Issues when hitting vtec (no YO!)

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autox19

Member
Without writing a book, here is the skinny. Jdm b16 stock with header. Bought 8 years ago ran sweet. Swapped into a fiat x19 and finally got it done last year. Spun bearing before I could run it into vtec. NOTE: if engine sits for 7 years, prelube like it was a new build. Replaced with other stock bottom end. (Used oem head gasket). Doesnt have the umph it did. Part of the reason is it sounds like it is missing once vtec engages. (Tune has it set at 5300 and I can hear it changing) New ngt plugs, new wires, but new ngt wires will be in tomorrow. Running crome with the tune it came with. Tried yesterday to use a base p30 tune and it was running lean even out of vtec (around 17-18) put original tune back in. I dont have a data logger. I am about to swap to Neptune (for a few reasons, data logging being one. )

Running out of things to check.

Odie
 
It had the same hp when it was in the honda and had umph. The fiat weighs less than the car it came out of so I would expect it to be at least the same. The bottom end was swapped with another stock bottom end. I looked at the pistons and they are both stock pr3. The tune stayed the same. With the same ECU. I dont have a stock jdm ecu to throw in there plus the dizzy is an odb1 (was on the donor car as well) and a custom rywire odb1 wiring harness (to keep the odb0 injectors and resistor box) which is what the donor wiring was like.
So if you want, take the umph out of the question and go with what would cause it to run rough in vtec.

Odie
 
No cel, oil pressure 75+. (Dont remember exactly but I know it is up there) timing 16 degrees advanced 750 rpm with check circuit grounded. I can hear a difference when I hit the rpm. A little louder but then it is missing. Not a consistent miss like one specific cylinder missing. More like stumbling.

Odie
 
Good question. I will have to check that. Wont have time today. I do know that it is smooth as silk before vtec. Hopefully it won't be raining tomorrow and I can shoot a video

Odie
 
Check compression, check screen on vtec solenoid , reset timing to tdc and check marks , use a known good STOCK MAP ecu
 
I checked TDC (long screw driver method) and it matches up to the lines on the pulley. will google how to check screen. as far as the stock map ecu, what stock mapping ecu would you recommend? the engine is b16a (odb0 injectors with resistor) but the dizzy and wiring are odb1. It will throw an eld code as I dont have an ELD.

odie
 
Think I found the issue! New ECU is going to be ordered. Went out to start it and no go. Looked at the ECU. IC14. Is shot.

Odie
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