aavtec

I'm trying to diagnose what I could only describe as a misfire but don't believe it is. Whenever I rev past 5500 rpms my car bogs and sounds like its misfiring and loses power, It only happens up top. So far I've tried 3 different ecu's and replaced the spark plugs. So today I was taking to my buddy about it and he thinks it may be worn valve guides. When I thought about it, it makes sense. If the guides are worn then the valves probably wouldn't seat properly when rotating at 5500k per minute. I've done a compression check and all 4 cylinders were no lower the 210 psi. Any thoughts?? Motor is a JDM B16A

Deksinjo

Are you have cell light ?
Compression is ok so valve,rings,pistons are ok...

94civiccupew/b7

^^ i'm with this guy. your compression sounds about right. you said you changed your plugs. did you change your cap and rotor as well? what about your coil? maybe try and find someone to swap coils with and see if their or your car acts differently. just remember your motor needs air, fuel, an spark to run. just try and work out all the possibilities of those 3

92 civic ex 4dr

Bad/worn out valve guides usually mean bad/worn out valve stem seals. That means lots of burning oil. It's doubtful that the valve guides are bad but you could need a fuel filter and to clean out the fuel rail and injectors.


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aavtec

Thanks for the replies ill pull the codes. Also the dizzy, wiring, fuel ect was all used when i was running the B18c1 and this problem was not present.

aavtec

Pulled the codes just now, the ecu is a stock p28 A/T. CEL codes are 7-TPS, 19-AT solenoid, and 41- primary O2. I dont have any o2 hooked up so ignore 41 and obviously 19 for A/T. But 7 for TPS is still unaccounted for, any help?

Deksinjo

41 is just heater circuit of O2 sensor ...

Your problem is 7 TPS, check wiring, short or open, connect at TPS wire voltmeter and measure voltage should be from 0,5V at ideli to 4,5V full throttle, reading must be smooth and constant, with out jumps or drops.

aavtec

Thanks for the advice, will probably diagnose the TPS code on monday. Could that be the cause of my problem??

Deksinjo

Yes, maybe on some point lose contact or give ECU wrong resistance, and you have reach or lean mixture.

aavtec

It only does it after 5500k, I have unplugged the vtec and still the same. Like I said the ecu is a untuned P28 A/T, any problems with the AFR when running it with a B16?

Deksinjo

I don't know what is stock ECU for B16A , but if is work for now with your engine there is not obvious reason why will not work more, only if you have some mechanical-electrical malfunction.
Cel say error 7 what means TPS malfunction, so check TPS.

Don't disconnect VTEC valve ! You will got more cel light and will confuse ECU.

Deksinjo

Will not work !
Read>>> https://honda-tech.com/forums/acura-integra-6/will-d-series-ecu-such-p28-work-b-series-b16-b18-vtec-etc-2318884/

aavtec

WRONG, actually it does work I'm running a stock p28 A/T ecu with a B16A right now but please keep in mind it's better actually i would say required to tune a ecu if your going to use it, but it's not chipped and I'm borrowing it . As for the problem that I'm trying to solve, it was present when I was using a OBD2 P72 ecu which I have strong belief is bad. Also I got horrible MPG with the P72, Just filled up full tank with the P28 and looks to be a whole lot better even WITHOUT a o2 present.
Now back to the tread, I will try diagnosing the TPS code once I get a chance sense I'm really trying to keep this motor as a spare, but with work and the B18C build it's kinda hard. Will post updates, but please feel free to post any thoughts or ideas as I often check posts.

grumblemarc

iTrader: (4)

You may be running one, but it's still the wrong ECU all the way around. You're running a SOHC ECU on a DOHC engine. You're probably running pretty lean at this point. Just a guess.

aavtec

Yes the maps are different, but as I've already mentioned a tune is required. Still you can run a P28 on a b series and with a proper tune you should be golden.

grumblemarc

iTrader: (4)

A proper tune which you don't have. So it's not running properly as you keep stating because the fuel maps are all wrong. Just trying to clear this up for anyone stumbling across this in the future. Sure you can run it or any ECU for that matter but it's not right.

aavtec

Thanks for the reply but I never said its running properly. I understand the maps are different but as i mentioned the ecu isn't chipped and I don't own it so I can't get it chipped. However even with the stock d16 maps the car does run, the ideal is at about 1k (vs around 2k with the P72 which still had the wrong maps) and I don't have any detention. Also my MPG seems to be a lot better, and no I'm not trying to miss lead anyone thus why I said a tune is required. Now can we get back to why my car putters up to?

Bumpsteer

I had the same problem on mine. I replaced the distributor, plug wires, plugs, and the ecu before giving up and taking it to the mechanic. He hollowed out the cat and it works fine now.

grumblemarc

iTrader: (4)

Check the TPS already. Shouldn't take that long really.

I didn't say you were misleading anyone. I'm clarifying, not for YOU, but for anyone that comes across this thread and reads and infers something like "Better gas mileage with a P28?" exactly why that may be the case. For future generations, run the correct configuration for your car.

aavtec

Don't think the cat is the problem Since i'm running a test pipe lol. I'll probably diagnose the tps code tomorrow. For me the ecu did help my mpg since i was burning fuel like a v8 with the P72, but you are correct a stock P28 ecu won't help your mpg, but with a proper lean tune you could help your mpg. Now since we have gotten off topic anyone who's wondering the correct obd1 ecu for a B16 is a JDM P30