cold start hesitation

i have a redtop sr in an 89 coupe, stock setup aside from a fmic. i just changed the plugs and o2 and fixed all boost leaks. when i start the car it idles fine, i dont actually know cause i dont have a tach but it sounds normal. if i try to rev it up it sputters for the first 1/4 of throttle then it revs up fine. im thinking its fuel related. sounds like the engine is flooding. i checked the resistance of my injectors, all good (11-12 ohms). when the engine is warm it runs fine. i also came to realize that the fuel pump is always running when the key is on. could this have ruined my fpr. i could use some help guys. thanks in advance.

corey

could also be plug related i had an issue with my rb20 motors hard starting due to using a cold plug but ran perfect when it was warm

I would check the readings (with a voltmeter) of your coolant temprature sensor. Check it when its cold, then again when its hot. If you have a FSM compare your readings to the specs. Im not going to go into detail but there is alot that can be traced down to a bad temp sensor, your symptoms included.

I had a hesitation around 1700-1900 rpm when I first got my 240. It was on a stock KA24DE though. I had the fuel filter replaced, and its been completely gone since then. Also, one of my injectors was slowly dying, and eventually it ohmed out to like 35ohms, so I changed that out too.

Since you have a multimeter, try testing your TPS (throttle position sensor) and the coolant temperature sensor; it should say in the FSM how to do it and it should also have the corresponding voltage values for properly functioning sensors.

My best description of that hesitation was on very little throttle trying to hold the rpm’s steady at 1800rpm, and feeling like you’re hitting a slow rev limiter. lol

i changed my plugs to some bkr7 and it seems to have helped the problem but not fully.ill try testing the ECT and TPS. thanks guys