Halfpricerice

Ok so after a month of googling and surfing all the forums and throwing somewhere around a thousand dollars at this stupid car, it still misfires at low rpm and at idle, but if I punch the throttle it runs smooth.
the car is a b20b swapped ek I have replaced what the honda peeps seem to call the "dizzy", spark plugs, spark wires, checked all grounds throughout the entire car, replaced the tps, the map sensor, fuel filter, good compression, changed the head gasket, replaced the o2 sensor, replaced the iac, adjusted the valves like 10 times because why not I'm despereat and it's running lean.... spark plugs turn white...p28 ECU with sst chip(unknown tune) oh and also replaced the timing belt and tensioner and yes I have e made for absolute sure the timing is absolute perfection with the cams and ignition.

JRCivic1

The P28 with the SST chip (unknown tune) is likely your problem. Get the car to a dyno and see how your "unknown tune" performs during idle, part throttle and full throttle. If it isn't perfect... TUNE IT !!!

motoxxxman

Yup I'm going with the "tune" too. Get a professional tune and you should be all set

Halfpricerice

Thank you both for the quick response.... can a tune suddenly go bad like that ??

Caoboy

I'm assuming you bought somebody else's project.

You can get by on an OBD2 P75 ecu, it's factory, it plugs in, it will run it. You can also find a factory CRV ecu, and it will be the correct ecu for your motor, the fuel trims will be perfect at that point.

Downsides: If you need to pass a state Referee, you'd most likely need the P75 and Ref it as a replacement Integra LS motor. Also, if you don't need to, and you just need that CRV ecu, they can be a little more pricey since it's less common of an ecu for sale. But, it'll be stock, it'll run right or you can at least rule out the ecu and continue on your quest.

Halfpricerice

Will the stock crv ECU not freak out with shift solenoids aren't they auto ? Also this is one of those obd0 to obd1 conversions which I couldn't pass the inspection anyways because the scanner wouldn't connect lol and yes this is someone's project we bought for 800 bucks from some buy here pay here place. So should I just go to a pick and pull and snag the ECU from the crv they have ? Also keep in mind the car ran fine for quite a while like 4 or 5 months

Caoboy

The only reason somebody converted to obd1 is to run a p28. It's not necessary on a stock b20 unless you're heavily modded and i'm assuming that's not the case.

Caoboy

Are you in California?

You can pass a B20 through Referee if you run it as a replacement motor for a b18 swap.

Halfpricerice

I live in Texas and no it's just a stock b20b. Just got done at the pic and pull to no avail, all the crv's and integras have all been torn apart already. As soon as I get another ECU I will post an update. Big thanks for all the help so far... I am also on a cobra forum and a Corvette forum and yall have already been way more of a help than both of those forums combined.

JRCivic1

Maybe, but unlikely. It is possible that the ECU has been damaged... OBD-1 ECU's are getting old and a leaking cap can cause all sorts of issues.

You didn't mention that in your initial post. We cannot rule the bad ECU out at this point, however, it may be O2/Closed Loop related, so I suggest you get the car to a tuner and see if you can get the Closed Loop operation turned off and see if the engine performs like normal during idle and part throttle as well as full throttle.

DCFIVER

Misfiring at idle or low RPMs is almost always a valve sealing/valve train issue. Usually a dynamic compression test will reveal nothing.

However, a simple relative compression test will reveal the problem cylinder in 10-15 mins,provided you have the tools and know-how.

I suggest Goggling or Yelping a professional repair facility in your area.....