I am having the same problem in my crx b16a2. I unplugged. the primary o2 sensor and it still didn't work. When it was cold it will idle at 1000 rpm but when it hits 150 on the temp guage it revs up to 1.2 rpm, revs higher then dies down like its about to run out of gas and the idles back up to 1.2 rpm. I've tried the fuel injectors, fuel pump, all the plug sensors on the throttle body.

 

What ECU/Distributor are you using?
How good was the wiring job?
Any CEL?

 

pr3 with a new distributor
it has an HF wiring harness
i don't know what a cell is

 

C.E.L= Check Engine LIght.

 

sorry but no. no light codes come up.

 

My bad. no engine light comes on or no computer light codes.

 

Really hard to pin point the problem. Is your car an HF?

When trying to diagnose the problem you have to give plenty of background info.
- Was it running fine before?
- Did you make any changes?
- Why did you think unplugging the O2 sensor would fix the problem? That doesn't make sense. On the contrary, that would cause a Check engine light CEL. You need someone who knows about these cars that can take a look and see what the problem is, fixing over the internet is doubtful.

 

well we bought the car with another b16a motor in it and it was doing the same thing. we put in a b16a2 that is built for Turbo. we are also having problems with the vtec and the throttle control sensor .

 

You need to find a local guy who knows these cars. It could be 100 things.

 

Pr3 uses 2 02s do you have both hooked up and wired in?

 

have you tried changing/cleaning the Iacv or the Throttle body? also check for leaks around the intake manifold. May be a vaccum leak.

 

also can be this. ^^^^



https://honda-tech.com/honda-crx-ef-...stion-2999890/

 

The two o2s are all good. He has already checked and cleaned the iacv. He wants a 70mm throttle body. We will check the intake seal. thank you all for the help you are providing.

 

one thing a lot of people complain about when doing engine swaps is that
the engine, ecu and harness all have to match.

Some people try hacking at harnesses and it can get pretty dirty but if you think about it if you can separate the wiring required for the engine from the rest of the accessories.. and then you just transfer everything as it is in the donner car over to its new home then it has to work perfectly as it did before.

IDK its what i hear ... people try to get the ecu to use part of the original cars harness and part of either the doner or hacked in wires.. and it becomes a mess..

unfortunately you don't have a full doner you have what they did and what you did.. so you need to get a wiring diagram and verify everything that should be there based on that engine ... is there...

 

The wiring is all good. we put another motor harness on it today, it did better but it will still fluctuate when at operating temp. (150°f) but now it only flucts from 1rpm to the first notch above one. This is something very minor and is the only thing holding us back from putting the Turbo on. We have changed injectors, distributer, plugs, wires, map sensor, tps, throttle body, everything we can think it would be. The only thing we haven't changed is the iacv and that's because we were having the same problem with the b16a that was in the car body before. WTF!!!!!!!

 

Pics are gone but check this out:

https://honda-tech.com/honda-crx-ef-...-iacv-2153910/

 

Vacuum leak.

Nothing else produces that behavior.

 

FITV clean and adjust. With a turbo, you'll have tuning software to set target idle also. Though I'm not sure if that would compensate for a FITV that was out of adjustment.

 

Yeah this is my first thought.

 

the TB that we are using doesn't have a fitv. so its not that. both of the iacvs works cause we checked them. As for the vacuum leak, why wouldn't it fluct when we first crank it up, cause untilled it warms up it runs like a new motor. this is driving me insane.

 

Well this is bullsh!t. we took the iacv off, let all the little air bubbles out the radiator, put the iacv back on and now the motor has been running for twenty minutes at 150° like a brand new motor.

 

I been having the exact same damn issue! so annoying!!!!!!! im going to do this tonight and see if it helps, but just to make sure im doing this how you did how did you run the car without the fluid coming out where the iacv is??

 

You shouldn't have to remove it. Just bleed your coolant system.