Intake manifold blockage ?

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Benscab123
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Intake manifold blockage ?

Post by Benscab123 »

Can someone tell me please - if my intake manifold had bad carbon build up, could this cause EGR insufficient flow and turbo underboost ?
Not sure if it is blocked but just wondered if that’s possible before I get it looked at.
Thanks.
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white exec
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Re: Intake manifold blockage ?

Post by white exec »

Not sure about all engines, but there are some natty endoscopes (miniature camera on end of flexible USB connection, so ideal with a laptop) on Amazon, and not expensive. Might help assess curvy pipework/manifolds, as well as inside sills, etc.
dave_xsara
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Re: Intake manifold blockage ?

Post by dave_xsara »

I just bought one on ebay yesterday for ~£7 with 2m cable for checking the inlets on mine when I clean them next week. They can be viewed on a mobile phone too.
Endoscope or borescope is what they are listed under.

It is more likely that the cooler pipe from the EGR to the inlet manifold is what is clogged. (viewtopic.php?t=64524)
If your inlet is coked up then the pipe from the EGR up to the inlet will also require cleaning.

You should be able to see inside the inlet by just taking off the pipework from the airbox.
Gibbo2286
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Re: Intake manifold blockage ?

Post by Gibbo2286 »

I've got one of those cheap endoscopes but to be frank it ain't a lot of good.
Benscab123
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Re: Intake manifold blockage ?

Post by Benscab123 »

Thanks for your replies, when my EGR was replaced I did ask the mechanic to take a look at the pipework to see if it was clogged and he said “ they’re a sealed unit, you can’t get into them to clean”. I thought that was a fob off at the time, now I KNOW it was ! Probably couldn’t be bothered.
As I’m not too mechanically minded, where is the air box please ?
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myglaren
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Re: Intake manifold blockage ?

Post by myglaren »

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white exec
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Re: Intake manifold blockage ?

Post by white exec »

Isn't that an exhaust manifold? #-o
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Paul-R
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Re: Intake manifold blockage ?

Post by Paul-R »

That's what I thought except it looks like it's made from cast ally. Now, unless it's a fairly recent thing, I thought exhaust manifolds were made from cast iron or tubular steel.
dave_xsara
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Re: Intake manifold blockage ?

Post by dave_xsara »

Nope thats de-coking an inlet. I've viewed that video too :D
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Paul-R
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Re: Intake manifold blockage ?

Post by Paul-R »

I'd like to see that repeated with a plastic inlet manifold!
Gibbo2286
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Re: Intake manifold blockage ?

Post by Gibbo2286 »

I wonder how far a car could travel on the fuel burned in that show.
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Hell Razor5543
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Re: Intake manifold blockage ?

Post by Hell Razor5543 »

Quick, shove the bangers and burgers on a grill and barbeque them!
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white exec
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Re: Intake manifold blockage ?

Post by white exec »

You're right - inlet. They used to run clean, even polished, once-upon-time.
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myglaren
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Re: Intake manifold blockage ?

Post by myglaren »

white exec wrote:
07 Feb 2020, 17:58
Isn't that an exhaust manifold? #-o
It is now :)

Looks like it because of the flames.