Hi there,
I was working in the area of the distributor and mistakenly touched the connector to the ECT sensor. When I tried to reconnect the plug I noticed the plug was broken and tried to get it to stay and the plastic housing broke. So I took the housing off and now I just have 2 wires. I tested them and I get a reading between near +4 to not quite +5v reading and I get a -4 to not quite -5v reading on the other. I replaced the sensor since I originally was getting a P0118 code but when I put the new aftermarket sensor in I am now getting a P0117 code. Is it possible that I put the wires on wrong? Will something happen if I have them connected incorrectly? I also wanted to mention that ever since the connector came off I have a high idle.

All of this started because I felt my car was going through too much coolant with no visible leaks anywhere.

Any help would be very welcomed. Thanks in advance.

 

I think the ECT sensor is just a variable-resistor, so it shouldn't matter if you reverse the wires.

 

Hi Jim,
Thanks for your input. I really appreciate it. I wanted to also let you know that I was getting screwy readings on my multimeter because one of the wires was not making good contact. I cut the wire and put some female disconnects on there. I measured 5 volt on the red/white wire and checked continuity on the ground wire and all was good. The check engine light went off after installing wires on the ECT sensor but I had to disconnect the negative off the battery for 10 minutes or so to erase the code that may have been saved in the ECU because I was having long crank time which I read somewhere else is a symptom of P0117 code. Thanks and hope this does it and can be repair free for a while.

 

Disconnecting the battery would have cleared the codes. But if the problem is still there, the error would come back pretty quickly. Hope it's fixed!

Bad connections are frustrating. I drove myself nuts one time and it turned out to be a wire had become frayed and was making poor contact with itself - inside the insulation in the middle of the wire!

 

Hi Jim,
I have a frustrating problem that I just dont know where to look.
After taking care of the P0117 and P0118 problem there is a lingering extended crank time that only happens when the car is cold or has had time to cool down. The car was running fine up until I got the ECT problem. Prior to this I was having a hard start problem that I ended up taking care of by replacing the fuel pump. Now I have this hard start problem but only when cold. Once I start the car the first time I can turn the car on off and infinite amount of times and no problem at all. The car runs fine and I have no CEL. I have changed plugs, wire,cap and rotor also fuel pressure regulator,main relay.
Any help on where to look next would be appreciated.

 

Just to check whether this has anything to do with fuel pressure...

When you first turn the key to "ON" but don't immediately turn it to "START", the fuel pump should run for 2 seconds then quit.

So... try this to see whether it helps the problem:
- key to ON so the pump is running
- key to START before the 2-seconds is up, so the pump hasn't stopped it's priming cycle.

I'm wondering if the fuel pressure bleeds down too quickly. If so, then maybe the FPR leaks forwards, or something like that. I think if the engine is all cold, then the coolant-temperature-measurement will trigger fuel-enrichment.

An alternate (better) test would be if you have a fuel-pressure gauge. Have the gauge connected, run the engine, and watch how fast the pressure drops off after you turn off the engine. The shop manual has some kind of specification for that.

 

Hi Jim,

I tried your suggestion tonight while running errands and both times the car started right up the way it should but on my way back I got a check engine light that came on. I will scan it in the morning and see what code I get. Thanks for your input. I will report back tomorrow.

 

Jim,
I went and got the code read. It came up as a P0420, not sure if its related to the problem I am having or not. Let me know what you think. Thanks a million for all your help.

 

P0420 is "catalyst low efficiency" which I don't know whether that might be related or not. If something is still flaky with engine-temperature measurement, then it might go from running rich to lean, and not real well-controlled fuel mixture. That's hard on a catalyst, and/or it might simply be the 2nd O2 sensor picking up the effects of rich mixture.

How old are the oxygen sensors? They can probably get sluggish for awhile before they eventually trigger codes P0131, 132, 133.

Another thought, but I'm not real sure about this... Is your engine a ULEV engine? If so, what I don't know is whether the ECT sensor is "special" for the ULEV engine. The front O2 sensor certainly IS special for the ULEV engine.

 

Jim,
As a test I reset the CEL by pulling the 7.5amp fuse on the passenger side.
I started the car the way its meant to be started after the 2 seconds of fuel priming and once again I had the same condition of long/ hard start. I drove maybe 15-20 miles and no CEL. I am thinking that maybe the P0420 code had something to do with starting the car the way you recommended about not waiting the full 2 seconds before starting.

PS: The engine is a VTEC. Ill let you know if the CEL light comes back on.