Hey!
My engine is behaving a little strange when cold (under 0 deg.) The idle is going up and down between 1000 and 2000 rpm. It also almost stops several times, and this continues until I have driven a few minutes. Anyone with a solution on this problem?
I also have a problem with the automatic heating control, I can't adjust the airflow. I suspect that there's a servo motor that might have broken down? Can this servo be reached from behind the glove compartment?
Cold greetings from Martin!
Cold engine problem
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Ivan Andhyiswara
Re: Cold engine problem
Dear Martin,
Your problem is a known problem according to my dealer in Holland. My engine (series III Turbo 16V) has te same problem, only it always happens, also in summer. The problem already excisted since the purchase of my Thema in 1991. I see the rpm-meter going from 600-1200 rpm. (Idle is 850 in my case with a warmed-up engine).
My dealer told me that the engine control unit (ECU) is set to "most fuel saving" without getting the engine to stop. It has something to do with cold oil and the fuel-intake valve. The valve reacts slower with cold oil. So the ECU sends a command to open the valve a little more but it happens too late. I had replaced almost every part of the enigne, including a new ECU and very expensive motor oil. It didn't change a thing.
One thing I remember from playing with a 2CV is that the air-intake valve caused the same problem. It was fully covered with dirt. After cleaning it, the eninge worked flawlessly. But a 2cyl 2CV eninge can be kept running by using tape and rubber band used by the mailman for his mail...
))
I have learned to live with this problem. Just keeping the throttle a little bit open when waiting for traffic lights the first 5 minutes.
Cannot help with your heating problem, hope someone else can.
Greetins, Ivan
Your problem is a known problem according to my dealer in Holland. My engine (series III Turbo 16V) has te same problem, only it always happens, also in summer. The problem already excisted since the purchase of my Thema in 1991. I see the rpm-meter going from 600-1200 rpm. (Idle is 850 in my case with a warmed-up engine).
My dealer told me that the engine control unit (ECU) is set to "most fuel saving" without getting the engine to stop. It has something to do with cold oil and the fuel-intake valve. The valve reacts slower with cold oil. So the ECU sends a command to open the valve a little more but it happens too late. I had replaced almost every part of the enigne, including a new ECU and very expensive motor oil. It didn't change a thing.
One thing I remember from playing with a 2CV is that the air-intake valve caused the same problem. It was fully covered with dirt. After cleaning it, the eninge worked flawlessly. But a 2cyl 2CV eninge can be kept running by using tape and rubber band used by the mailman for his mail...
))I have learned to live with this problem. Just keeping the throttle a little bit open when waiting for traffic lights the first 5 minutes.
Cannot help with your heating problem, hope someone else can.
Greetins, Ivan
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adam
Re: Cold engine problem
Can you tell me which model you have 8v or 16v is it a turbo or not,then i might be able to give you some things to try for your idling problem.The heater system does have servo motors which control the flaps in the heater box,you can get at these by taking out the instrument panel,but usually the whole dash has to come out because the drive on the end of the motor which fits onto the flaps are inside the heater box.This is not a very nice job!!!!!!!!!!.
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Daniel
Same problem
I have the same problem with my '92 Thema V6 automatic.
After cold start, the engine runs with aprox. 1.300 rpm, after 10-20 seconds it raises up to 1.700 rpm (always in "P").
If the engine becomes warm, sometimes it runs (correctly) with 900 rpm(P) / 750 rpm(D), othertimes too high with 1.100-1.200 rpm(P) / 900 rpm(D). From time to time the rpm in instable and varies between the values specified above.
My garage could not find any defect (of course, on this day the engine speed was correct).
Has somebody solved a similar problem so far ?
After cold start, the engine runs with aprox. 1.300 rpm, after 10-20 seconds it raises up to 1.700 rpm (always in "P").
If the engine becomes warm, sometimes it runs (correctly) with 900 rpm(P) / 750 rpm(D), othertimes too high with 1.100-1.200 rpm(P) / 900 rpm(D). From time to time the rpm in instable and varies between the values specified above.
My garage could not find any defect (of course, on this day the engine speed was correct).
Has somebody solved a similar problem so far ?
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Mike Peddie
Re: Cold engine problem
If your fan is blowing at full speed it means that the rheostat has blown.
If you remove the plastic cover at the back of the engine bay which covers the fan motor you can get access to the rheostat which is on the right hand side of the fan motor when looking from the front of the car to the back. You'll see some wires coming out of it.
The rheostat is in a black plastic casing about 12 cms long and 5cms wide with rounded ends. It can be pulled out, but I can't recall exactly how I did it. Easy to replace, but you'll need a new one unless you are a good electrician.
If you remove the plastic cover at the back of the engine bay which covers the fan motor you can get access to the rheostat which is on the right hand side of the fan motor when looking from the front of the car to the back. You'll see some wires coming out of it.
The rheostat is in a black plastic casing about 12 cms long and 5cms wide with rounded ends. It can be pulled out, but I can't recall exactly how I did it. Easy to replace, but you'll need a new one unless you are a good electrician.