6G Celicas Forums

So some of you have followed my progress with my 94 2.2 gt. I had put a jdm engine in the car. Since i did so, the idle has been too high, around 1500-2000 cold start then down to 1000-1300 warm. I tried vac leaks, map sensor, mass air flow sensor, checked timing, i am completely stumped, the car is running really rich and poorly. Its killing my gas milage, and im out of ideas. PLEASE HELPPPPP

Oxygen sensor?

Check your temp sensor, the one the ECU use to set the air/fuel ratio at cold starts. Check it cold to see if the temp readings are close to the actual outside temp.

idle air control valve?

how old is the distributor? my distributor had 200k on it and it finally went bad.. it was stayin advanced and there fore flooding my engine and it would stall out and stuff. the car was running WAYYYYY to rich.. i would MAYBE think about checking or buying a new distributor bc ur coil inside of it could b bad.. thats my thought on it.. goodluck

I'm gonna go with engine temp sensor on this one too, unless your TPS just needs adjusting. Or for that matter have you tried just adjusting your idle at the throttle cable?

This is very true. If not you should also check and make sure your throttle body gasket is not leaking and that your throtle body plate is closing completely.

Good Luck.

Hey guys sorry it took me so long to respond. So i changed the tps, it wasnt that, I sprayed carb cleaner all over the throttle body, it wasnt that. The 02 sensor isnt pulling codes, Which by the way it isnt doing when i unplug it either(wtf). The distributor and coil are new and fully functional. Ive been driving the car around like this for almost a month now. Also how do i check that temp sensor? I know the temp gauge in the car is functional ad accurate. Also how do I check the idle/air control valve? THanks guys

iirc theres two sensors. one that runs the gauge and one that the computer uses. you'll want to replace the 2 wire temp sensor, not the one wire temp sender. it does sound like thats your issue to me as well. codes take forever to pop up on OBD1. i drove for almost 8 miles with my trans connector unplugged before it threw up a code! so just starting the car for a few minutes with the O2 unplugged may not throw the code, you'd probably need to drive several miles and make 2 or more drive cycles. toyota OBD1 uses a 2 trip fault detection. the problem must be present for 2 consecutive drives before a code will set, however you can put the car into check mode via jumpers in the diag port to cause it throw codes as soon as the problem occurs. good for chasing an intermittent issue.

You probably just need to adjust the ignition timing on the engine with a timing light.

good thinking, i assumed that the engine was otherwise in proper working order.

In the case of a faulty temp sensor, the ecu will not light the check engine indicator (unless there's a cut wire).

If the temp sensor reads an inaccurate temperature, the ecu have no other way to know if it's accurate or not, it will assume that this is the exact temperature. The air/fuel ratio will be too rich (or too lean, depending on the situation) and the car will have rough idle and poor performance, depending of the situation again.

2 ways to check it, 1st, with a scan tool to see if the temp readings are close to the ambiant temp. You must have it checked cold (cuz your problem is about cold fast idle). With apropriate scan tool connected, start the engine and watch the readings to see if it's close to reality.

2nd, with a multimeter, check the ohms refering to a chart with the ohms/temp values of that particular brand/model.

Faulty temp sensors can have accurate readings in some temp range and inaccurate readings in other range, so you have to check it in it's full temp range, from very cold to fully hot.

I strongly suggest to have it checked by your local shop with a scan tool, it's much more accurate and it will cost you only a few bucks.

Hope you'll find your problem soon. Let us know, it might be helpfull for others.

ok ill check those things tomorrow, it isnt just cold start that it idles high though, im assuming my idle should be around 750-850 warm. It sits at 1100-1300. hope it is that sensor. i did check my timing though, its set 10 degrees. so thats not the issue. I also wanted to ask. I only have one 02 sensor, and ive heard of people on here having two. Should I have one or two?

fed spec will have one, cali spec will have two. emissions sticker under the hood well tell you if you have fed or cali, but since you swapped engines...dunno anymore. jap spec? lol

Did you check the throttle body butterfly? as in is it fully closing? I would back it off until there is slack and see what the idle does then.

spelled "genius" wrong lol

usually Ive seen motors being changed or swapped in, the timings bad.

Haha Crap