Testing for a blown turbo

Tourist · Post by **Tourist** » Wed Feb 18, 2009 11:21 am

Sorry to be such a newbie not knowing which pipe to check, is this the one:

If it's the wrong pipe then this was for nothing but I did take the jubilee clip off and test for air coming out. There is some, but not much. I could easily hold my hand infront of it. I also tried driving with the pipe removed and it drives the same, or atleast there's minimal difference that's hardly noticeable.

I can still hear the turbo, I love that sound but I wish the power was going to the engine, so the car could sound cool and go fast!

In advance ... if this is the wrong pipe then please correct me

RichardW · Post by **RichardW** » Wed Feb 18, 2009 12:09 pm

You got the rest of that photo? That thin pipe under your finger - what's it connected to???

Tourist · Post by **Tourist** » Wed Feb 18, 2009 12:24 pm

Sorry but that is the whole photo. I just went out to have a look for you. In extremely crude terms it connects to "that silver bit" where the throttle is, the other end disappears down the back down one side of the intercooler.

I wish I could be more specific but I don't know what I'm looking at.

RichardW · Post by **RichardW** » Wed Feb 18, 2009 12:42 pm

tourist wrote:"that silver bit"

Which is the injection pump

That is the boost sensing pipe. I'm pretty sure it should be connected to the front of the intercooler (we are going back 8 years since I looked under the bonnet of a BX TD!). Is the other end actually connected to anything?? If not, then you have probably found the fault....

Tourist · Post by **Tourist** » Wed Feb 18, 2009 12:53 pm

RichardW wrote:Which is the injection pump

Ofcourse, I knew that!

It definitely looks like it's supposed to be there, as to where it goes I have no idea. Tried pulling it, and it doesn't move so my guess is it's connected to something.

I can't get any more pictures up at the moment, I didn't bring my cable to connect the phone to the PC but I can try and get some more later if they're of any help to anyone in diagnosing this problem?

Thanks Richard for your reply.

jonathan_dyane · Post by **jonathan_dyane** » Wed Feb 18, 2009 3:08 pm

RichardW wrote:
tourist wrote:"that silver bit"
Which is the injection pump

That is the boost sensing pipe. I'm pretty sure it should be connected to the front of the intercooler (we are going back 8 years since I looked under the bonnet of a BX TD!). Is the other end actually connected to anything?? If not, then you have probably found the fault....

I *think* that is in fact the diesel return; the boost sensing pipe runs from the middle centre of the intercooler to the front of the injector pump.

RichardW · Post by **RichardW** » Wed Feb 18, 2009 4:11 pm

jonathan_dyane wrote:I *think* that is in fact the diesel return

Oops

probably is. Looks like a Lucas pump from what can be seen - I'm not that familiar with them, all but one of mine have been Bosch pumped. Need a bigger pic to confirm!

Tourist · Post by **Tourist** » Wed Feb 18, 2009 5:28 pm

I can confirm that I have the Lucas fuel pump. Must be a BX thing, because I thought turbos always had the Bosch. Maybe this is because it's the XUD7 and not the 9, I don't know?

Here are a couple more pictures of that smaller pipe. Here it is at the visible end ...

This is the other end that disappears down the side of the intercooler. My finger is on the pipe because of bad lighting:

Are these any help?

Was I checking the right pipe, the one that comes directly from the intercooler, or was this not the one David Rutherford meant in his test, which is the 5th post in this thread:

http://www.bxclub.co.uk/forum/viewtopic ... sc&start=0

DavidRutherford · Post by **DavidRutherford** » Wed Feb 18, 2009 6:28 pm

Right. With a warm/hot engine:

Grab hold of the big rubber flange around the intercooler and pull it off. Disconnect the 2" diameter pipe you've pointed to, and leave it resting on the stub of the intercooler. Now start the engine, allow it to idle a bit and then rev it HARD. (right round to the red-line) Massive volume of air should come out of that pipe. (as I said before.. do NOT check this with your hand. Hang something in front of the pipe and see if it's blown away.)

If it doesn't, check that the other end is attached to the turbo. The turbo is *just* visible down the back of the engine. Much easier to see from underneath, but I suspect you don't have access to that area.

If you can hear turbo whistle then the turbo is spinning and venting it's pressureised air to atmosphere somewhere.

The only other possibility is that the turbo is completely siezed, and what you can hear is the exhaust gasses fighting their way past the expander wheel. Not impossible, but it'll be the first one I've ever heard of.

Tourist wrote:Must be a BX thing, because I thought turbos always had the Bosch

Where did you pick up that entirely wrong piece of information? Any XUD7, 9, 7T or 9T (IE almost any XUD engine at all) can have either Bosch or Lucas equipment.

Post by **mat_fenwick** » Wed Feb 18, 2009 7:39 pm

DavidRutherford wrote:The only other possibility is that the turbo is completely siezed

Or that some joker has put an intercooler on top of a non turbo engine...I have actually known of this happening!

EDIT - Have just re-read the post properly and at least you can hear the turbo, and can feel some air coming out. So you do have a turbo!

Tourist · Post by **Tourist** » Wed Feb 18, 2009 7:46 pm

mat_fenwick wrote:EDIT - Have just re-read the post properly and at least you can hear the turbo, and can feel some air coming out. So you do have a turbo!

Yep it's definitely there.

David as regards to fuel pumps I was talking about XUD9 engine specifically, as a general rule the n/a engines were fitted with the Lucas pump, and the turbos with the Bosch which is the better one, and also the pump you can run veg oil with. My fault ... didn't word it very well.

Just to be clear, you want me to remove the bigger pipe in the first picture? How much air should I expect to come out? I know there's enough to blow a piece of paper away, that much is clear from todays test but should there be more? I'd describe it currently as being about the same as a hair-dryer.

Kitch · Post by **Kitch** » Wed Feb 18, 2009 7:53 pm

Tourist wrote:
mat_fenwick wrote:EDIT - Have just re-read the post properly and at least you can hear the turbo, and can feel some air coming out. So you do have a turbo!
Yep it's definitely there.

David as regards to fuel pumps I was talking about XUD9 engine specifically, as a general rule the n/a engines were fitted with the Lucas pump, and the turbos with the Bosch which is the better one, and also the pump you can run veg oil with.

You do seem to have a habit of preeching to the preechers in their own back yard don't ya?

It's more to do with who PSA got a better deal off at the time of building. My Xsara is an XUD9TE, and look.....

jonathan_dyane · Post by **jonathan_dyane** » Wed Feb 18, 2009 7:56 pm

Tourist wrote: David as regards to fuel pumps I was talking about XUD9 engine specifically, as a general rule the n/a engines were fitted with the Lucas pump, and the turbos with the Bosch which is the better one, and also the pump you can run veg oil with. My fault ... didn't word it very well.

As David pointed out, it's not a question of wording, more a question of being wrong; there is no correlation between turbo/NA and Bosch/Lucas in the BX.

MULLEY · Post by **MULLEY** » Wed Feb 18, 2009 8:01 pm

I must admit to believing rightly or wrongly, that most n/a ones came with the bosch pump. I am aware of others that have the other pumps as well, but for the most part they were mainly bosch.

Where as the turbo's seem to have anything fitted, even cars made in the same month have different pumps fitted, supply & demand i guess...

Tourist · Post by **Tourist** » Wed Feb 18, 2009 8:06 pm

With the turbos I think it's just what they had in stock at the factory.

jonathan_dyane wrote:there is no correlation between turbo/NA and Bosch/Lucas in the BX.

Of all the cars I've seen, when it comes to the XUD9 I've only ever seen Bosch in the turbos and Lucas in the others. Not that this matters ...