okay heres the deal. please any help or input is much appreciated.

i have my car for over a year and over 20xxx miles on it, the clock sit at about 77xxx right now.

i just did a rebuild about a month and a half ago.. new head, new valves, new retainers, machine work, etc.

along with that i got the spark plug recall down, got a new catalytic, put a new air filter in yesterday, did an oil change last month (castrol gtx high mileage), and my result is.

1) crappy throttle response - i mean its bad.. feels so sluggish, i have a VAFCII (untuned) which i monitor my throttle %. say i apply 15% throttle, the climb slowly climbs to about 4K RPM, then picks up.. kind of like turbo lag.. like i hit a baby vtec in the RPM band. VTEC over feels fine, but i can say ive never felt such a transition than before, kind of weird? yes the throttle cable is nice and tight according to specs, and i just dropped in a new filter.

2) MPG - usually i used to get around 250 miles to a tank, few vtecs here and there and about 60% freeway and 40% city driving.. now im getting 200 miles and only 2 bars of gas left? i dont understand? i just did a tank, no VTEC, 80% freeway and 20% city driving and i got 205 miles??? i dont know what steps to take from here. i always pump 91 gas, and i just used fuel injector cleaner about a month ago during the rebuild.

3) oil consumption - with my horrible 200 miles a tank, im finding myself having to fill a half a quart of oil per tank? it shouldnt be that much? before my rebuild, it was maybe a little here and there, and i would probably go through a quart and a half between oil changes but not this much oil. i dont what this could be?

all in all ive taken the precaution steps. ive talked the mechanic who did my rebuild and have had the valves adjusted, ive done the MAP whack for a temporary cure with no significant change, reset ECU plenty of times, did the air filter, brand new plugs from honda, new catalytic, and new head.

does anyone have any idea where to go from here? im not sure if the problem can be fuel related since the throttle response, MPG, and oil consumption can all be related to fuel. please someone help, or give any input.

thank you for your time.

 

I would first suspect the rebuild didn't go so well. Something may not have been put together right. Cam timing could be off. Have you tried a new MAP sensor? What about the injectors? Were they checked out when they were out? During the work, were they taken care of or just tossed into a dirty box? Could other parts that came off during the work have been badly treated?

Why was it rebuilt? Your oil consumption is SEVERE. If the valve work was needed, maybe there was other damage that wasn't addressed?

 

ive been meaning to get a new MAP sensor, but i thought the MAP whack would provide a temporary solution. and since i havent seen any difference in all, i just put it off. will purchase at then end of this week.

as for injectors, the mechanic who worked on it said they were fine. after the rebuilt was done he said he had done another compression, vacuum, and fuel test and the numbers were back up.

i know the mechanic well, and he treated my car as he would his own. so im sure he had put much car and priority in my car as i would like. but if this problem cant be solved by me, i will definitely go back to him.

the reason for rebuild was bent valves.

so things to tell the mechanic to check if i cant fix the problem.

-cam timing?
-recheck injectors, fuel pressure, vacuum, another compression test
-valve adjusting??
-what else?

im going to check my plugs today, just for the hell of it. make sure they are gapped (which they should be since i got them from the recall), and torqued to spec.

thanks xviper. any other input would be great.

 

You're going through a qt. of oil every 400 miles. I think it would be useful to find out where it's going. It can disappear in one of several ways. If it's leaking, then this would not affect performance but it's still a nuisance. If it's due to bad rings, this should be addressed and should have been discovered when the engine was apart. If it's due to bad valve seals, this too, should have been addressed when the engine was apart. Has a leakdown test ever been done? This may tell a tale, too.

 

okay i will request for a leak down.

hmm, i thought a compression test included a leak down.

what exactly happens in a leak down test? checks for leaks?

 

It should and is easy enough to do but some mechanics don't take the extra time to wait. A compression test tells you if the cylinder can achieve a certain pressure. A leakdown test tells you if it can hold it. Each parameter will tell a different and specific story.

 

could it be possible the oil im using is just complete $hit?

Castrox GTX High Mileage - 10w30

hmm.. maybe go back to Honda Oil?

 

I don't think so. Castrol makes pretty good oil. Besides, the "Honda" oil is (or used to be) just a Mobil Drive Clean. Nothing special.
If you were using something like a 0W20, then I'd say maybe take a look at the oil, but not in this case.

 

I agree with the leakdown as Viper stated! Once the cylinder is charged the mechanic can use a scope to pinpoint if any air is escaping - for example if you have exhaust valves that are leaking you can hear it out of the exhaust and the same for the intake valves and the intake manifold.