Car Tough To Start When Warm..

[RioRed95Cobra]

Yeah, i've read everything I can on this subject for a couple of days now..

Car starts great when it's cold.. crank crank crank fire.. perfect.

Drive up to store.. get gas. Try to do it again... crank crank crank crank crank.. nothing. I have to push the gas pedal almost all the way to the floor to get the car to fire.. and then it runs just fine.

Only downside to this is that if I don't pay attention, like yesterday.. I put in a new set of plugs.. 4 times driving around town I tried to just normal start while warm.. nothing. After having to try 2 and 3 times to get the car to fire, it did.. but eventually the car started hesitating bad.. yanked plugs and 6/8 of them were completely black, toasted with fuel.. 1 day lol. Last set of plugs went 2 months and looked pretty good.

Any ideas? Adjusting the air screw on my TB help at all? I am not 100% where that dumb screw should be set tbh.. car runs amazing though, lol.

Thanks.

 

[imp]

Yeah, i've read everything I can on this subject for a couple of days now..

Car starts great when it's cold.. crank crank crank fire.. perfect.

Drive up to store.. get gas. Try to do it again... crank crank crank crank crank.. nothing. I have to push the gas pedal almost all the way to the floor to get the car to fire.. and then it runs just fine.

Only downside to this is that if I don't pay attention, like yesterday.. I put in a new set of plugs.. 4 times driving around town I tried to just normal start while warm.. nothing. After having to try 2 and 3 times to get the car to fire, it did.. but eventually the car started hesitating bad.. yanked plugs and 6/8 of them were completely black, toasted with fuel.. 1 day lol. Last set of plugs went 2 months and looked pretty good.

Any ideas? Adjusting the air screw on my TB help at all? I am not 100% where that dumb screw should be set tbh.. car runs amazing though, lol.

Thanks.

It sounds like your Engine Coolant Temperature Sensor may be on the fritz. If it is inoperative, the engine will continue to run fuel trim in "open loop", which uses extra fuel intended for a cold engine. This would explain hot starting: getting too much fuel. The sensor is very easy to replace, if you don't want to try testing it's output. Not expensive. imp

 

[Noobz347]

Pull codes

 

[RioRed95Cobra]

Yeah I pulled codes lol.. 563 ccrm is only thing that comes up.

Doubt that has anything to do with it.. or.... could it? I just built this thing from scratch, took 8 months using 2 cars.

Can has run fantastic after s-trim and all the other bs that went on.. just this one little issue. Car is running a quarterhorse with a tune from Willie out at DirtyRacing in Virginia (good guy, look him up if you need mail order tunes, because he is goood), and have played a bit with the binary editor but cannot get this sorted.

The ECT sensor was a pull off a junk yard car, lol.. but for 2 bucks I had to try, haha. Guess it's a run to the auto parts store.. I will go try the resistance on the pins and see if it's the ect.. but i'm guessing it is.

Also... what else would the ccrm affect, if anything - if that's what's doing this? Because the car runs awesome.

Thanks guys.

 

[imp]

@RioRed95Cobra
CCRM is nothing more than a couple of relays incorporated into one box, instead of individually as earlier. 2 Fan relays, PCM Power relay, and Fuel Pump relay. Looks like this:

 

[Bad69cat]

Could be the fuel pump relay - might do a pressure check on it when it's hot. Also I had a jeep one time that acted like that and the crank sensor died out of the blue....... maybe they die a slow death?

 

[jozsefsz]

In your tune - the cranking fuel pulse-width is suspect. If your injectors are >24lb that value needs to be brought down accordingly or you'll have hard starts when hot due to too much fuel. Holding the accelerator all the way down causes the injectors not to fire at all (it's the engine-flood clearing mode of the computer which mimics how it was done on carbed cars). I'd be surprised if a professional tune missed that, but it might be worth comparing your table values against the stock values. You might also have some mechanical failure causing the rich condition, but I'd definitely check to see that those values were adjusted in the tune.

 

[RioRed95Cobra]

Interesting.. thanks Jozsefsz! I'll bring it up with him!

 

[Christian Cornwell]

Sounds to me like your timing might be locked out and set too low. Have you checked the spout connector to see if it looks okay? If it looks suspect, try cleaning the contacts in there and put in a little die electric grease. All the spout does is complete the circuit to the computer to let it adjust timing if you think the spout itself is bad stick a paperclip in there temporarily. I would diagnose with a timing gun. Take and pull your spout and fire the car up and using the timing gun find what the timing is set at. Ford says 8° most guys like to bump that up, read around on that if you feel like you wanna bump it up. After you find out what your car is set at put the spout connector back in and check timing again. Should read higher than it did before if the computer is making changes.

Easy place to start if nothing else.