Potentially huge problem

[seth_3515]

I started the car up the other day. It is a completely built 1.8t bottom end with with only exhaust valves in the head. I have an SEM intake manifold with the transition spacer. When u started it up it wasn't dim in the garage and I happen to notice light coming from the intake manifold flange. It was from the cylinder igniting! I hit the engine off right away and thought it could be the gasket. I tightened up but didn't help. The gasket seemed fine but i ordered 2 new ones anyways. As I thought about it more I thought it more, I didn't know if the valves would or should seal perfectly to the head. This would indicate the valve werent seated correctly or my timing could be a hair off. Im pulling the cover off to check the timing today. I just wanted some opinions and see if anyone has gone through/heard of this happening.

[Big_Tom]

something is wrong. ur not supposed to be able to see combustion like that. even if you did put a new gasket or 2, the problem will not be fixed.

[Charlie_M]

Time for a compression test, or better yet, a leakdown test.

[seth_3515]

Im thinking it's either the timing is off and the valve is still open or they at not seated properly everything I had done by a shop I had to redo it. I was hoping I wasn't going to have problems with it too.. O well, I'll be tearing into it and try to find the problem.

[jbutlertelecom]

Im thinking it's either the timing is off and the valve is still open or they at not seated properly everything I had done by a shop I had to redo it. I was hoping I wasn't going to have problems with it too.. O well, I'll be tearing into it and try to find the problem.

If the valve is open during combustion then you have bent valves. Combustion begins BTDC but mostly finishes @ TDC and after. If a valve was open during the event it is bent. I would think maybe that is a hint to the problem. Leakdown AND compression test will find the issues quick. Seems valvetrain related, possibly bent valves or sticking valves (not properly done valve stem to guide clearances) or both.
I would think either the engine wouldn't be running or it would have a hard time STAYING running with bent valves. Its possible there is only an issue with that ONE cylinder.

[seth_3515]

No I can see it on all 4 cylinders.

[schwartzmagic]

I know this is going to sound kind of weird but....

When my buddy first fabbed up my intake manifold he did it on my friends gti that was at his shop. For whatever reason the alternators were different from his to my car. When he fabbed it up on the gti he had 1 finger clearance. When I installed the intake mani on my car the bottom of the intake manifold was resting on the alternator which didn't let the intake manifold head flange seal up on the head. When we cranked the motor up and it was running there was combustion coming out from there... We put two powergaskets in the meantime until I could take my car in so he could fix it.

Don't know if that cool story will help you but check to make sure nothing is causing interference in letting your manifold flange from sitting and sealing properly.

Sent from my MB860 using Tapatalk 2

[seth_3515]

I know this is going to sound kind of weird but....

When my buddy first fabbed up my intake manifold he did it on my friends gti that was at his shop. For whatever reason the alternators were different from his to my car. When he fabbed it up on the gti he had 1 finger clearance. When I installed the intake mani on my car the bottom of the intake manifold was resting on the alternator which didn't let the intake manifold head flange seal up on the head. When we cranked the motor up and it was running there was combustion coming out from there... We put two powergaskets in the meantime until I could take my car in so he could fix it.

Don't know if that cool story will help you but check to make sure nothing is causing interference in letting your manifold flange from sitting and sealing properly.

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Thats why I got new gaskets. I plan on checking the timing first. If alls good then move to compression test. After that ill remove the transition spacer and attempt to seal the manifold without the spacer and move on from there.

[schwartzmagic]

I would check to make sure it is sealed properly first. Sounds to me like that is what your issue is. I mean if you installed this transition spacer and you're seeing combustion then the only reason why you're seeing it can only be because of a poor seal. After you double and triple check then check timing and then compression test.

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[seth_3515]

I would check to make sure it is sealed properly first. Sounds to me like that is what your issue is. I mean if you installed this transition spacer and you're seeing combustion then the only reason why you're seeing it can only be because of a poor seal. After you double and triple check then check timing and then compression test.

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This was my first thought. But I didn't know if the valves Should have sealed off the intake from seeing any combustion at all. That's why I came here. I knew I wasn't getting a good seal at the manifold for some reason but was concerned about the valves not sealing properly. This is what led me to think the timing could be off or god forbid bent valves.. I don't think it's bent valves though as it runs but we shall see tonight

[Big_Tom]

i don't think you have bent valves... it's more likely timing is off and you need a new intake mani gasket. FWIW, my car was nowhere close to starting when i had bent halves in the head. i have a felpro intake mani gasket from autozone and so far it's been very nice.

[seth_3515]

I'm thinking the same thing Tom. I replaced the half moon seal and double checked the timing but it could have moved on me. It had a vacuum leak i have been trying to find and i Already suspected the intake manifold. I'll be looking tonight when I get home after class and post up what I find. I'm thinking the timing is off just a bit and the gasket.

[formerly silveratljetta]

How does the car even run if you have that big of a vacuum leak on the intake manifold?

[schwartzmagic]

Richard my car started up and the motor idled just fine when the manifold wasnt sealed up... It just sounded like popcorn popping lol

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[formerly silveratljetta]

Richard my car started up and the motor idled just fine when the manifold wasnt sealed up... It just sounded like popcorn popping lol

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Like when my injectors weren't sealing properly

[seth_3515]

Well the timing was nearly perfect. The cam gear could be moved just a touch to be perfect which I'll do today. New gaskets will be in tomorrow from IE. I'm contemplating having the manifold flange machines flat but haven't decided for sure just yet.

[schwartzmagic]

Did you bother checking whether they were warped? Do that before you go and spend money on having a shop machine your aluminum intake manifold flange flat. I've never heard of one warping. I'm still putting my money on the flange not making a good seal whether from something not letting it sit flush, a bad gasket or as Richard said maybe the injectors not sitting properly.

[seth_3515]

Did you bother checking whether they were warped? Do that before you go and spend money on having a shop machine your aluminum intake manifold flange flat. I've never heard of one warping. I'm still putting my money on the flange not making a good seal whether from something not letting it sit flush, a bad gasket or as Richard said maybe the injectors not sitting properly.

I haven't yet. Just checked over things yesterday and removed it all. I'll be checking it today, but I doubt it is. I did check to see if anything like vac fittings were hitting the alternator and everything seemed to be clear. New gaskets will be here tomorrow so I'll probably just double check everything and make sure to tighten the bolts fr the middle out. I couldnt remember if I did this or not (similar sequence to the exhaust manifold)

[Slimjimmn]

Don't know if that cool story will help you but check to make sure nothing is causing interference in letting your manifold flange from sitting and sealing properly.

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lolzzz

just like the ebay exhaust manifolds that have too thick of a flange so you cant tighten them down.

[seth_3515]

New gaskets arrived and didnt help.. I pulled everything off today and retimed everything. Everything is lined up exactly. I have 16 rollers between the cams, cam gear and crank pulley are spot on as well. I also got rid of the transition spacer for now to reduce potential leak points. If this doesnt help, Ill probably send the head off to be diassembled and reassembled by a reputable shop like PAG or IE. Its either the timing was off or the valves are not seating properly to seal them. I have never rebuilt a head or hand-lapped valves but I have been learning quite a bit online about it. If I had an extra or bad head I would practice and might try it but im not using this head as the guinea pig ATM.

[Slimjimmn]

pretty sure I would boost leak check the intake system before pulling a head.

If the manifold is not seating to the head a boost leak check at the throttle body will show that in 2 seconds

[jbutlertelecom]

New gaskets arrived and didnt help.. I pulled everything off today and retimed everything. Everything is lined up exactly. I have 16 rollers between the cams, cam gear and crank pulley are spot on as well. I also got rid of the transition spacer for now to reduce potential leak points. If this doesnt help, Ill probably send the head off to be diassembled and reassembled by a reputable shop like PAG or IE. Its either the timing was off or the valves are not seating properly to seal them. I have never rebuilt a head or hand-lapped valves but I have been learning quite a bit online about it. If I had an extra or bad head I would practice and might try it but im not using this head as the guinea pig ATM.

LEAKDOWN test before you yank that head will tell you if the valves are seating properly or not.
DO IT!

[seth_3515]

pretty sure I would boost leak check the intake system before pulling a head.

If the manifold is not seating to the head a boost leak check at the throttle body will show that in 2 seconds

Even if the manifold is not seated, the valves should seal the cylinder off to prevent me from seeing light/fire from under the manifold. The timing is off or the valves are not seated correctly. I took the timing belt off and retimed everything individually to ensure they were all spot on. If it doesnt help tomorrow, Ill be going to pick up a new leak down tester to see if I can find a clue. Its not just one cylinder its all 4, this is leading me to believe it was timing related. Hence, I messed with it first rather than a leakdown test yet.

[Slimjimmn]

You should never be able to see combustion flames unless you have itb setups.
If you see flames the intake is not seated against the head or there are holes in the flange welds.

[seth_3515]

Pulled the transition spacer out and it sealed right up.. Unfortunately it had a really rough idle. Pressure tested the intake and found leaks at the injectors Ill be trying a dab of petroleum jelly on them tomorrow and see if they seal..

[schwartzmagic]

Told you your intake manifold flange wasn't sealed properly

Glad you found the issue. Don't petroleum jelly anything. If the injectors are leaking then you might want to check your o-rings and make sure they're in good shape.

[Slimjimmn]

Pulled the transition spacer out and it sealed right up.. Unfortunately it had a really rough idle. Pressure tested the intake and found leaks at the injectors Ill be trying a dab of petroleum jelly on them tomorrow and see if they seal..

and a set of orings at oreilly is like $11.00 for all 8
same orings as gm's and fords

[formerly silveratljetta]

Told you your intake manifold flange wasn't sealed properly

Glad you found the issue. Don't petroleum jelly anything. If the injectors are leaking then you might want to check your o-rings and make sure they're in good shape.

x2. Check the spacing on your injectors to make sure the o-rings are seated correctly in the injector cups. Viriato will tell you we had a problem on my car with the injectors not sealing correctly because they were too far down in the injector cups. They needed 2 washers on each fuel rail bolt to space the injectors properly.

[seth_3515]

x2. Check the spacing on your injectors to make sure the o-rings are seated correctly in the injector cups. Viriato will tell you we had a problem on my car with the injectors not sealing correctly because they were too far down in the injector cups. They needed 2 washers on each fuel rail bolt to space the injectors properly.

Nailed it. Put new orings on, didn't help. I used oem exhaust manifold washers, and they worked perfectly. Holds 14-15mmhg of vacuum at the moment. Idle AFR went from 1.5 to 1.2 lambda (have not touched the Ecu yet for fueling) Once it hits that smooth idle it'll hold it. Coming off the throttle it has to search just a bit but it's been getting better.