking gun today.
Even though I still wanted to mess with pulling the DPF just enough to check for blockage, the idea I'm still reading only 8 bar while cranking just doesn't sit well with me. If I'm not getting 300 bar it's not going to activate the injectors. Period.
So I set up the injector bleed off test, blocked off the return line, and got zero leakage. I still don't know if they leak out the top or in the cylinder when they fail. I assume the top back into the return otherwise I should have gotten some sort of hydraulic lock? Also as noted above they shouldn't fire unless they are getting 300 bar while cranking.
Then I decided to test the fuel pressure regulator valve again. For whatever reason when I primed the pumps it was leaking out with the key on!!!! So I went to dinner on a high. I finally figured it out right? Nope. When I came back to test it again it only leaks with the key on until I start to crank it over. Then it seals right up. So I think that rules out the valve being defective? FRICK.
I also wanted to try to see if one of the injectors is bleeding off into the cylinder by pulling the glow plugs. Apparently the cylinder with fuel will spray out of the glow plug hole which would help me narrow down the injector. Got one out easy and the second cylinder started to struggle. The third one didn't really want to budge without more pressure than I was willing to give so I aborted that idea.
I'm pretty sure it's an injector? Other than the possibility that the high pressure fuel pump isn't working properly even though it appears to be in great shape. I'd need to buy a $300 tool to test that theory. Right now I'm just trying to not rush into buying injectors for no reason. Especially if the pump is bad. There has to be something I'm missing in my tests or how to test items to confirm before dumping money at it.
If its a bad injector, wouldn't it run in 3 cylinders? Or is the bad one stuck open and you are bleeding off pressure that way?
Not sure those are the right questions as I am not 100% familiar on how diesels work.
