Idling high, 1100-1200 rpm Options

[6gsillyca]

Alright, so after finally getting a bunch of piping back from powdercoating, I was able to put everything back together, and start it up for the first time since putting it away for the winter last season.

Things I did during the winter:

swapped out the 540's for stock 440's
swapped out "possible chipped" JDM 93 ECU for 91/92 USDM ECU (both for SW20)
new plugs, ign wires, coil wire, cap, rotor
powdercoated valve cover, new VC gasket
powdercoated TB bracket, everything up until IM was removed
new (rebuilt) HO alt (120+ AMP)
new pass cv axle
deleted metal "plate" that runs behind fuel rail with vac line for FPR. Now running vac line routed behind engine, tucked along firewall.
throttle cable is NOT adjusted properly, since I can't get it to idle properly

I started the car up and it runs, but very rough. It will almost die, then shoot up to ~2k, then cycle back down to >400rpm, and almost die again. Goes through this cycle, and each cycle is maybe 10 sec long. Exhaust is not overly fuel rich (not much carbon splatter either), but it is spitting liquid. I don't know what it is, but it is very watery, no gasoline smell, and is a light black color.


Another thing I did notice with the new (91/92 USDM MR2 ECU) is that I now have a CEL. I was not able to get it to light up with my old JDM ECU. I was also able to pull 2 codes. 21 and 51.

Will look into the CEL codes, but it was running good when she went away last year...




EDIT:
Got it to idle good now. Turned out to be a missing FR insualtor, giving me a big air leak. Fixed it up now and it idles good, but high. 1100-1200. Any idea's?

This post has been edited by 6gsillyca: Jun 5, 2008 - 3:30 PM

[lagos]

Why is that. Shouldn't closed loop mean no sensor input? If it is idle then the ECU should be able to run the engine off stored maps.

No, like I said, you have it backwards. Closed loop means the ecu is running off the o2 sensor. This happens at idle and cruise only. When you floor it, the ecu uses stored fuel maps and ignores the o2.

Either way, I do have a replacement sensor on its way. I find it odd how the o2 sensor was good last year but bad now. I think it may have been faulty before I took out it anyway, but with my jdm ECU I didn't have a CEL, and now that I do, it is able to give me a code.

Unless you forgot to plug it in, I really doubt your o2 just went bad for no reason. You probably bought an ecu from another year car, that has the o2 inputs on different pins.

Why did you take out that ecu in the first place? Was it giving your problems?