The motor is a rebuilt b17a w/ 11:1 compression, otherwise all stock. I'm running it w/ an obd0-->obd1 conversion harness from blownhatch and using the stock p61 ecu.

There is random hesitation/bogging below 5k, sometimes its there, other times not. And exactly where in the rpm range it happens seems to vary as well.

In addition there is a substantial, yet short bog when i hit 5k. this happens every time i hit 5k....excet it seems like it might not do it when the motor is cold. typically i don't rev the motor that high when its cold, but one morning i had to in order to merge safely....and it didn't bog.

there isn't any hesitation above 5k. and vtec doesn't seem to be engaging anymore either (probably not related).

So far i have tried:
-new O2 sensor
-2 stock p61 ecu
-2 sets of injectors
-2 map sensors
-2 IAT sensors
-new coil
-new cap and rotor
-2 igniters
-2 stock fuel pressure regulators

Is there anything else that could be causing hesitation? I've tried everything I can think of.
thanks.

 

bump

 

How's your exhaust, I had a similar bogging problem that was cleared up when I got a better flowing exhaust.

 

the exhaust is stock, but the stock integra exhausts are decent, that shouldn't be a problem considering other than the compression the motor is stock. oh, and I also checked the cat and its not clogged, so thats not the problem.

I checked today and i was right about the temp thing. It doesn't hesitate at 5k when the motor isn't quite up to operating temp.

 

any suggestions?? i'm desperate to find out what the hell is wrong w/ my car, i've tried everything i can think of.
tia.

 

Could be misadjusted valves, maybe spark plugs and wires.... tried those?

 

Are you throwing any codes?? A bad or a badly wired knock sensor will not let you rev past 5k or 4.5k. Does a B17 even have a knock sensor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. S &raquo;</TD></TR><TR><TD CLASS="quote">...maybe spark plugs and wires...</TD></TR></TABLE>



with hesitation, first thing you want to check is your ignition system, if you have gone thru everything and still hesitates, as a last resort you might want to go buy thos spark plug things direct hits, that way you know for sure ignition is ok.

 

The valve are adjusted properly, i've done it twice already. I've also used 2 sets of new plugs, so i don't think they would be the problem.

the motor revs pas 5k, it just hesitates right when it gets there...so the knock sensor isn't the problem. I know thats wired properly too.

No, i'm not throwing any codes, and haven't the entire time the motor has been in the car (and i know the cel system is functioning properly because I checked it). Plug wires were going to be the next thing i was going to try, i just need to get some $$ to buy them. what are these "direct hit" plugs you are talking about? care to elaborate, or link me to something?

thanks for your input guys.....keep it comin!

 

unbolt the exhaust and see how the bogging feels then.

I've got some insane bogging with my h22 from my exhaust (actually an exhaust leak/bottleneck).

 

could you talk a little more about why the exhaust could be a problem? Its a basically stock motor, so i don't see how the exhaust could be causing the hesitation problems, but thats the second or third time its been recommended to me that I check it out. I definitely could be wrong, so i'd like to learn more....i'm hungry for knowledge so don't be afraid to dish it out.

Oh, and i've tried 2 different exhausts (both stock) because my original one had a fairly large dent in it. I noticed no difference in how the motor ran when I swapped exhausts. Also, the fact that the hesitation only happens when the motor is warm sorta makes me think the exhaust isn't the problem.

 

bump

 

i'd def. check ur ecu if ur vtec isn't engaging that would be where to start at, not quite sure why it hesitates at 5k try to figure out why ur vtec isn't engaging first it might solve the prob. just a suggestion...

 

good point about the vtec before the other problem. thats actually where I was headed since i'm not getting any good places to start in regards to the hesitation.

over the weekend i checked all the pins on the ecu and they are all wired up correctly, including the ones for the vtec solenoid.....i already knew it was hooked up right because it was previously working...but i figured i'd check anyway.

also, about the ecu. I've tried 2 stock p61's so i know the problem isn't the ecu.
thanks for your help...any more input?

 

umm check ur wiring harnest it might be that, im not quite sure tho...

 

like i said, i checked the wiring and its all hooked up like it should be. I used the continuity tester on my multimeter and checked every pin on the ecu.