172 ph1 Idle Issue

[Diggerdolan]

Hi as above, ive an issue with the idle on my ph1, It Idles fine from a cold start, once the engine warms up when put into neural or the clutch is depressed it Hunts from 1.5k to 3K and the resting idle is between 1700 to 3K. Even driving the car will accelerate to about 2500 rpm. I've pulled off the ICV and checked it, there doesn't appear to be any carbon build up or anything happening. This is the second time this has happened, it only seems to happen when the top inlet manifold has been taken off, I've checked all the connections and all the vacuum lines. Looking for any help really on where to look, or what could be the issue.
Thanks

 

[bloke]

air leak.

 

[Diggerdolan]

Air leak not cause the engine to keep revving up? rather than hunting then reving? dose anyone know if the diffuser seal would cause an air leak that would cause these symptoms?

 

[sugbug]

i had the same problem , it was the gasket or in my case mine had silicone sealent and was leaking air at the throttle body where the 4 bolts are attached on the inlet

 

[RS Charlie]

I'd also go with an air leak and there are a few sources for it IMHO on the 172. The main areas I would look at would be the manifold gasket where it joins the upper to the lower part, the sensor seals on the side of the manifold and the throttle body.

Getting a can of carb cleaner and carefully spraying it in the areas should help rule the areas out.

 

[Jekyll]

Have a look in here as I had similar issues and mine turned out to be the throttle body gasket.

http://www.cliosport.net/threads/ph...utch-is-engaged-neutral.778401/#post-10815841

 

[VR46-G@Z]

Mine was inlet gasket on my 182 after I fitted plugs and leads, new gasket on was spot on again...

 

[MeeBill]

Hi,
I'm a 172 owner from Hungary, having issues with my throttle body and i saw your posts, here i am asking and advice. What if my revs also fluctuate (between gear change, clutch on and fluctuate from 1000 to 2000) and idles too and high revs at the same time :smile: There is no gasket on it at all and the cable looks worn too, making the pedal hard. But also have a not original bolt drilled in to the cable "rack" oval plastic thing, pulled by a second spring, (made by the former owner to hold in position- also seen on other cars - ghetto mod i guess.). We strip it down, cleaned and understand that tha value in the throttle body is moving from left to right, like half a mm, leaving some space. When it is pushed by hand from the back side of the oval cable plastic rack, revs go to normal. Is it option to screw the bolts on the valve?

I know i had to change the cable and gasket too, but i think that is not the main problem. Looks like it the motion and lost stiffnes of the valve inside the throttle body.
Do you have any suggestion? :smile: What do you think, gasket, and a new cable could fix it or try to get a "new" tb? Found this in France for 200 euros, Original is over 300 as i saw. OEM numbers are ok.

http://www.dpauto.fr/boitier-papillon-7700871215-7700113290-7700113286,fr,4,60XR9.cfm

Now its ok becaulse that second spring handles idle to 1500 rev max, but damn its so frustrating when i kick the clutch, looking like a boyracer acting crazy.

Thanks for any advice,happy easter :smile:

 

[Jekyll]

@MeeBill Is this the issue's you have?

 

[MeeBill]

@MeeBill Is this the issue's you have?

Hi
On the one hand, this is it, yes! On the other hand, sometimes revs up like from 1000 to 2000 in neutral, like if i knuckle the gas pedal, but i do not touch it.
So there is 2 symptons, i guess the second one is somehow connected with air fluctuation. Note that, there is no gasket on the throttle body now, but i already ordered it. (just turned out when we put down the throttle body 2 days ago)
The main problem is actually the same as in the video you posted.

Thanks for help,
Cheers

 

[Jekyll]

Well in that's case, my issue was a knackered throttle body gasket which you've ordered. Mine was creating an air leak, thus having the issue in the video. A new gasket was ordered and problem was solved.

I was also having the same issue in neutral, like you.

 

[MeeBill]

Well in that's case, my issue was a knackered throttle body gasket which you've ordered. Mine was creating an air leak, thus having the issue in the video. A new gasket was ordered and problem was solved.

I was also having the same issue in neutral, like you.

Oh man, i would be more than happy if its like that, so simple As i examined the TB spring looked stiff, the casting was pretty clean, but the valve itself had a little backlash in the casting. That worrys me a bit, but i hope its simple as no gasket on it.
I'll be back and report which way cat jumped. ( hope i use this expression right)

Thanks for the help

 

[Jekyll]

Yeah post up in here once the gasket has been fitted, even if (fingers crossed its not) it doesn't cure it.