DC4 CEL code 6 - engine coolant temperature, idle problems + not starting

[dazza]

Hi all,

Had my GSi (2000, auto) for almost a year now and it gave me nothing but trouble. I know I am the one to blame that I rushed the purchase and didn't go over the car carefully.

The story is pretty long but I am not sure if all these problems are linked somehow, maybe not, but that's why I'm here to find out.

Earlier this year in Jan/Feb my car's transmission cooler line bursted on the side of the road. Had it towed to mechanic and they changed a new hose and topped up with genuine Honda ATF. Note that before this incident, the car had no CELs or any abnormal operations, at all. Now after the hose change, I noticed the temp gauge sometimes go from 40% to 60% and back. There are no warning lights and I check my coolant regularly and there are no leaks. The range is quite small so I didn't pay much attention.

Until last week: after driving my car for 5 minutes after a cold start, CEL will turn on, and the RPM with the car stopped in Drive is about 1100, and when in Neutral or Park it fluctuates from 1100 to 1500 and it just keeps on doing that. If I put it in D and don't press any pedals, the car will auto accelerate up to 20k/hr and it will actually shift to 2nd gear without any input. I didn't let it go any further after that but you get the picture. I pulled the diagnostic codes by jumping the 2 connectors under dash, got 6 short flashes which means ECT (engine coolant temp). Now for the past week, interestingly there are 2 times in which this RPM and CEL issue did not occur. I do not know why, as I use the car to and from work only and I drive the exact same style.

Just earlier today when I went to the shops and parked my car, and then I came back approx 15 min later and tried starting the car, the car will turn over but not start. I called roadside assist and they came in 30 min, and magically the car started fine. The guy told me maybe the engine is flooded (with fuel). After that he said it should be fine but get it checked soon.

That's it for the story, I cannot understand what might be causing the issue. If I were to take a guess, maybe when the mechanics replaced the trans cooler lines, air got into the radiator? From what I learnt, air in the radiator could cause improper ECT readings. Then I assume the sensor thinks the temp is too LOW, so it revs the engine higher to warm it up? But the engine is ACTUALLY HOT so the pressure bursted the trans cooler line? And the fuel flooding might be because the engine wants to increase RPM so it injects more fuel and to cause flooding? But I can't explain the revving up and down (fluctuation) when in Park or Neutral. I am just assuming everything here so, that's why I need your guys help with this.

I am taking the car to mechanic later this week but maybe I can learn more about the problem here? Thanks in advance for replies!

[ECU-MAN]

You need to test the ECT

http://www.ozhonda.com/forum/showthr...ics-Code-6-ECT

Expect the engine to run rough when the MIL comes on as the ECU will richen the fuel mixture when in limp mode to protect the engine.