williams engine idle problem

[schakal]

williams f7r engine , no catalytic converter or power steering .
2" stainless steel exhaust system .
engine runs great and pulls like a train .
but sometimes it will idle like this in the video , but once
the water temperature is around the first line on the gauge
everything is fine.
any ideas why its doing this ??

[Merijn]

Hmm... This problem is pretty common, I believe. There are definitely people here who can address it. Unfortunately I can't help you.

Good luck solving!

[tutuur]

Why do you want to solve this? Sounds awesome

Try to check the whole ignition part. Maybe when the engine is cold the spark plugs have more trouble igniting the gas mixture...

Edit: can you help me with something? I'm going to build a f7r engine into a 9 this week but need some help with the wiring.

Where is the head engine connector and which pins did you relocate to get it properly working with the f7 ?

[Robke]

Sounds like it's running on 3 cylinders when idling.
What's the state of the spark plug leads, distributor cap, rotor and spark plugs?
I've always prefered an original distributor cap and rotor as my Clio always seemed to run smoother with these original parts, aftermarket was rubbish somehow.
Maybe as time has progressed the quality has been bettered since I don't own a Renault anymore for over 5 years.

[Geert]

mate of me had this on his valver. after replacing the engine loom and injectors the probleem was solved. i think it was a grounding problem.

[Merijn]

I think it's worth trying to fit some new cheap parts, like Rob wrote, before investing in all kinds of expensive stuff.

[Jeff rsi]

Do you have an open air filter?

I've had this problem with 2 cars after fitting an open air filter.

[Martijn Kool]

tim has the same problem..

it sounds like 3 cilinders, but it ain't Rob.

I replaced the mass connector cables, it did help, for exactly 1 day, which was just enough for the APK (dutch MOT). got the car back and suddenly same problem again.

I tried refitting the mass connector cables, but this was not helping anymore. maybe it has something to do with the injectors, because I've heard Mike got this solved after changing the whole electric shit from the motor AND inserting other injectors.

strange thing was, he had this only with cold motor, but was getting worse, last time I checked it stopped when the cooling fan was going ON, precisly at the same time. This almost says that is has something to do with electric shit....

weird F7x problem it is. I cannot imagine that is has something to do with an openairfilter

[Tom]

Mine does this also but only sometimes. Only now ant then and only with a complete cold motor. My engine is bonestock and fitted with oem parts.
To be honest I don't give a fuck becease it only appears for a couple of seconds and only if you let it idle while freezing cold. If I drive 100 meters and let it idle again it doesn't happen any more.

[Martijn Kool]

you will give a fuck when it keeps squirting till the fan goes on...

[Geert]

mike had it also with a warm engine. always for the first 2 minutes.

[Tom]

A car is made to be driven, so after starting you drive away and the problem is not that big I supose. Could it be something with the cold start injector?

[Haas]

My F7P in my 19 has exactly the same, but not frequently. My idea is that is has to do with the (geen idee hoe je stappenmotor vertaald?! ). When I cleaned it, it was away for a pretty long time ans as you said yourself, it only happens when the engine is cold...sometimes.

[Geert]

well by mike the car was almost undriveable for the first 2 minutes. so its really annoying for small distances.

the cold start injector could be the problem, try to unplug it for example.

[-jo-]

My F7P in my 19 has exactly the same, but not frequently. My idea is that is has to do with the (iddle air control valve -IACV ). When I cleaned it, it was away for a pretty long time ans as you said yourself, it only happens when the engine is cold...sometimes.

[Haas]

Tnx

[schakal]

thanks for the replies

mine does it for the first 5 minutes from very cold .
when driving i can feel the power is going down slowly but as
soon as i dip the clutch pedal revs go up to normal . so it has got
something to do with the engine being under load !!

-i have changed the idle control valve ,problem is still there .
-i have magnex red leads ,they are brand new .
-open filter but i dont think thats the problem.


i also have another problem , i am not sure if they are related .
when i drive the car hard over certain revs (5-6000 ) it will
start idleing at 2300 rpm and it wont go down untill i turn the ignition off
and restart again than it goes to idle at 950 rpm .
its very annoying when you are sat at the traffic lights with
your engine revving 2300 rpm

i have an idea my problem might be related to throttle position sensor
but i have not found another throttle body to swap over and see yet

[jacques]

The idle proplem is stil your idle air control valve. Have you tried to clean it ultasonic. Only put the valve, not the coil, in the cleaning liquid. After cleaming lubricate the inner valve bdy with some WD40.

Re. your TPS. The voltage over your TPS should be between 0,12 and 0,16 volts in closed position. (when fully opened it should be 4,7V). Measured over the red wire and the green wire. If you play with the lever of the TPS and the engine does not respond, the TPS is dead. Here is the description in Dutch, but with pictures
http://www.team1916vforum.nl/viewtopic.php?f=23&t=214

[Maarten-Jan]

Also, the 2300 revs idling problem after high revs is related to the cable behind your speedometer. This cable tells the ecu whether the car is still driving or not. The cable is attached to the speedo cable.

[Roald]

Also, the 2300 revs idling problem after high revs is related to the cable behind your speedometer. This cable tells the ecu whether the car is still driving or not. The cable is attached to the speedo cable.

Correct, it's connected to a hall sensor and that tells the ECU what the vehicle speed is, so that 2300 rpm issue could mean the sensor died or a bad contact.

[Martijn Kool]

true but the speed sensor should keep the rpm around 1300, not 2300!

[schakal]

guys i had this 2300 rpm problem for a while now , i know
a lot people say its the road speed sensor on the speedo cable or
the black wire is not earthed properly .
i have earthed the wire twice and even changed the speedo cable
with a brand new one to eliminate this . the problem is still there !!!

so its not the speedo cable i am afraid .


i will check the tps readings with multimeter though ,thanks

[jacques]

Can't you borrow a good idle air control valve from somebody in order to find out if your valve cause the problem is.

[Ronald1916V]

Try another lambdasensor.