Celica Forums General Discussion General 2000 celica idle surge

Is it normal for my celica to idle at 1200 rpm and surges up to 1400 rpm repetatively? Goes up to 1200, down to 1400 up down up down

Cleaned throttle body and maf sensor and the problem is still persisting unless this is normal for a Celica to do.

This is normal until it fully warms up. It usually goes on for a minute or so when you first start. After driving, and while sitting at a light in idle, you may get fluctuation while the radiator fan turns on/off. Also, if you have the A/C on, you might get really low idle at times. Outside temperatures make a difference, in that that older low-revving engines are sensitive to extreme air temps.

When you say after it warms up are you referring to driving it? The cars unregistered so I can't drive it, but I have left it idling for 10 mins and the surging hasn't stopped

From my own experience, these cars don't really warm up very well just sitting while running. I've left my own car (2000 GT-S 6MT) running for up to 30 minutes at a time and when I come back to it it might be at the first temp gauge "notch". What you're describing is normal, though. My car fluctuates from 600rpm, all the way up to 1900rpm before it's warmed up.

Negative this is not normal. For the Celica GT with a 1ZZ-FE engine the idle speed should be 700+- 50 RPM to 750+-50RPM Whereas the Celica GTS 2ZZ engine should idle at 800+-50 RPM to 750+-50 RPM. Your idle should not be exceeding 850 RPM for whichever engine you have.

Surging in idle RPM's sounds like a vacuum issue. You could have an EVAP issue. Like something wrong with your Vapor Pressure Switch (VSV) or something of the kind. It could also be something in the Fuel Pump control circuit. It's difficult to know without an OBD code.

If the issue still applies, (actually, even if it doesn't, someone else could still benefit) head down to Advanced Auto Parts, and get them to plug in their OBD code reader, and get that code and post it here.