Hi all,

Cross posting from another forum to get some additional eyes on this. I'm having a strange issue where my CSI circuit gear is all functioning properly (time switch is new OEM, verified CSI sprays fuel on cold starts, AFM/TPS/IACV/CSI Ohm out per FSM specifications), yet after sitting overnight, I get a delayed start when the CSI is plugged in. Temperatures when I try this are around 70 degrees and the truck has been sitting for 8 to 10 hours so completely cooled down. When I unplug the CSI electrical connector and start it, it starts instantly with no hesitation. I'm struggling to understand what could be causing it to start better without the aid of the CSI fuel and I'm looking for suggestions. Someone suggested there could be another source of excess fuel but when I say it starts instantly, it's the flick of a wrist and it starts (maybe 1/8th of a second). There's not really enough time for the main injectors to leak in too much fuel to cause a flooding condition when the CSI sprays its fuel, and the injectors are freshly rebuilt as well. Is it possible the CSI is slowly leaking fuel overnight thus the vapors are there enough to not need the extra fuel triggered by the cold start switch? I would think if I'm dropping that much fuel in over an 8+ hour period, it still woudln't start as instantaneously as it does since the pressure in the system would be lost with a leak after an hour or so.

Things I haven't replaced:
- Fuel pressure regulator
- Fuel pressure damper
- Fuel pump
- Cold start injector

I haven't been able to find any answers to this, since most problems are that the CSI system is not working and that is causing hard cold starts. In my case, the purpose of the CSI system is detrimental to starting even though it's functioning properly and providing fuel.

Any thoughts here on what I could check outside of the CSI leaking?

 

Wild, just found out the same thing for myself this morning. 86 4runner, 22re rebuilt (unknown when). Always starts, tuned it up and idles smooth, but when starting cold it likes to crank for a few seconds. Again, it always starts, but being in Alaska, I want to figure this out before it gets cold. Grabbed some sensors from a junkyard (prayer, i know) and started troubleshooting. First, unplugged the CSI and started it cold this morning, turned over instantly. Curious. This made me assume it would be the thermo time switch being faulty, but seeing as you got a new OEM one and still have this issue, I'm suspecting I would too. Did you end up figuring anything out?

 

Is your IACV working, and do you have a cold idle and a warm idle? If your IACV is working it should be open at cold start to allow more air in...perhaps if it is broken it is closing off the extra air, and by not having that extra air, the extra fuel from CSI is flooding it?

 

as far as I know it's functioning properly. I have strong cold and hot idles. I was getting hiccups when idling hot, where it sounded like it wanted to stall for a split second but then kept idling. this was basically eradicated after new plugs, wires, coil, and air filter. now it's just that long cold start crank.

how can i test iacv? i read something somewhere about duct taping a hole near it temporarily to test it

 

sidenote; Timmy Toolman's 22re cold start troubleshooting video ends up leading him to the coolant temperature sensor being the actual culprit.