Here is some background on my car: 04 MT 62K and I bought it at 58K. I changed coils, spark plugs, wires, MT oil and differential oil at 60K, also cleaned MAF at 60K. The car is running great but here is the issue.

I usually start the car and wait 3 min in the car to let it warm up a little bit and then start driving at low RPMs until it is fully warm. When I start it, the RPM is usually at 2500 to 2800 and slowly dips down as it warms up, until it sets at around 800 when it is fully warm.

Yesterday morning when I started the car the RPM was at 2700 as usual, then it started going up and down rapidly to 1300 and back to 2700. It did that for 5 to 10 seconds then it went back to 2500 and started going down as it warms up as usual. In the evening going back from work did the same thing but jumped up and down only 800 RPMs and did it for 5 sec. While going home I warmed it up completely and drove it hard, no power loss and everything was fine, no MIL. Today morning I connected my scanner to monitor sensors data while it is happening but it happened only for 3 seconds and only thing I could check at that time was Fuel trims and they all appeared to be normal.

I am completely lost. Last thing I need to add is last couple of nights the temperature reached around 40. I hope it is not temperature issue cause the temperature reaches -20 in winter time and I know people drive this car in Canada so what can it be?

 

Heya Khaf.


A sensor, switch, or fuse keeps tickling the back of my head as the cause. I am trying hard to remember, but I think when I was splicing into the clutch interlock switch I spliced the wrong wire that ended up being an sensor/switch detecting clutch position for idle control?, and my idle started doing that. A wire running under the dash near the clutch switch.

I might be remember up the wrong tree here, I am not sure exactly what I am remembering.


I do remember seeing several videos of 8s doing that, but never dug into them to see why.

 

scroll down this section of the forum and read the thread that starts "Idle seek..."

 

Well thanks to both of you. It kinda make sense. On Sunday I used WD-40 on my clutch release spring since it was making squeaking noise. That issue is solved but now I created a new problem. I was very careful spraying and used rags to cover those switches but I might have got some in the switch. Now the question is how can I clean it? I am thinking of removing the switch if possible and use MAF cleaner since it is contact cleaner. Is it a good idea? BTW there are 2 switches there one behind the clutch and one in front of it, Which one we are talking about?

Also ZOOM44 what did you mean by "scroll down this section of the forum"? I did an advanced search on "Idle seek" and found one thread and read that. I really appreciate you trying to teach me how to fish but I don't know if you meant doing an advanced search?

 

Starting to be pieced together now

When I was messing with the wires, I messed with the wrong one of those two. I THINK it's the one in front of it, that is pushed in when you don't have your foot on the clutch. You likely interfered with the electrical connection within the switch, and cleaning it is all that is needed.


And the best way for searching the site is to search using Google.com, and within the search box type site:rx8club.com

Their search engine is far superior to ours.

 

RIWWP, I completely agree with searching but my problem was I did not know what keyword I should use for my problem.

Now back to problem should I wipe the switch? open the switch and clean inside? Try spraying MAF cleaner inside the switch without tearing it apart?

I don't want my next question be what is the part number for clutch switch and how I can start my car until my switch arrives.

 

If you can find the actual electrical contact point, that's what needs to be cleaned probably. Taking a guess here. I don't think WD40 is a good electrical conductor, and that contact is probably the most exposed piece that can get interfered with.

It shouldn't be very difficult to pull off and put back on, probably just a bolt or clip holding it in place and an electrical connector to the wiring harness, but honestly I haven't done it.

The switch that messes with the idle isn't the clutch interlock switch that you need to start the car.

 

RIWWP you are the man. When I came home I checked it and touched the switch and sure it was oily. I somehow managed to get WD-40 on that switch. It is the one closer to driver seat same as what you said. It was dark tonight when I came home to try and remove it. I probably remove it tomorrow night or this weekend and clean it.

Thanks again.

 

i meant go out of this thread into the trouble shooting sectiob it is in where you can read the titles of the other threads. then look at the other threads and find the one that starts "idle seek"

as im typing this reply it is above your thread



read that thread. because that thread is discussing a similar complaint with the same root cause.

https://www.rx8club.com/series-i-trouble-shooting-95/idle-seek-only-when-gear-clutch-193779/


sometimes its not about using the search function, just looking at other current threads. sometimes even going to page 2 or 3.