i bought 90 zc crx.it had a vtech engine(sir i think) in it with other owner.it was replaced with zc.so i have it.ive put a D16A9 engine into it with L3 gearbox.i have to change front engine mount as it wont sit right. the L.E.D picked up a few problems but we sorted them.there are no faults now.But the engine isnt running right.its over fuelling and running rich through all revs.
Now, with the old zc the cat light was flickering.(i didnt think a zc had a cat,was it the one left in it from the sir engine??)i have it in the garage, they reckon to put a cat on it would solve my problem?any ideas?are there any wiring mods to be done with this swap?i thought it was meant to be a straight swap?thanks everyone

 

huh?

 

waht was your question

 

sorry, my question was, would putting a cat on the engine solve my overfuelling problem? as i thought it was a straight swap with the 2 engines?theres a cat sensor in the car that was in it with the zc engine!i thought zc didnt run with a cat?could the cat have been belonged to the sir engine that was in it?if so how did the zc run perfect with it?the cat light in the dash flickers sometimes,even with the old zc engine, would this be upsetting the new D16A9 engine running.Maybe looking for a cat when there isnt meant to be one??and causing it to run incorrectly?
im 4 months trying to solve this problem.so please be patient with me as im only learning as i go along thanks to all you guys and ive learnt a great deal

 

edit

 

Well, I'm 100% positive the D16A9 did not had a catalytic converter. But isn't the ZC exactly the same thing as the D16A9 (like the ZC is the JDM version of the A9, and viceversa)?

As for your problem, I don't know...have you tried to get a cat and install it? If it resolves the problem, them...well, good for you.

It if doesn't, them I doesn't know what it could be. Maybe someone else could help you. Good luck.

 

Where are you located?
Not everybody here knows in details about d16a9 complectation.

Which ECU is in the car right now? (which engine it's intended for, and what is the ECU code?).

If the ECU thinks you still have a vtec motor in the car, it may be giving it more fuel than needed.
Another thing - if you have a check engine light, ECU gets into an "open loop" mode - it doesn't pay attention to half the sensors and dumps a lot of fuel into the engine just to be safe.

I never thought of a cat. converter as a part of an engine, rather a part of exhaust system. I guess if the ECU is looking for a cat converter sensor (? wow, never heard of such), you better have the cat there. And if ECU does not expect any cat to be there, then don't put it on.

 

the original zc ecu is in it.i will check the ecu code itself tomorrow.it shoul be ok fot the D16A9 engine shouldnt it? i must check code anyway
im located in Ireland! if its in open loop mode,how do we get it out of that?
weve reset it by taking the fuse out under the bonnet.
sorry i meant the cat as part of the exhaust system not engine.

 

personally, I would check that all the wiring is in a proper state, as the vtec would have required a few mods; if this gives you no joy I would then track down and install a proper D16A9 ecu. I would not assume that a ZC ecu is exactly the same as a D16A8/9 ecu. There seems to be many differences, small or otherwise, between parts/systems/engines etc. that are supposedly compatible. Figure that the JDM ZC is designed to run on fuel up to 100 octane and you will begin to get the picture.


good luck

P.S checking & cleaning all your grounds and going over your vaccuum hoses wouldn't be a bad idea either, as well as checking that your various sensors (especially the O2) are set properly and functioning correctly.