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2000 Honda Civic 4 cyl Front Wheel Drive Automatic 105000 KM

i have a EK3 - D15Z4 Engine with Automatic gear box.... but it does only around 28.72 miles to the gallon in the City. I'm not a rough driver & i do not come across any traffic @ all (the route i take daily).

I purchased the car around 3 months back & even then it was the same....

The car has not been modified & runs on the standard wheel size as well.

i have now replaced the timing belt, fuel filter, air filter, oil filter, cleaned the injectors, Engine tune-Up, oil change...

Could you guys help me solve this issue ?

 
Rep Power: 244

Well, here are a couple of possibilities and yes, a d15 *should* get much better mileage. Try these in this order: 1. Driving style. If you coast as much as possible while in gear, the fuel injectors actually shut off which results in higher mileage (when the engine is above 800RPM if memory serves). 2. Check your ignition timing as it may have been set slightly too retarded and would cause poor fuel economy. 3. A bad primary oxygen sensor can drastically affect fuel mileage. As low as 15MPG can be had without any CEL's on OBDI cars and I'm sure it could negatively affect these newer cars as well.

Let us know what you find.

 
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hi... thanks for the suggestion... i will try it out & let u know....

 
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hi... i got the Oxygen sensor checked & it was ok....the agent plugged the Diagnostic Computer & did a full check. They said the Injectors are opened for too long (when idling it should be around 2.7 - 3.1 ms) but mine is around 3.5 - 3.7 ms and there is nothing that they can do....


What are my options ???

 
Rep Power: 204

Wow! That sucks. I hope you get this resolved. I'll be keeping an eye on this thread.

 
Rep Power: 244

Chris: I'd try a bottle of Techron Fuel System treatment. I've run the 12 oz. (to treat 12 gallons) bottle on less than 1/4 tank and drove it until it sputtered before filling the tank with no ill effects. A friend bench tested some seriously old Honda injectors after soaking them in the stuff for a few hours and they flowed to factory spec. and all practically at an identical rate. *Shrug* Hope that helps.

 
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Thanks for the suggestion.. but we do now have Techron Fuel System treatment in this country... we do have the X1R & 3M products... do u have experience with them ?

 
Rep Power: 244

Chris: No, I do not have experience with them. 3M generally makes very good products, I would try their fuel system cleaner.

 
Rep Power: 811

ive heard good stuff about 3m. check bobistheoilguy.com forums for additive info. there are some that are better than others. my favorite is lubecontrol.com