Bad fuel economy

taksepidar · Post by **taksepidar** » Fri Aug 10, 2007 1:14 pm

Hi
I got bad fuel economy on my Daewoo Cielo 97
I want start to check it with catalytic converter because I had misfire for 1 month and also some time bad smelling when I park my car any suggestion?

btw is there any English manual for my car?

thanks

jorge · Post by **jorge** » Sat Aug 11, 2007 2:39 am

For better fuel economy, you can replace: air filter, fuel filter, spark plugs, check the catalic converter. But in your car you have a misfire its posible product of a bad coil, or spark plugs, or spark plugs wires...

taksepidar · Post by **taksepidar** » Sun Aug 12, 2007 4:10 am

Hi
No I fixed misfire problem long time ago but I guess it damaged my catalic converter and so I have bad fuel economy now

BTW what is symptom of clogged catalic convertor?

Also does anybody know which of Holden Engine used in my Daewoo Cielo 97

cheers
john

jorge wrote:For better fuel economy, you can replace: air filter, fuel filter, spark plugs, check the catalic converter. But in your car you have a misfire its posible product of a bad coil, or spark plugs, or spark plugs wires...

Daniel · Post by **Daniel** » Sun Aug 12, 2007 7:51 am

taksepidar wrote:Hi
No I fixed misfire problem long time ago but I guess it damaged my catalic converter and so I have bad fuel economy now

BTW what is symptom of clogged catalic convertor?

Also does anybody know which of Holden Engine used in my Daewoo Cielo 97

cheers
john

Hi,

A defective catalyst has a rotted egg odor. And it will not undoubtedly pass any more the anti-pollution test.

Daniel

BosnianLanos · Post by **BosnianLanos** » Mon Aug 13, 2007 12:35 pm

Could very well be fouled O2 sensors. If you had a misfire, they'd be coated in black fuel residue. Take both out and clean them. Put them back in and see if it helps.

taksepidar · Post by **taksepidar** » Sun Aug 19, 2007 11:03 am

Hi
what is the best way to clean catalysis converter? just open it and wash with water or any solvent?

MMamdouh · Post by **MMamdouh** » Sun Aug 19, 2007 12:11 pm

i don't think CATs are washable/cleanable... you got to replace them.

MMamdouh

Andrew21 · Post by **Andrew21** » Mon Aug 20, 2007 12:39 am

MMamdouh wrote:i don't think CATs are washable/cleanable... you got to replace them.

MMamdouh

+1...That is correct.

Turtle_Wax · Post by **Turtle_Wax** » Thu Aug 23, 2007 11:05 am

Try it with the O2 disconnected and see if it improves. I've got a bad O2 and when connected the engine runs crap but disconnect it and it miles better.

taksepidar · Post by **taksepidar** » Sun Sep 09, 2007 9:56 am

but have a look at this patent:

http://www.freepatentsonline.com/6913026.html

Andrew21 wrote:
MMamdouh wrote:i don't think CATs are washable/cleanable... you got to replace them.

MMamdouh
+1...That is correct.

taksepidar · Post by **taksepidar** » Sun Sep 09, 2007 9:58 am

No in fact I test my O2 and it work fine as far as I can test it, if any one want to know I will tell how I test it.........

Turtle_Wax wrote:Try it with the O2 disconnected and see if it improves. I've got a bad O2 and when connected the engine runs crap but disconnect it and it miles better.

mezomaster · Post by **mezomaster** » Sun Sep 09, 2007 2:31 pm

How did u test ur O2 ??

daewoomofo · Post by **daewoomofo** » Sun Sep 09, 2007 3:16 pm

mezomaster wrote:How did u test ur O2 ??

good question, i didnt know they could test O2's

taksepidar · Post by **taksepidar** » Thu Sep 13, 2007 1:29 am

mezomaster wrote:How did u test ur O2 ??

First be casurefull of moving parts and electricity shock and make sure the engine is in normal working temperature

Usually o2 sensor have 1 wire otherwise refer to service manual to find out with one is ground and with one is positive and ...
while o2 sensor connected measure the output voltage with digital multimetre and it should jump between 0.1 and 0.9 or at least between 0.2 and 0.8 V rapidly this is the first test( in fact it is important how fast it jump but it is not possible to measure it with multimetre)

now disconnect the wire and while keeping one end of wire which go to ECU with one hand touch the Negative pole of battery with other hand and measure the output voltage of o2 sensor it should be fixed around 0.8 or 0.9 and you distinguish increasing in engine speed( in fact you fool ECU to rich the mixture)

vise versa touch the positive pole and o2 output should be around zero(0.1V) and engine is going to stop

I hope it was helpful and let me know if I am not right( because I did it long time ago)