Gen2 3SGE Idling problem - Take 2

[alliance_22]

Okay. it seems the idle problem is here to annoy the crap out of me again. I thought i fixed it last time by cleaning the appropriate parts...

After finally getting the air con in place, which took 290 or so dollars, the air con wasnt really cool either .. but the thing is the idling problem have returned!! and nearly caused me a big accident today! Engine cut out while in traffic going down hill... if it wasnt for the handbrake... i'd be responcible for 3 cars in the Gorhill freeway.

The engine mostly idles at 900-1K rpm... and can suddenly idle at 400-500rpm after a small run.... when that happens, you can rev it a bit and it brings it back to 900-1K rpm, but this dont always work as sometimes even after 20min of driving, it can idle at 400-500rpm.

Just today, esp when the aircon was on, it was idling really unstable at 900rpm sometimes and at 1300rpm at other times... and finally droping to 300-400rpm and finally Cutting out everytime.

I'm lucky to keep it in one piece going to work.... it died 3 times in the car park

My car is a 1988 Celica ST162SX with a complete Gen2 3SGE conversion.

Thanks, any help will be appreciated.

Cheers,
Chopin

[hamgatan]

vacuum pressure leak in your intake by the sounds of it.

had the same prob in my 7M before

[alliance_22]

That sounds like a real possibility.... how'd you go about fixing it?

oh and through the air box i clearly hear a low Humming sound

[hamgatan]

mine at the time was due to the crappy factory bov releasing too much into the atmosphere and it was creeping... i changed it to a stronger bosch one from the saab and plumbed it back into the intake before the turbo and it was right as rain..

but in a NA 3SGE you dont have that issue.. maybe AFM is dodgy or leaking around your filter somewhere?? that would be the most likely bet i think...

[RWDboy]

Just check anything rubber that's part of your intake that is between the MAP sensor (somewhere near the air box) and the manifold. Also check all the rubber hoses that are part of the engine management or emissions equipment. If air is getting in to your engine and the MAP sensor don't know about it - your idle will go all over the place.

And if you engine does stall - *DON'T* rely on your handbrake. Just press the foot brake really hard - the brakes are still fine, they just don't have any assistance so the pedal is extremely hard to push, but you can still lock 'em up with enough effort.

[alliance_22]

Thanks RWDBoy i'll check it tonight... i'm thinking that the sensor may be faulty.

[hamgatan]

err...since when did the gen 2 have a map sensor?

[alliance_22]

Its a little stick thingy that sits in the airbox. i first thought it was a tempreature sensor of somesort, but i can be wrong.

[hamgatan]

i didnt think gen 2's had a MAP Sensor... i thought they were AFM based, that the MAP sensor was only introduced in gen 3's..

[alliance_22]

i didnt think gen 2's had a MAP Sensor... i thought they were AFM based, that the MAP sensor was only introduced in gen 3's..

I So dont have a AFM on my car... check it out

[matt86sx]

Yeah the little stick thingy that sits in the airbox is the air temp sensor.

Here's the Gen 3 MAP sensor on my car (the little black thingy with the blue sticker on it mounted next to the chassis no plate), maybe yours looks similar to this? Not sure where this would be situated on the Gen 2's though. You can see on mine where the hose connection leads to in the foreground, right next to the oil cap and above the brake booster vacuum line.



Help you any?

Matt

[hamgatan]

I So dont have a AFM on my car... check it out

hmm ur right.. thats weird. i was under the impression gen 2's were all afm..

[RWDboy]

afaik - Gen 1 3S-GEs are AFM, Gen 2 and onwards are MAP.

3S-GTEs are a different story.

[alliance_22]

Yeah the little stick thingy that sits in the airbox is the air temp sensor.

Here's the Gen 3 MAP sensor on my car (the little black thingy with the blue sticker on it mounted next to the chassis no plate), maybe yours looks similar to this? Not sure where this would be situated on the Gen 2's though. You can see on mine where the hose connection leads to in the foreground, right next to the oil cap and above the brake booster vacuum line.



Help you any?

Matt

Bro !!!

Strangely enough!!!!

I CANT FIND MINE!!!!

[alliance_22]

Okay my bad, i found it!!

All hoses seems to be connected okay...