Can't get my idle down on my S13

[Jim3798]

Hey guys I need some help with my S13.

I will give a quick back story to the car. I bought the car used last year and have been chasing wiring problems since the day I got it. It is an 89 coupe completely stock atm and is a 5 speed. It ran pretty good when I fist got it but always idled at around 1500rpm. After driving it for a while things started getting worse. It got to the point that the car just wouldn't start at all unless I pushed the gas pedal to the floor and cranked it for a minute which led to replacing all the vacuum lines which seemed to fix the starting problem.

Now comes the big problem I am having. The car is now idling at 2500-3k. I have replaced the MAF and TPS to no avail. I have done some searching and am now looking to pull and clean the IACV. There is another issue that has me confused though. The plug that goes straight into the TPS only has two wires (if looking at it bolted on, it has the bottom two and from what little I have found, the top wire in theory should be a ground). the TPS I put in still had the plug on it and that plug had 3 wires..... I have looking and looked but I can't seem to find this third wire in the harness any were and I am starting to wonder if there actually is a third wire in my car. I have tried looking but can't really seem to find any info on this. Could someone please clarify if there should be two or three wires plugging into my TPS and if there is anything else I should check/adjust?

I could really use some advice on this as this is my first real project car. I hope I covered everything and apologize for the long post.

[bonestock240sx]

well i had the same problem with my ka24de. mine ended up being the TPS that was messed up... are you sure you adjusted the tps correctly? to like .8volts or something like that? and my idle was about 2500-3 as well but i re did the timing and messed with the tps and the maf and it helped bring it down... then just recently i reset the timing to 20degree btdc and then adjusted the rest of the idle with the throttle stop screw which is a b**** to get at. idk if thats any help or not. and im not sure about the 89 TPS i got one when i had to replace mine and it sure as hell didnt match up to me 91 ka24de one. so maybe you got the the wrong one?

[Jim3798]

I am almost certain that I got the right TPS for it. though trying to to adjust it seems to get me no were (my luck I replaced a bad one with another bad one). though again I'm not sure if that would have something to do with the "missing"(if it is missing) wire. I am about to hit it with a meter and see what I get from there

[ls1240]

it could be ur distributer is 180 degrees off my s13 with sohc had same problem and after we turned the oil pump and distributer 180 my idle was fine after that and it still is but my car does have trouble starting i have to give it some gas sometimes when i start it it sounds like its off timing and it clicks and cranks fast but when it starts its miss firing so im not sure whats goin on with that