1996 Sportage Hot Start Issues

Frizzle Fry · 07-19-2008, 08:33 PM

Hey guys, New member here. My girlfriend's 96 Sportage just started having hot start issues. It has 97000 miles on it. I checked out an OBDII scanner and it has no codes whatsoever. I watched the cam move under the oil cap while cranking; no timing belt issues. I replaced the crank positions sensor (based on another thread on this forum), still having a hard time starting when hot.

If I let it cool I can get it to start. It'll run rough for a few seconds and the exhaust smells wrong (maybe rich). But once I rev it it seems to idle pretty smooth. It drives fine/normal if I get it to start, but as soon as I shut it down it won't start again.

I have a new O2 sensor I'm going to put in now, but I'm not holding my breath on that.

Any suggestions?

Frizzle Fry · 07-20-2008, 01:50 AM

Well, I replaced the O2 sensor, both coils, and spark plugs (gapped to 0.040). No improvement

...and still no codes. What next? Cam Position Sensor? Idle Air Controller? I'm pretty stumped right now

Frizzle Fry · 07-20-2008, 06:43 PM

Maybe everyone else is as baffled as I am over this? No codes make it really difficult to diagnose. It can't be fuel delivery related because when it does start it runs well. What else could cause it to have a hard time starting when warm? I have a PCV valve to put in but again, I'm not holding my breath... Other sensors? CPS, or maybe the IAC??? Could a computer fail in this way and give no codes? Help

Chicago · 07-21-2008, 11:22 AM

Have you tried holding the gas pedal to the floor while hot starting? It sounds like something is tricking the computer into thinking the engine is cold when it's hot and sending too much fuel at start-up. Then once the engine is running, the mixture evens out. That said, I can't begin to think what would cause that.

Frizzle Fry · 07-21-2008, 11:49 AM

Thanks for the response. Yes, I have tried that with no luck.

I pulled the two relays last night (fuel pump and main) and tested them; they're both good. Then with the ing sw in the on position I replaced them listening for the "click." The main clicked and the IAC started humming (normal as far as I know), but when I plugged the fuel relay in; no click. So I checked the voltage at the energize contacts and found 3v. One side to ground was 12 and the other to ground had 8.xx.

So I think I'm on the right track, but here's a twist. I jumpered past the relay and the fuel pump kicked on, but it still wouldn't start. So that 8v I'm seeing must be causing some other issues. I got the schematics from the tech site and will be tracing out the wires today. If any of this sounds familiar or you have any suggestions please chime in.

Also, just to add to the detail: It now seems to be doing this intermittently, not just when hot. I drove it yesterday with no issues and when I got home I shut it down and immediately restarted it without issue. 2hrs later it wouldn't start... So a short seems to fit the bill.