No steady idle - Saxperience

Spendyrx · 14th April 2016, 17:16

No real problem with the idle but it doest stay steady, it seems like every half second it fluctuates between 750 and 900rpm. Not that bothered and the car's so quiet it's barely noticeable but just wondered if anyone knows what's causing it. I'm guessing it has a dirty throttle but being lazy and not investigated yet

Shadowslayerzz · 14th April 2016, 17:26

Hi mate, and that to me sounds like a dodgy icv (idle control valve) there's a guide on here that shows how to clean throttle body and also has pics of where the icv is located so worth taking a look at that, possibly replacing with a new or decent condition one see if that helps

Spendyrx · 14th April 2016, 20:05

Cheers, I've seen the post somewhere along the way.
Luckily for me I have a magnetti marelli one in the shed I can try as it came off a 206, I'll check the part no.s and hopefully they're the same.
I'll get that icv intake a wash first and take it from there.

Synister · 15th April 2016, 11:02

Is it an 8v? If it is, I spent literally hundreds chasing my idle problem until Chipwizards (I still owe him a pint!) on here told me to check my valve clearances. Sure enough they were all far too tight and none were in spec. Once they were all adjusted it runs like a new car.

Stissy · 15th April 2016, 12:39

Quote:

Originally Posted by Synister

Is it an 8v? If it is, I spent literally hundreds chasing my idle problem until Chipwizards (I still owe him a pint!) on here told me to check my valve clearances. Sure enough they were all far too tight and none were in spec. Once they were all adjusted it runs like a new car.

Hi mate. How did you do this?

Gandi699 · 15th April 2016, 12:47

Quote:

Originally Posted by Stissy

Hi mate. How did you do this?

using feeler gauges between valve stem and tappet, slacking lock nuts off and adjusting the tappets themselves with a flat blade screwdriver so the clearances are reduced or widened. Guide:

http://www.saxperience.com/forum/sho...usting+tappets

Spendyrx · 15th April 2016, 19:18

Tidy, very good shout!

Spendyrx · 15th April 2016, 19:20

Explains the tappety tap too

Spendyrx · 18th April 2016, 06:58

Had a go at adjusting valve clearances, was a nice easy job but not so much luck. I also cleaned icv.
Although it has eased I think it's just a little lumpy because it either hasn't been serviced well in the past or where it's been stood for a long time it's just not done it much good.
It sounds like a 1.3 endura (fiesta chain) engine!
So...... From here, I'm just going to drop in some hydraulic lift treatment/emissions reducer to see if that will ease it but if not then I'm just going to leave it as other than that the car runs great and I'm not spending any more money on it

Chipwizards · 19th April 2016, 01:42

Is it just me or does it make you really thirsty reading this thread?

Anyway, your idle fluctuation could be down to a slow lambda. If it is slow to respond the mixture goes too far from lambda-1 before the ECU 'sees' that it has. When it goes lean the engine will slow down a bit. Going rich doesn't usually bother it until it's very rich.

I suggest you put a multi-meter or 'scope on the lambda.

Put the red wire on your meter to the black wire on your lambda and the black wire (on the multi-meter) to the grey wire on the lambda.

You should see the voltage go from around 0.2v up to 0.8v. The key thing to look for is whether the low voltage reading corresponds with the engine running slower and vice versa. There is a slight delay because it take an amount of time for the gas to get from the cylinder to the lambda but if the frequency of the speed change matches the frequency of the voltage change then that's your culprit.

strato_vts · 19th April 2016, 15:11

Quote:

Originally Posted by Shadowslayerzz

Hi mate, and that to me sounds like a dodgy icv (idle control valve) there's a guide on here that shows how to clean throttle body and also has pics of where the icv is located so worth taking a look at that, possibly replacing with a new or decent condition one see if that helps

Hi, I don't find the guide about throttle body cleaning... can you please send me the link?

Thanks a lot

Spendyrx · 19th April 2016, 17:58

Lol thirsty, you could try wash it down with some redex if you like

Thanks for the advice, I'll try it the weekend, just picked up a tu1 for 30 quid so got some spare lambdas on that. Well happy as its got everything, ecu, starter, icv,tps the lot

I'll send the cleaning icv link in a minute, my phone is being a pain and not pasting the link!

Spendyrx · 19th April 2016, 17:59

http://www.saxperience.com/forum/sho...d.php?t=174710
There ya go buddy

strato_vts · 20th April 2016, 07:58

Thanks Spendyrx!