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AWM won't start. Timing fine. Won't hold pressure/vacuum.

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  #11  
Old 05-29-2018, 10:16 AM
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Originally Posted by mobildetroit
Take the oil filler cap off and crank the engine over. If it doesn't sound like it's flying over a cylinder then I don't suspect you have a mechanical issue with the valves or cylinder. If your compression check is nominal then I suspect you have an electrical issue of some kind, like power supply to ignition. Have you taken your plugs out yet?
I have taken the plugs out.
 
  #12  
Old 06-01-2018, 06:58 PM
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Have you checked fuel pressure? If the pressure is to high it could cause the engine not to start. I found out this is my issue with my audi not starting...fuel pressure to high and it fouls the plugs on start...
 
  #13  
Old 06-02-2018, 07:48 AM
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I think it needs a head job. I was in Chicago for the past week and my 14 year old son pulled the valve cover off and noticed that three of the cylinders had issues on the exhaust side. He told me the things that the cam lobes push down on were all down without having the lobes pushing on them. I forgot the name of them, but whatever it is that covers the valve springs. So either I busted a bunch of valve springs, or I bent a bunch of valves without losing timing. It's very odd.
 
  #14  
Old 06-02-2018, 07:49 AM
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I really need to do a compression test, but I don't have my compression set anymore.
 
  #15  
Old 06-02-2018, 04:30 PM
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Do you have the engine rev limiter defeated or set to a higher RPM? It's high RPM that usually breaks springs.....other then just fatigue. It's possible you could have a bent valve as a result. Either way the head is coming off to fix it, you will know your piston condition then. If the engine was running fine before then, no reason to suspect issue with rings...I wouldn't crank the engine anymore then you need to at this point.
 
  #16  
Old 06-03-2018, 12:09 PM
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My 14 year old son ended up diagnosing it better than I could. lol.....and he only recently got into cars.

While I was out of town on business this past week, he took it upon himself to pull the valve cover and he noticed that (on 3 of the cylinders) the spring covers/whatever you call the component that the cam lobes actually make contact with, were down on the exhaust side (as if they were being push down by the cam), but the cam lobes weren't touching them at all. He even bumped the engine with the key, just to make sure what he was seeing was not an isolated incident.

Now I'm wondering: Could this be an oil pickup tube issue (because Ross Tech says that one of the codes the car threw is often a P/U tube problem in the 1.8t specifically).Do you think it's worth dropping the pan? Is that valve train hidrolic?
 
  #17  
Old 06-03-2018, 12:44 PM
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I'm pretty sure a loss of oil pressure at the hydraulic lifters (which the 1.8t has) wouldn't prevent the car from starting.

When you disassemble the valve train, you must wait at least 24 hours for the lifters to bleed off oil pressure before you reinstall the cam shafts. Otherwise you risk bending valves during the reassembly. So, this means if you let your car sit for 24 hours, it should be able to start without the lifters having full oil pressure.

Given the fact that your car just quit on you while you were running suggests that you do not have an oiling problem at your lifters. If you did have an oiling problem at your lifters, I would expect it to affect more then a few lifters. Also, if you had an oiling problem at your lifters I would expect you to have a more severe oiling issue at your cam bearing caps, and you could even possibly have some obvious bearing wear.

If you are a person who runs synthetic oil in your engine, I would not expect any sludge issues with your pick up tube at all. Also, the pick up tube in these engines are bolted on they don't fall off.

I'm curious though, what is the engine code you were getting and what is Ross-Tech saying?
 

Last edited by mobildetroit; 06-03-2018 at 01:14 PM.
  #18  
Old 06-04-2018, 01:48 PM
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Originally Posted by mobildetroit
I'm pretty sure a loss of oil pressure at the hydraulic lifters (which the 1.8t has) wouldn't prevent the car from starting.

When you disassemble the valve train, you must wait at least 24 hours for the lifters to bleed off oil pressure before you reinstall the cam shafts. Otherwise you risk bending valves during the reassembly. So, this means if you let your car sit for 24 hours, it should be able to start without the lifters having full oil pressure.

Given the fact that your car just quit on you while you were running suggests that you do not have an oiling problem at your lifters. If you did have an oiling problem at your lifters, I would expect it to affect more then a few lifters. Also, if you had an oiling problem at your lifters I would expect you to have a more severe oiling issue at your cam bearing caps, and you could even possibly have some obvious bearing wear.

If you are a person who runs synthetic oil in your engine, I would not expect any sludge issues with your pick up tube at all. Also, the pick up tube in these engines are bolted on they don't fall off.

I'm curious though, what is the engine code you were getting and what is Ross-Tech saying?
I do run synthetic and I've never really had/noticed any sludge. On top of that, my valve train is still covered in oil, so I'm pretty sure oil is making it's way through the channels.

I can't believe I deleted the printout of the codes, but I got a crank/cam/whatever the **** they call it sensor code, saying that it didn't match up with the cam sensor (I've replaced both). I also got a "rev too high - warranty void" code, but my redline is set at 7,200 so I'm not really concerned with that. It's probably from putting a teenager in his place prior to the failure. The one that worries me the most is the knock sensor threw a code saying that the signal was too high (I replaced that too).

One of the more important codes (per Ross Tech) had an asterisk saying that "in the 1.8t, this is commonly a problem with the filter on the oil pickup tube."

Should I drop the pan you think?
 
  #19  
Old 06-04-2018, 01:58 PM
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I'm pretty sure the rev limit on the AWM should be around 6900. If you went into the red you could potentially break OEM springs. I don't suspect you have an oiling issue due to plugged pick up screen on pick up tube. If you did and you broke springs as a result, your engine would have been trashed before the springs broke and it would be vary obvious seize up.

I'm not convinced you have/had any bad sensors or oiling issues.

http://www.wilhelmautomotivegoodyear...t-your-engine-

 

Last edited by mobildetroit; 06-04-2018 at 02:01 PM.
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