Cam follower replaced, hesitant start ever since

[a4937]

If it's not warmed up it takes several seconds to start. I think this is my 4th time doing it and haven't had any issues prior. I already went through the process again but no change.

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[Jayz691]

Sounds like something went wrong. Check what your fuel pressures are when trying to start it.
Do you have a late model(07-08) with rubber inlet hose? If so, do you completely remove hpfp, when doing CF service?

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[a4937]

Sounds like something went wrong. Check what your fuel pressures are when trying to start it.
Do you have a late model(07-08) with rubber inlet hose? If so, do you completely remove hpfp, when doing CF service?

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I do have an 07, and I don't remove it all the way. I think I got it just now. Somehow during the process I loosened the connector on the pump instead of the fitting on the hard line. Got all that back where it needs to be so hopefully I'm good to go!

Thanks for responding!

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[Theiceman]

and you didn't have a fuel leak ?

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[a4937]

and you didn't have a fuel leak ?

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I did. That's what helped me figure it out. It wasn't horrible, and my gas gauge has always went down faster after a half tank but I got gas Wednesday night and seeing how much I used from a full tank just commuting to and from work yesterday made it fairly obvious.

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[Theiceman]

Jesus you are are lucky lol...

[67Twisty]

Jesus you are are lucky lol...

No doubt. Could have been a fireball

[a4937]

No doubt. Could have been a fireball

Would you mind humoring me and explaining to me like I'm five how this could happen? lol

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[67Twisty]

Pretty basic, but if fuel is leaking from a high pressure fuel pump (of even via the low pressure line pre-pump), gas can ignite in the presence of ignition source or heat. While the spark plugs and coil packs are on the opposite side of the head, the fuel could easily migrate over to the hot side of the exhaust manifold and ignite.

[a4937]

Pretty basic, but if fuel is leaking from a high pressure fuel pump (of even via the low pressure line pre-pump), gas can ignite in the presence of ignition source or heat. While the spark plugs and coil packs are on the opposite side of the head, the fuel could easily migrate over to the hot side of the exhaust manifold and ignite.

Thanks, couldn't figure out how it would ignite but that makes sense.

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[a4audi4fun]

Surprised you didn't smell any gas at all with losing as much fuel as you said. I only had a slight weeping from my HPFP and could smell gas as soon as I parked the car in the garage.

[PhireSideZA]

Same situation when I discovered that mine was weeping. Tightening my banjo fitting didn’t do squat for my fuel consumption though.

Perhaps some brands of fuels are more aromatic than others? Some brands here by us have a noticeably stronger petroleum smell than the competition, although that was more of a thing back when we had leaded fuels available

[80sGuy]

So are you guys saying the CAM FOLLOWER job is an extremely dangerous one? Because I'm about to tackle mine soon and have no idea, of course I'll go through a plethora of video instructions but this is making me nervous!

[a4audi4fun]

@80sGuy - no, it's a straightforward job to replace the follower but obviously because you are removing the HPFP pump as part of the process you have to be very careful handling the fuel lines and confirming nothing is leaking/weeping after the replacement of the cam follower has been completed. The concerns raised during this discussion were because the OP was driving multiple times with what sounded like a lot of fuel leaking - that's when things can get dangerous as heat and gas outside the engine is not really a good situation to be in for the reasons as described by 67Twisty.

Do things slowly and double check all the fuel connections (even if you haven't loosened anything) before starting or driving. Monitor for fuel leaks a few days after as well just to be sure.

[Theiceman]

do NOT over torque the three bolts holding the pump to the timing cover after years of fatigue, those threads strip VERY easily . even hand night holding the shirt end of the Allen key is fine.

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[67Twisty]

Those three bolts are torque to yield/stretch bolts and technically should be replaced whenever the pump is removed. Most owners/mechanics reuse them and never have an issue, but that’s why the threads can slip as iceman pointed out. Also good practice to replace the fuel pump o ring whenever it’s out. Cheap insurance to prevent oil leaks.

[Theiceman]

Those three bolts are torque to yield/stretch bolts and technically should be replaced whenever the pump is removed. Most owners/mechanics reuse them and never have an issue, but that’s why the threads can slip as iceman pointed out. Also good practice to replace the fuel pump o ring whenever it’s out. Cheap insurance to prevent oil leaks.

I would not think those bolts are tty. the threads would never withstand it.

I thought they were only 11ft lbs or something.

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[Jayz691]

Those three bolts are torque to yield/stretch bolts and technically should be replaced whenever the pump is removed. Most owners/mechanics reuse them and never have an issue, but that’s why the threads can slip as iceman pointed out. Also good practice to replace the fuel pump o ring whenever it’s out. Cheap insurance to prevent oil leaks.

Theyre not TTY. Tq is only like 8ftlb. I just use a mini ratcheting bit driver, so I can't over tighten them. But good to replace at least every few uses.

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[Jayz691]

So are you guys saying the CAM FOLLOWER job is an extremely dangerous one? Because I'm about to tackle mine soon and have no idea, of course I'll go through a plethora of video instructions but this is making me nervous!

Its very easy, esp if its an 07-08 with rubber inlet hose. Ya don't have to remove the hose. 17mm crows foot wrench and extension work best for hard line. And just snug the 3 bolts. I put some assembly lube on CF/Hpfp whrn installing.

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[67Twisty]

Theyre not TTY. Tq is only like 8ftlb. I just use a mini ratcheting bit driver, so I can't over tighten them. But good to replace at least every few uses.

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My bad. I had assumed they were stretch bolts based on the online order note I saw about replacing whenever the pump is removed. Makes sense they’re not TTY since the timing cover is aluminum and torque specs are low.

[Theiceman]

My bad. I had assumed they were stretch bolts based on the online order note I saw about replacing whenever the pump is removed. Makes sense they’re not TTY since the timing cover is aluminum and torque specs are low.

yup thought so

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