bouncing idle

[JR]

got my 19runnibg again, first time sine mid october, startedon bout the 5/6th go

But it do't idle right, started high 1400 ten after keeping the revvs up at 2k for a minute it bounces from 950 to 1400. Also sounds like a whining/squeeling possibly from throtle bodybut could be new cam belt/aux belt.

scuse the typing, it's not my usual board,

Ta

 

[JR]

oh i read about this before but i can't recall what the issue was, anything to do with it sitting and drying out for 4 months?

Clutch feels odd too but not tried to engage a gear yet as i'm a bit cautious as the car is squeezed in the garage and i don't want it to lurch off!

 

[tob123]

CTS?

http://www.retro-renault.com/forums/engine/7458-cts-coolant-temperature-sensor.html

 

[Chris H]

indeed CTS.

If you had also held the revs up a bit longer it would have probably settled down to a nice idle.

 

[JR]

nice cheers. i'll give it another go before splashing out i've spent too much on it lately. Back in 10 days so it can wait.

 

[f7r]

if there is a wheezing noise too could it be worth checking for a leak on the iac valve?

 

[Chris H]

the wheezing noise is the icv trying to supply enough air to keep it going.

 

[JR]

so it hasn't gone away sadly. Tried running with the sensor unplugged but no change.

should i replce it anyway or could there be another cause?

 

[JR]

ordered from GSF for £10.20 inc del

why does the coolant temperature being off cause the idle to bounce 500rpm?

It has destroyed the economy. 100 miles taken half a tank! I need this sorted.

Will it affect economy on the motorway too? i'm planning on driving 130 mile sat and 85 miles to ace cafe and back monday, could be £75 of fuel at that rate!!!

 

[tob123]

are you keeping it unplugged?

a faulty cts makes the ecu thinks the engine is cold even when its warm so its supplying an enriched mixture of fuel,

 

[JR]

it varies, on a gradient with a warm engine it was at a steady 1300rpm then if warm it can either bounce between 1300 and 1550 or 950 and 1500 - all with it plugged in. It didn't seem to make any difference unplugged when it idled but that was without driving it atall. it will be unplugged until i replace it now

 

[Chris H]

with it unplugged it defaults to as hot engine

the idle speed bouncing says the lambda isn't switching fast enough. if you unplug the lambda ity should stop the surging if not then you need to get someone competent to look at it.

unplugging the cts and leaving it that way will save you fuel unless the lambda is faulty which it sounds like it is.

 

[JR]

with it unplugged it defaults to as hot engine

the idle speed bouncing says the lambda isn't switching fast enough. if you unplug the lambda ity should stop the surging if not then you need to get someone competent to look at it.
unplugging the cts and leaving it that way will save you fuel unless the lambda is faulty which it sounds like it is.

now where's the fun it that

 

[JR]

if i'd attached the cts connect upside down could that've shorted something?

 

[Neal R19]

no

 

[jaser19]

my 19 surges if it isnt run for a while but if it gets run daily its bang on

 

[JR]

this problem is like rythmic pumping of the accelerator, get funny looks from padestrians at crossings etc.

 

[bidderman1969]

tried an ICV yet?

 

[bidderman1969]

or unplugged the lambda?

 

[JR]

tried an ICV yet?

no, need to get one- missed one on ebay for 15 posted, was one in my watch list a while ago, looked mint and went for a fiver:roll:

or unplugged the lambda?

yes, no change, i'll try again tomorrow as i can't remember if i'd also unplugged the icv (should i?)

Cheers