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Honda Civic EP2 K20A2 swap. Idle problem

2293 Views 15 Replies 6 Participants Last post by  nomdatyper
Having a serious issue getting my k swap running. Went over everything looked at so many forums and videos. The issue I'm having is it takes a lot of cranking but eventually starts rpm jumps to 3,000 drops to 500 rpm runs rough then stalls even if I apply any throttle it causes it to stall. I've replaced both lamda sensors NGK pre cat and Bosch post cat (not cheap sensors), both cam position sensors, crank position sensor, spark plugs are fine replaced recently when it was in my Type R (when it was running perfectly fine), Throttle body has a geniune TPS Sensor just replaced, IACV is new, EVAP is new, reapplied the gasket with RTV in case the thermal gasket was an issue, coils are fine checked them all for spark even if that was an issue it would just misfire, knock sensor is new, all the gaskets have been replaced before the engine was swapped in everything torqued to spec. Grounds are new and wire brushed the contacts on the valve cover to strut tower, ground from intake manifold to radiator support, ground from gearbox to chassis, moved the ground for injectors to the side of the head instead of the manifold as it's recommended by Hondata. Timing chain and tensioner is new and timed up right, lightened flywheel and clutch. Recently just bought a K Pro so now I have full control tried to disable to EVAP, IACV, calibrate the TPS (only showing -5 min and 40% max which is weird might be adding to the issue). The calibration I am using is the factory calibrated European EP3 which is where the engine is from, made sure it was running in Narrowband mode. Fuel pump primes, tried switching over the fuel pressure reg inside the tank, the fuel strainer and filter is brand new also. Engine bay harness, engine bay fuse box, dash fuse box and the whole harness was swapped out of the Type R also to make sure non of the wiring can cause any issues. Immobiliser, keyless lock etc all swapped over too even although it doesn't matter now that I have a K Pro. Started this swap on the 16th of August had it done by the 22nd only been able to drive it once about 200 ft before it stalled and wouldn't start again at this point all it had was the K Tuned conversion harness which ended up having issues with reading the lamda hence why I've swapped over the whole dash harness from the Type R.

Injectors were showing 10 ms and flashing red in the data log display in hondata, don't think that's normal maybe it's because of cold start ? I'm not entirely sure but I did change the gaskets for the injectors gave them a blast with brake cleaner to make sure they weren't clogged.

Last resort would be to check the timing which I'm 99% sure it isn't because its a brand new chain, guides and tensioner from Honda. Cams were lined up perfectly with the timing pins in the back to stop them turning, crank timing mark was lined up exact.

If anyone knows what I should try please let me know this problem is getting to me and nobody local will even touch it, qualified mechanic or auto electrician. A tuner was meant to show up one day but didn't show and ignores me, non of my car friends are willing to come out and look at it just suggestions for things I've already tried.
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I've skimmed it. Your TPS is no proper signal. Seems it is dead. The MAP sensor signal makes no sense, it shows in idle speed around 80 kPa (which is WOT area). The ECU does it job and enriches the mixture according the WOT correction tables and corrects that mass of fuel every 0.5 seconds. This overfuels your engine, makes idle running rough and so on. Check your harness and the sensors. Eventually change these two sensors.
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