A common problem but not sure what will be causing it.
I have just replaced the fuel lines as they were rotten. Whist I was in there I took out the throttle body, fuel rail, plenum and inlet. A good clean up and paint. Also removed the TPS from the throttle body whilst cleaning, not sure if this would cause an issue as the TPS is keyed inside to fit onto the shaft of the butterfly valve so it will only go back on as it came off. (not sure how to set TPS up)Gave the ISCV a good clean with carb cleaner.
All back together and the car started up no problem at all but it is idling at around 1200 rpm.
I haven't ran the car properly for quite a while so I cant remember what is might have been previously!

So, I have disconnected the ISCV when warmed up which made no difference. Car starts and runs at around 1200 and when warm idles at 1500. Removed the hose on throttle body to make sure the butterfly valve seats properly and its ok.
The car does not hunt at all but does pop and fart a bit from the exhaust. Idle screw on the throttle body has never been touched.
car is totally standard.

Any offers on a diagnosis please.

Ta.

 

Have you put new gaskets on?? You have to put the TPS on right though and adjust with the small screws/allen bolts either side of it. Can do it if you have one or a mate with a SECS monitor. Did you take the ISCV apart?

 

TPS is fine, the problem is there is an air leak, as said, did you use new gaskets?

Martin

 

I used a new gasket on the plenum chamber. The rest were in fairly good condition and I was really careful assembling it all back together.
I didn't take the ISCV to bits.
The car seems to struggle a bit when pulling away in first gear and needs to be revved to get it going.
Should I go around all the joints with some carb spray to try and find an air leak?

Out of interest, how do you set the TPS.

Many thanks.

 

Did you clean the inside of the throttle body around where the butterfly seats? Removing any carbon or the coating inside the throttle body might have caused an air leak.

 

Yes mate, everything I took off got a really good clean up. I have checked the valve though and it looks like it seats properly when its shut.

 

That would be a good place to start. Re the TPS, you have to calibrate it so the voltage is circa 0.5V with the throttle closed rising to around 5V at WOT, but like I say that isn't your issue.

Martin

 

Strip the ISCV and see if it helps. http://bbs.rsownersclub.co.uk/showth...post2732119622

 

As martin says, it's an air leak. Carb cleaner or easy start round all the joints should highlight it. Either that or you will need to pressurise the inlet somehow and spray some soapy water around the joints.

 

If you have cleaned a lot of carbon out of the idle screw bypass channel and around the throttle butterfly I would EXPECT the idle speed to have risen. It may just want resetting now, along with a co screw adjustment. That's not to say you don't have an air leak given your suggestion that's it's accompanied with running issues, but worth bearing in mind.

 

Thanks folks, i'll check it out and report back.

 

Sorted.
It was an air leak on one of the injectors, I could hear it hissing quite noticeably. The 'O' ring was shot, I had some spare correct type. Once changed it made a difference straight away, now ticking over nicely.

Job jobbed.

Thanks all for the top tips.

 

Well its been laid up for a while but MOT passed today.
Get in.

 

Nice one.