3k idle on volvo clio, cuts out when accelerator pressed

[Chesh]

This has been copied across from another forum as i really need to get this sorted asap if the car is coming to fcs so sorry if it doesnt make sense! Background information, the car is a mk1 with a b18ft from a volvo 480 and when i first started it i did not have this problem, it has only come after fitting the downpipe. anyway, heres the original post:

Original post:
Fitted my downpipe today (thanks reevio ) and went to start it and as soon as i start the car it will slowly rev up to 3k and sit there. If i press the accellerator at all it will cut out straight away.

It wasnt doing this before I fitted the downpipe and that is the only thing i have changed since i started it last! I have had a look on the (very quiet) volvo forums and have found that it may be a bolt that i have missed thats function is to fill a hole which becomes an air leak but this was missing when i started it without the downpipe still and it didnt have the problem. Could it be the extra back pressure from the downpipe causing the engine to suck more air from this hole??? Just throwing ideas out there lol.

I am going to try putting some more fuel in it as it is VERY low and putting a bolt in the hole tomorrow but in the mean time does anyone else have any ideas? We have had some rain over the last few days, could this be anything to do with it? Water getting in the sensors (wouldnt be the ecus, they havent been outside at all)

Here is a video, note the rising revs until you see the accelerator cable move and then it cuts out immediately

edit: Does the fact is cuts out when the accelerator is pressed a sign of an air leak cos thats what my thoughts were regarding the rising revs

edit: Yeah it does have a tps and it's plugged in. Seriously literally nothing has changed since I started it for the first time and it ran fine then! Could it have got wet? It's right in te middle of the engine bay so doubt it?

Just put the bolt in I was talking about and connected te exhaust and lambda and it's still doing it. Doesn't just idle up to 3k either, gets to 3k, hovers, revs dip then it cuts out.

edit: Would it have anything at all to do with the way the car regulates turbopressure. ATM the turbo is not connected to the throttle body because I don't have enough piping and really don't like buying things for it without knowing for sure whether it's going to run ok or not.

The three pipes connected to the turbo go to a little box that has a plug in it. Because there is nothing for the turbo to push against would it make it go funny and keep revving? Until it thinks f**k it and cuts out lol.

Pleeease help csers!

 

[Triki]

By the sounds of it, you need to try connecting everything up 1st. And then see how it runs.

The vac pipe's need to be connected.

 

[Chesh]

But it was working fine before I put the downpipe on???

 

[Chesh]

So no one else has any ideas???

 

[Beef-Mc]

Taken the downpipe off to see if its still doing it?

 

[Chesh]

Well im reluctant to do that because i see zero reason why it should cause the problem?

Will have to if there is no other ideas?

 

[Martin_172]

cant see it being down pipe even with less back pressure as it wont make a massive difference, sounds like you have a leak, vacume hoses, inlet/TB gaskets etc checked all that?

 

[Chesh]

It was running fine before i took it out the volvo and, as i have said, before i fitted the downpipe it was fine

But i will check eeeverywhere for leaks

However, i can see how the leaks would cause the rising revs but not the cutting out

 

[Triki]

It will cut out from running to lean.

Your pissing in the wind, trying to solve this without fitting all the relevent vac pipes etc.

 

[Chesh]

Ok I have now connected up eeverything! Piped the turbo straight to the throttle body and still does exactly the same thing. Revs up and then dies. Have tried it without the maf and tps connected, still does the same. Have checked all vac pipes, made sure all sensors are plugged in and checked all pipes that would make a difference to and from the turbo.

Could the turbo be jammed? :? Spun fine before.

 

[Chesh]

Just taken the downpipe off just to make sure and no change

 

[Josh2391]

So to get this straight (forgive me if ive missed something), have you fired it up and had it working properly WHILST its been in the Clio? Cos if you havent it sounds like theres something missing? Dont know if the 480 had an ECU, but make sure that is connected properly, what about fuel intake, is it getting enough fuel from the pump?

Might have some more suggestions for you later, will have a word with the old man. Knows more than I ever will about cars

 

[Chesh]

Yes, the first time it fired up it ran fine and revved fine as well, didn't cut out either. As soon as I fitted the downpipe which happened to be after it rained as well :-S the ecus weren't left connected so I know them themselves are ok but I don't know about the sensors in the bay?

 

[Josh2391]

Yeah might be your sensors mate, get them checked or replaced and see what that does.

 

[Chesh]

Tried properyconnecting up the turbo pipes to the tb and even blocking off the all the vacuum pipes and no difference.

 

[Josh2391]

Are you sure you havent missed anything?

 

[Chesh]

Pretty confident mate.

 

[Josh2391]

Ill have a word with the old man tonight, he might know something that will help

 

[MGM]

check the afm as they're known for being a bit fragile (the element inside them breaks)

also check that the vac pipe to the turbo ecu (the one that came out from behind the centre of the dash on the ovlov)

also if you can lay hands on a spare pair of ECU's it may be worth trying to swap them over

 

[Chesh]

Where does the vac pipe to the turbo ecu come from????

 

[MGM]

iirc it branches off a pipe from the inlet manifold

 

[Chesh]

Ok piped in the map sensor and plugged in another sensor that was where the breather enters the pipe to the turbo and still hasnt made any difference.

Seriously have zero ideas

 

[Chesh]

Most recent video of it, revs are hardly rising at all now but you can still hear them raise slightly.

Can hear quite well it cutting out, not sure if it possible to diagnose what is making it cut out from this?

 

[Chesh]

Couldn't be anything to do with immobiliser? Ecu light stays on when engine is started but could be to do with the amount of sensors on the Clio loom left unplugged lol

 

[Chesh]

Ok fuel pump is cutting out. Took the cover off the fuel pump and started the car, the pump whines for about 2/3 seconds and cuts out. I wanted to see if it was possible that the car would run without the pump running so unplugged it after it had stopped whinig and the car carried on running as usual and cut out as usual!

The car is very low on fuel, could this be the problem???

 

[Chesh]

Hard wired the fuel pump in and car works, no cutting out!

So yeah, cheers guys? :S

 

[Josh2391]

Thats really odd...
At least its fixed