Hard to start my 2G GSX when engine is hot/warm...what could be causing the problem?

[m[ohio]]

I've been searching for a few hours now both here and on DSMTalk and have found no real solid answers on what is causing my hard start problem on my 2G. When it's cold out out the car will usually start right up on the first try, but when the car was run recently or when it's really warm outside it cranks like crazy and won't start for about 15-20 seconds of cranking. Then it catches and idles rough for about 10 seconds and after that runs PERFECT. No idle issues, no surging or hesistating when driving. I've got a datalogger and have checked for CEL's and so far none have popped up. Any suggestions? I was thinking the coolant temp sensor or wire but I checked and the connection looks good. Is there any way to test to see if it is in spec?
Thanks!

 

[Airpoppoff]

have you checked your plugs, wires???

matt

 

[m[ohio]]

yep. a fresh set of NGK's BPR7ES's gapped correctly were put in about a month ago and a new set of Magencor wires went in 5k ago. I also put in a new fuel filter and pcv valve when I put in the NGK plugs.

 

[LaserDad91]

When it's cold out out the car will usually start right up on the first try, but when the car was run recently or when it's really warm outside it cranks like crazy and won't start for about 15-20 seconds of cranking. Then it catches and idles rough for about 10 seconds and after that runs PERFECT. I was thinking the coolant temp sensor or wire but I checked and the connection looks good. Is there any way to test to see if it is in spec?

Hmmmmmmmmm, sounds like you have a rich fuel mixture at start when the temperature is warm, or car is warm. When it is cold, air is more dense (more air per unit area), and therefore the fuel will mix better with the extra air. But when it is warm, or car is warm, the same amount of fuel will require more air. So maybe your engine is not adjusting for these temp changes at start up! Not real expert with the “electronics” but could any of your mods, be over riding ECU inputs at start?

Not sure what would cause this, and do not want to lead you the wrong way. I know there are air flow sensors and air temp, coolant temp, etc. but not sure at all what to check first. Basically your temp sensors will have a different resistance at differant temps. A “factory” shop manual would help and show the specs.

Next time it is warm, and car is starting hard do this. After cranking and car not starting, stop and pull a spark plug. Check to see if it is wet. Tap it against the palm of your hand, and see if it leaves a wet spot. If so, your too rich. This will verify the above. If it not wet, then it something else. You might want to check all the plugs, maybe one cylinder has bad spark, loose wire, weak coil, etc.

Another ck. One way to get more fuel into the motor is to depress the accelerator. You might have done this already. This will allow more air into the engine, without extra fuel, at start up. DSM’s might be different, but most “flooded” engines can be cleared by flooring the accelertor. Anyway, this should make the car start easier, cause you are vaporizing the extra fuel, by adding more air. Just don’t leave it floored when it starts!!

Also, make sure there are no “hot spots” around your fuel lines, etc. that could be causing a vapor lock condition. This would be more the case when the car has been run, and is hot, not just from a warm day.

Hope this helps!!