Help needed - engine idle @ 2500rpm

[Jamesl172]

Started to polish my engine bay and today i tried to remove the engine plenum, after an hour of getting it half off and not being able to get it off completely i decided to leave it for another day and put it back on. Turned my car on and it is reving to 2500rpm and a strong smell of petrol. Need some advice please

 

[mattjk]

I reckon you have either not connected the AV pipe or the brake servo pipe. Check plenum again and make sure everything is plugged in.

 

[Jamesl172]

just had another look, some black tube pipe on the back was off, had to tape it back on as it kept slipping off - is that the av or brake servo pipe? cheers.

 

[mattjk]

Some black tube pipe - Thats very descriptive.

Its likely to be the brake servo pipe but It could also be the pipe going to the carbon canister

The AV is the small pipe at the front just next to the TB which leads down to the bottom nearside wheelarch

 

[bmh.01]

For it to go to 2500rpm i'll put money on it being the brake servo vacuum pipe, the others aren't big enough. The a/v only takes it to about 1500rpm tops.

http://gallery.getflat.co.uk/v/My_C..._Plugs/DSC00137.JPG.html?g2_imageViewsIndex=2

The one at the back right of the block with the bit of hose crimped on the end?

 

[mattjk]

Yeah your right. But thought I'd mention it anyway

How important is the TPS input? Would the engine be running lean as the air enters after the TB?

 

[Jamesl172]

Looks like it was the brake servo pipe - aka the black tube pipe. Cheers

 

[bmh.01]

Yeah your right. But thought I'd mention it anyway

How important is the TPS input? Would the engine be running lean as the air enters after the TB?

What as in the throttle input from the pedal?

An air leak shouldn't make it run lean as the engine uses MAP instead of MAF so it should sense the extra air in the same way as is does when you open the throttle.

 

[mattjk]

Pretty much. I thought that the TB sends some form of I'm 50% open and the ECU takes this into account and this subsequently has an effect on fuelling? Eductaed guess really. I cant have thought it would have a major effect just the car would see extra air and get confused possibly screwing the mix. (ovi only applies to FBW)

Im probably way off LOL

 

[bmh.01]

Pretty much. I thought that the TB sends some form of I'm 50% open and the ECU takes this into account and this subsequently has an effect on fuelling? Eductaed guess really. I cant have thought it would have a major effect just the car would see extra air and get confused possibly screwing the mix. (ovi only applies to FBW)

Im probably way off LOL

Not really, fuelling is mostly control by the air flow/pressure for example as air is denser when cold so the ecu needs to take account of this and inject more fuel, this is obviously completely independant of throttle position. The throttle position will be used to calculate engine load though which will may have an effect on fuelling though, but in this case I doubt it makes any difference other than it idling high. It won't be running lean enough to do any damage anyway.

 

[mattjk]

Thanks for the detailed explantion as always Ben

 

[Andyman]

just had another look, some black tube pipe on the back was off, had to tape it back on as it kept slipping off - is that the av or brake servo pipe? cheers.

Id be better a proper jubilee clip on if it was me. That thing comes off and use lose your brake vacum which = no brakes !

 

[D1CKY]

Agree with Andy mate get a jubilee clip on it

 

[Andyman]

BTW ignore my dodgy grammer. Was a very hot day yesterday