What is a Corrados CORRECT RPM idle speed

[belfastfumanchu 0]

To be specific, a 1.8 16v. Mine always idled just below 1000rpm but now if im driving and I have to stop at lights or something I thought she sounded like she was running a lot quicker and louder. I looked at the rpm and sure enough the rpms are more or less sitting spot on the 1000rpm or just above it now (not just below it which sounded more natural).

If I put my foot under the accelerator pedal and pull it up she comes back down to just below the 1000rpm mark.

 

Can anyone confirm for me that the correct idle speed should be just be below 1000rpm and give me a clue as to why she has suddenly started running richer? I know somethings not quite right.

[coolrado 0]

If I put my foot under the accelerator pedal and pull it up she comes back down to just below the 1000rpm mark.

 

if the revs drop when you pull the pedal back up with your foot you need to try adjusting and lubing the cable, or if the cable still doesnt return back all the way you may need a new throttle cable or rubber grommet that the throttle cable hooks into on the pedal end, the throttle should spring back until it stops when you take your foot off the pedal and there should be a little bit of slack in the cable.

[n3p 3]

Mine sits just under 1000 and its fine. There is adjuster located at the throttle valve housing, its basically a screw with a reverse thread.

[belfastfumanchu 0]

I put a new throttle cable on last summer and it's been ok until recently. I'll have a look at the adjuster and take it from there. Thanks lads.

[Yandards 0]

Correct idle speed with all electrics off (rad fan, heater motor, lights etc) when warmed up to 80 of water temp should be 1000 rpm +/- 50 rpm.

[boost monkey 0]

If I put my foot under the accelerator pedal and pull it up she comes back down to just below the 1000rpm mark.

 

if the revs drop when you pull the pedal back up with your foot you need to try adjusting and lubing the cable, or if the cable still doesnt return back all the way you may need a new throttle cable or rubber grommet that the throttle cable hooks into on the pedal end, the throttle should spring back until it stops when you take your foot off the pedal and there should be a little bit of slack in the cable.

 

Yeah possibly... coulde be gunk in the spring mech on the TB though. I know mine definitely does this, as when you change gear the needle doesn't drop straight away as the gunk on the TB is not allowing the spring to operate properly.

[coolrado 0]

If I put my foot under the accelerator pedal and pull it up she comes back down to just below the 1000rpm mark.

 

if the revs drop when you pull the pedal back up with your foot you need to try adjusting and lubing the cable, or if the cable still doesnt return back all the way you may need a new throttle cable or rubber grommet that the throttle cable hooks into on the pedal end, the throttle should spring back until it stops when you take your foot off the pedal and there should be a little bit of slack in the cable.

 

Yeah possibly... coulde be gunk in the spring mech on the TB though. I know mine definitely does this, as when you change gear the needle doesn't drop straight away as the gunk on the TB is not allowing the spring to operate properly.

My revs used to do this when changing gear as well and after i lubed the cable up it was fine, the spring return tension (at least on the G60 throttle body) should easily overcome the resistance caused by gunk around the mechanism, unless its seriously caked in crap, if it is give it a blast with some engine cleaner or a pressure washer and then soak it in some 3in1 oil.

a gunked up dry cable is very difficult to move though and will eventually wear through the sheath and fray or snap.

[Toad 0]

The throttle bodies also get sticky and unpleasant inside. Might be worth taking it off and cleaning it...

[boost monkey 0]

Ah thanks coolrado, some quality tips there!

 

Toad, why do TBs get manky on the inside? I can understand how carbs would as they obviously are in contact with petrol too, but TBs are "upstream" of the injectors so to speak!

 

I agree wholeheartedly though, the one on Ron is foul.

[Yandards 0]

Ah thanks coolrado, some quality tips there!

 

Toad, why do TBs get manky on the inside? I can understand how carbs would as they obviously are in contact with petrol too, but TBs are "upstream" of the injectors so to speak!

 

I agree wholeheartedly though, the one on Ron is foul.

 

Follow the engine breather hoses, one ends up over the top of the air filter (hence oily gunk on filter) and the other hooks up into the inlet manifold.

[belfastfumanchu 0]

Is it easy to remove the throttle body? Ive never done it before - any tips for doing it or things to look out for?

[boost monkey 0]

Cheers Yan :D

 

It's not too hard to remove the TB. Ideally you would remove the inlet with the TB on and then seperate the two parts, but this kinda increases the work, although that's how I did it purely due to the lack of clearance around the TB in situ (brake cylinder / servo etc etc)

 

the accelerator cable unhooks simple enough, although I think there's a few electrical connectors (idle switch etc) which are fiddly, plus on mine there's a bunch of small vein vacuum pipes underneath the TB aswell. apart from those, I think it's just the big black air intake pipe.

 

you'll want to get new gaskets for anything that you seperate from anything else (TB to manifold, upper manifold to lower manifold, lower manifold to cylinder head if you take this part off).

[belfastfumanchu 0]

Just for the record it turned out to be not what I expected. To cut a long story short she hadnt been running right on all cylinders for a while and I was due to get head gasket changed.

Got it changed and she now idles correctly again at just below 1000rpm. :D

[colinstubbs 0]

My idle has been dicking about, a bit low and grumbly.

 

Today I found the rubber elbow from black plastic tube to the TB has got a split in it,

 

Stealers want £51.36 inc VAT :shock: :shock:

i'll be looking at Stanford methinks........

[boost monkey 0]

My idle has been dicking about, a bit low and grumbly.

 

Today I found the rubber elbow from black plastic tube to the TB has got a split in it,

 

Stealers want £51.36 inc VAT :shock: :shock:

i'll be looking at Stanford methinks........

 

black gaffa ftw.

[colinstubbs 0]

Self amalgamating rubber tape seems to have done the job okay for now. Got to Stanford and back fine!!

 

I'm gonna have to mod the solid plastic pipe to get a better angle to the TB, may have to bite the bullet on the elbow in the end, it's cracking and will eventually break up. :(

 

Mind you if a new one lasts another 18 years that's not so bad!!! 8)