Technical marea stalling 1.6

Currently reading:
Technical marea stalling 1.6

jamgeo

New member
Joined
Nov 25, 2004
Messages
15
Points
5
I have recently aquired my second marea this time a 1.6 gas conversion which stalls when warm (on gas and petrol) the gas is single point injection, it stalls on either when hot it will allow the revs to come down for about three seconds and then dies. if you keep up the revs its ok. it drives fine through the rev range apart from idle. i have tried a new idle cotrol valve.
any input would be gladly received.
 
Thanks Polecat. I've had the plugs out and they do seem over 'sooty' but car runs o.k in rev range above idle. It also starts fine from cold but as soon as it warms up it dies at idle, as if shot. it doesn't stutter or hunt it just cuts out. Ive read threads on idle control valve which has already been eliminated, and lambda which is my current suspicion. the injector light goes out as it should, and on cold start it runs at about 1200 rpm and eventually drops below 1000 at which point it refuses to idle. all the above relate to the petrol cycle but it does the same on gas. I realise the temp sensor could be the cause but wouldn't this stop the engine altogether and not just at idle?
Thanks
 
Sooty plugs indicate the following;
Rich mixture
Weak ignition
plug type too cold
faulty or blocked injectors
fuel pressure problems

My first bet would be the temp sender as the engine starts ok but chokes when warm but you get fuel backoff to cut the revs. So this would indicate that you could have a problem with the lambda as that is the other main sensor that controls fuel feed.

Check the vacuum pipe to the fuel pressure reg, if it has fuel in it you have a perforated diaphragm.

Injectors next, try a fuel additive and/or bleeding them.

Check you have the correct plugs.

Hope that gives you something to work on.

Good luck.
 
Last edited:
Ive had a couple of hours on this car and the following is now happening:
if i short the terminals of the cts the engine will idle happily, albeit at about 1100 rpm. the new problem is that as the accelerator is pushed down the engine misses mid range. It is obviously overfueling and the plugs, if taken out after a short period of running (5 mins) are sooted up to hell.
any offers of advice (could the ecu be at fault?)
 
Yes lambda checked, been reading and I'm thinking that it may be down to the tdc sensor. From what i understand the coolant sensor looks after the fast run (choke cycle until the engine is warm). After which the idle is looked after by the tdc sensor. I'm assuming that the impulses from the tdc sensor look after both fuel and spark, this is my next plan of attack.

Sooty plugs
Won't idle when warm
Misfires through mid rev range

Starts first time from cold :bang:

BTW does anybody know anything about 'open/closed loop'
 
Forgot to add managemant light is working and does NOT illuminate whilst the car is running! :cry:
 
Not much you can do about the tdc sensor. It will be either external near the flywheel low down or internal fitted into the block near the flywheel at the front. Internal gap 0.5mm to 1.5mm internal 0.8 to 1.5, these are not adjustable, (officially).

Open closed loop is to do with how the lambda affects the fuel supply. In a closed loop the lambda senses oxygen in the exhaust and sends signals to adjust the fuel flow which the lambda senses again....hence closed loop. In open loop the ecu uses a fuel map without using the lambda.
Some cars use open loop until the car warms up and then switch to closed loop once the car reaches operating temp.
The lambda may also have its own heater element.
 
just to add. i've now tried the ecu +key +block on another marea 1.6 and it works fine???????????????????
 
Not replaced tdc sensor yet but will do. It seems to me that this engine is refusing to idle in closed loop mode. from what evidence/advice we have so far and the research i've done myself it can only be tdc, coolant temp or lambda sensors. Unless of course there is a wiring ussue going on somewhere. Stick with me, we'll get it sorted in the end!!!!!!
 
I've now checked the resistance of the tdc sensor and found it to be 1021, Ive checked a known good unit and it reads 620. Could this be my problem??????. What is the correct range??
 
Yes that could be the problem, the resistance can increase with age. It could be that when it warms up the resistance becomes too high and the ecu starts missing pulses.

I don't know the resistance for that tdc but I would expect the reading to be less than 1k. Usually between 300 to 800, poss 900 ohms.
 
Amazing!!!
Not fixed but have tried (while car is running, taking the electrical plug out of the idle cotrol valve and the bloody thing will idle (950 rpm) all day long. obviously this isn,t car fixed but it now seems that the idle control valve is receiving duff info. My tdc sensor hasn't arrived yet but i think that the wayward info is coming from this little fella.
One point of interest is that the engine dies if you put the heater on max!!!!
I would guess that this is the point at which the ict would allow more air in and keep idle stable?

keep em comin!!!!:rolleyes:
 
Back
Top