I have b18c5 with p72, 370cc injectors (problem also existed with stock 240cc injectors), f.p.r., I/H/E.

Lets say I start the car in the morning, drive it around for some time, then let is stand for couple hours. When I try to start it back up again, it will have rough/low idle and I can smell a little fuel, it will continue like that for 10-40 seconds and turn into normal idle. If I try to start it with gas pedal slightly pressed in, it will start and idle fine (btw.. what kind of damage can pressing gas pedal do?)

Does anyone know what causes this problem and how to resolve it?
Thanks in advance

 

you need to either remove fuel at startup, or lean out your fuel map there. No harm in pressing the throttle.

 

tried to lean out/adjust fuel maps, the car is well tuned. but it still happens, worse in hot weather. what else could be the cause?

 

update on the problem..

Although i'm not completely sure if its gone, its definately got better. Weather is cooler now, it used to get worse in hot weather, i'm not 100% sure it been solved.

When i turn the key, I don't start the car right-away, I wait for fuel pump noise to stop then check engine light goes of, then I start the car. The car starts all the time now and I haven't any rough idle lately.

The technical side of it, i'm not too sure, but I think with obd1 computers, as injectors get heat soaked, there isn't enough fuel at the startup, unless you do as above and wait for fuel lines to open. when starting earlier as you would with obd2d - rough/low idle might happen.

It makes sence now cause the car was well tuned and runs great once warmed up.

 

My car has the same problem. OBD1 P72 running 440cc injectors with Techtom engine management. It started fine for 2 years with the same setup and then this started. I still haven't figured it out. Same thing it is worse in hot weather and fine in colder weather especially if it has been sitting for a while. It is also hard to start in really cold weather, but I'm talking below 0 farenheit.
So far I have tried plugs, wires, air filter, fuel filter, I ran an MSD with external coil for awhile, injector cleaner, PCV valve, and I cleaned out the throttle body and IACV valve with throttle body cleaner. I am about to try the ignitor, but I doubt that is the problem. I will let you know. If you figure the problem out, feel free to IM me.

 

Hmm, I don't have a hondata, but my car starts the same. I think the problem lies within the coolant temp and the maps of the fuel on the ECU. When the car sits for a couple hours when it cools off slightly, the temp guage thinks it back in Cold Idle mode, thus injecting more fuel, just like in the morning. But I backed my fuel pressure off a bit, and the car starts a bit better but still has issues when its hot out. When its cool, it runs and starts perfect.

 

Oh yeah, thats another thing I tried. I put an adjustable regulator on and tried playing with pressures. I went down as low as I could (40psi) and it didn't help. My normal pressure is 48psi. It could be the ECT sensor I guess. I think I will try it after the ignitor.

 

I'm having the same problems with my car.

Starts fine in the morning, drive a few minutes, shut down. start again and it wants to die. stomp on the gas for a few secs and it goes away, or try to drive normally.

my friend had that problem but tuning solved it.

 

i think thats the problem, during winter time my car started fine at all times, today, with warmer temperatures it started to do the same.