rough idle, code 41, possible miss

[cbfomoco]

I have installed 91 mustang efi on my stock 302. I got exhaust put on last week and this was the first time the unit was on the road in about 25 years. Any way I am trying to fight out the last gremlins.
Here are my specs:
Motor is an old firing order 302 from a 79 t bird.
upper and lower intakes are explore gt40 and explorer throttle body.
stock orange 19 lb injectors ( used not knowing condition)
stock a9l computer that efi guy fixed.
stock 91 reworked harness. ( tab and tad resistors) egr eliminator. is using a canister purge though with a charcoal canister and hooked to the intake ( vent on tank to canister to purge to intake)
Stock a1 cardone reman 91 mustang maf sensor
New: map sensor, temp sensor, stock fuel pressure regulator, bosch o2 sensors, in tank electric fuel pump, reman cardone dist with correct gear, new cap, rotor, plugs and wires 180 t stat ( I know it needs a 195 and have one just not put in yet.
I am not sure where timing is set as I can not see the pointer with the alternator on. I think I am in the ball park though and was set with spout connector removed.

I have running codes of:
31c
41c
koeo
84o
31 c
41c
(have not been able to get into cyl balance test and also shows as a 6 cyl on the tester)
My check engine light is on. Idle has been set and is in range. Idle is about 1000-1100. Some times check engine light will go off but comes right back on when the throttle goes above 2500 rpm

idle seems to hunt up and down some. and could have a miss at idle but is not really pronounced and does not seem to be above idle.

I replaced the fuel regulator this morning with an oem one( had and adjustable on it) with no change. I have a gauge in the rail and at idle I am about 32 psi but this does change some and have seen it go lower. I checked the vacc hose to the regulator and see no fuel. With the vac line unplugged and my finger over the line the fuel pressure will go up but motor does not seem to like it.

I took starting fluid and checked for vac leaks and no change.


What would cause the 41 code and what should I do to check it? 02's are both plugged in I think the 84 and 31 are not my issue and just no egr. I am leaning toward injectors but kind of a guess at this time.
I am open to testing and ideas. Thanks

 

[RustBeltRefugee]

It believe this is a sequential EFI system and possibly you are running a different firing order. I am not 100% sure but you might need to get the injector order to match your firing order.

Do you have the original flywheel, damper, cam on the 79 t-bird engine?

 

[cbfomoco]

I am using the original bronco fly wheel, damper was a new correct damper from summit 28 oz . I know that the motor was rebuilt at some point. It does have a small cam in it but I am not sure of specs and past owner is not around any more. With that said it is not a loopy cam and the motor ran well in the t bird with the carb on it.

Mine is firing order: 15426378 not the ho order of 13726548 Thanks

 

[RustBeltRefugee]

Injector order might cause rough idle but it does not appear to be too big of a deal.

http://classicbroncos.com/forums/showthread.php?t=249733

 

[Viperwolf1]

EGR codes will set the CEL so ignore that for now. Code 41 says lean on the passenger side. Make sure all the injectors are plugged in. You should be able to get cyl bal test by stabbing the throttle after the KOER codes flash.

 

[cbfomoco]

Thanks for the responses. I did not change the injector firing order to match the old firing order. I will double check that all the injectors are plugged in. I got to thinking some last night that i did not have this code until the exhaust was put on. I was laying under it yesterday with it running and notices that I do have a little bit of an exhaust leak where the head pipes meet the header flanges. I am going to fix that and check that the injectors are all plugged in and go from there. I will update when I get the leak fixed. Thanks

 

[cbfomoco]

I thought I would up date this in hopes that it might help someone else out. I fixed my exhaust leak and made no change. I pulled the pass side exhaust pipe off and found that my exhaust had worked its way up in the collector and crushed the oxygen sensor. I replaced the sensor and welded the pipe up. No leak and code 41 is gone. I have other issues now but will start another thread. Thanks