roll8221

boosted b18 overheating on acceleration... sputtering on deceleration found broken flex pipe which is before the o2 sensor.... my thinking would be leak pre o2 sensor would cause it to run rich but if I remember correctly lean makes it overheat....or does it? no oil in coolant... no coolant in oil... not losing coolant which I would imagine if the cooling system was building pressure from a blown head gasket it would blow the coolant out of the cap or create a leak at the weakest point... any thoughts?

fcm

Have you fixed the flex pipe and did that solve the problem?
If so, I'm guessing the flex pipe was the problem [specifically A/F ratio]. 94

roll8221

Not yet... Would like to narrow it down and make sure my thinking is in the right direction before i start throwing mo ey at it.... Id like to fix the drivability issue then move on the the next...

roll8221

Thermostat or temp sensor were my other two thoughts... Wondering also if i could try to take out the thermostat for a bit to see if jt improves and/or test the thermostat... I read somewhere that if the thermostat isnt the right temp it can cause problems and that many aftermarket thermostats are often at the wrong temp but im pretty sure mine is oem... Doesnt mean itz not bad though... Only has around 4k miles on it...

fcm

The ECT sensor if not working properly will effect A/F ratio, [rich when cold and leaning out as engine warms up].

The most common ECT sensor failure keeps A/F ratio rich, [all the time] symptoms are, easy starting when cold, [engine temp] poor starting when warm, poor performance when ART. very poor gas mileage.

Because of the overheating I would just replace the thermostat OEM Honda and good quality replacements are not that expensive, [easy to test in a pot of boiling water] less work to just replace it., running with no thermostat is never a good idea.

If that does not fix your problem, make sure rad fan is working then check water pump, they also ware out, pretty easy to tell if the water pump is working properly just buy looking into the rad through the rad cap opening, when thermostat opens, just under 200 degrees F the flow from the upper rad hose should be very apparent , [a "trickle" points to a problem] either thermostat is not opening properly, [less likely if it is a new one] or water pump blades are worn out.

A thermos gun should be used to see at what temp. rad fan turns on at, [also confirm rad fan is working].
Is it a full size rad, [you have not provided MM&Y of car, trim level and/or any mods]???

If there is a hole in the flex pipe it would also have to be repaired at some point anyway. 94