S2kichang

Hi s2ki
I have an ap1 that misfire at idle when the engine is hot. Here are thing I done already
1. 2 valves adjustments to 0.010 on intake and 0.011 on exhaust
2. replace map
3. replace idle air control valve and clean oem
4. Replace to ngk about 50k miles ago
5. replace primary 02 sensors denso
6. Professionally clean fuel injectors
7. replace idler pulley oem
8. compression test starting from 1st cylinder 232, 235, 237, 220
9. Head gasket test
10. Replace ignition coils denso
11. Replace ignition and fuel plastic connectors
12. replace fuel pump oem
13. cigar vacuum leak test

Still gives those intermittent misfire and idle rough. Cel only comes on on hot idle. Notice coolant smell when hot. No initial coolant leak. Short term fuel trim is -0.8 to -10% and long term fuel trim is -0.8%

please help

Slowcrash_101

Sounds fuel related, may be a pump or fuel pressure regulator issue. You replaced the pump, so I'm leaning towards FPR. Sometimes injector cleaning won't work if the injector is too far varnished. Is there any telltale signs on the spark plugs that a cylinder is running Richie rich?

Is the coolant system working properly? You have pressure in the system, heater consistently blows hot air once up to temperature? If the heat gets cooler when you're not moving you likely have air in the system. Fun fact our water pumps have a weep hole where coolant will always weep from. It has to in order to lubricate the external bearing and seal on the pump.

Chuck S

P02 and P03 are cylinders 2 and 3 respectively. Swap the coils out with cylinders 1 and 4 and see if the codes follow the coils.

-- Chuck

fernando.

I had a random misfire issue on my old AP1 which ended up being poor pin fit drag on Cyl #1 injector. I could duplicate it by slowly wiggling the connector and the engine would start to miss. I ended up depinning it and installing new pins. I too racked my head doing the valve adjustment 2 times over, replacing parts, etc.

Inspect all the pins in the connectors for the coilpacks and injectors.

Hashim289

Did you ever figure out what it was? I'm having almost exactly the same issues, coolant smell and all.

Slowcrash_101

How is your radiator fans working? Are they both pumping out a similar amount of air? One of your cooling fans could be lazy and not pushing as much air as a properly working one.