Hi,
I wrote earlier about some problems which i fixed in the meantime (EGR, IACV cleaning, complete tuneup), but I have one bigger problem since I bought it.
When the weather is hot, over 86 °F/ 30°C the engine starts to lose power, sometimes even feels like choking or driving with a pulled up handbrake. The fuel consumption goes over 11-12 liters/100km (23mpg), no matter city or highway driving. When its colder, it gets better but either way not normal or good enough. It starts losing power after driving for 10-15 miles, when the engine warms up totally. (no overheating)
There is no error code from the ECU, two different honda repairshops didn`t find anything wrong with the engine.
I tried to disconnect the first O2 sensor to see if there is a difference (with ecu reset), but no difference, the check engine light comes on and the engine acts the same way. (the O2 sensor in europe costs 370$, that`s why I didn`t buy one to test it)

So, if anyone have an idea...

I bought the car 3 months ago and I don`t know anything about his past, except that it looks like a new one, driven in netherland.
The model is made in UK, model CH6, F18B2 engine.
Excuse me for a bad english, I`m hungarian.

 

sounds alot like you O2 sensor... maybe you know someone with a scanner?

 

So it can be that the sensor is failing but the ecu doesn`t give an error code yet?!
What kind of scanner, for O2 sensor or ECU scanner? I`m not familiar with these terms yet. Honda dealers are too expensive, it`s like 100$ just for checking the ecu codes, so I`m trying to find an alternative solution. I have a friend with honda repairshop and diagnostic equipment, but obviously he doesn`t know how to find the problem.
I was thinking, if the O2 sensor sends incorrect values, can I connect an enhancer to correct it?! Does it worth a try?

 

ECU scanner would show how the O2 sensor is performing or you can try to measure the output voltage from the O2 sensor.

 

Try replacing the main relay.

 

I found the problem, it was the EGR valve, it looks like too much exhaust gas went thorugh it and the engine didn`t get enough O2. Now i blocked the valve totally with a part of metal, and the engine runs perfectly.

I cleaned the valve and the ports earlier, back then it helped with the power at low rpm-s, but when the hot weather started it caused another problem.
At the bottom, where the valve opens and closes, there is a moving part with an inbus ending and when I was cleaning it, I tried to unscrew it, but I couldnt get that out, I just rotated it in both ways without loosing it up or something. I don`t know if I was damage it with that or just loose up the valve strength, just sharing my experience..
So if anyone knows why is there an inbus ending, is it for some kind of setting or just for one-time assembling?!

(In the meantime I tried to change the O2 sensors, exhaust, converted to LPG and none of them made any difference, after all that, there was a few things left to check... )