4agte idle problems

**reecegze** · 02-05-2009, 05:57 PM

Hey guys having a strange problem on my 4AGTE running bigport gze electrics and AFM.
Story is , recently the car is loosing its vaccum and idling funny on idle or down gearing to neutral. This is only happening every now and then for some reason it idles fine and runs like normal.. So its hard for me to pin point problem

I have checked all vaccum hoses , I/C piping etc for leaks but i am boosting fine. What could be causing the car to suddenly react like this ? ECU , AFM or maybe TPS ?

Any help would be appreciated as ive only had this issue with cracked vaccum lines and always found the problem.

Reece

**TERRA Operative** · 02-05-2009, 07:26 PM

Give your idle speed control a clean out. Pull it apart and give it a squirt with carby cleaner or the like.

**reecegze** · 02-05-2009, 08:09 PM

been reading that its possible that the 4agze AFM needs to be adjusted open more to let more air go through.. Maybe due to me runnnig 12psi threw it for 1 year.. Would this play around with my A/F ?

**TERRA Operative** · 02-05-2009, 08:19 PM

The spring can fatigue after a while. Apparently you can open it up and skip the teeth in the mechanism a notch.

You'll have to google how to do it. My GZE is MAP sensored.....

**feral4mr2** · 02-05-2009, 11:42 PM

there is also a air bypass on the afm you can open, it's under the cap to the side of the afm. when 1st turbo'd the feral i developed a stalling problem after wot or slight boost when coming back to a idle (pulling up to traffic lights etc.), adjusted the bypass a little and all was good.

**reecegze** · 03-05-2009, 11:01 AM

sounds like you had the same problem but mine was good for 1 year with boost.. my idle goes up and down from 1500 - 1000rpm and my boost gauge reads -30vac to -5vac whilst car is doing this. I give it a big rev and it goes back to perfect idle and -30vac.

**feral4mr2** · 03-05-2009, 11:08 AM

my problem didnt seem to effect my vacum/boost guage, just the running of the engine. was so long ago now i cant remember seeing the guage fluctuate anyways.

**reecegze** · 03-05-2009, 11:22 AM

Well i assume it would as the car would need to loose its vaccum to stall.. But the car runs and boost fine other then down shifting to nuetral and idle

**TERRA Operative** · 03-05-2009, 11:53 AM

Also check that there is no air in your cooling system. I have heard that this can cause idle problems as the sensor doesn't read the temp properly.

**reecegze** · 03-05-2009, 03:15 PM

Yer i thought about that but it cant be as ive never had these problems untill last week.. Now ive came to the conclusion that the AFM is rooted.. Car doesnt boost properly anymore or idle properly. I Tested the tps which was fine .. No vaccum leaks anywhere. Keeping in mind car didnt react this way for 1 year with 12psi turbo going through it.

So now i am after a spare 4agze AFM do just test it out.. If it turns out that the AFM is rooted i will go aftermarket ecu.. excuses

Also anyone know if there is any other 4a, 3s, series motor that is plug and play with the 4agze type of AFM

Cheers

**TERRA Operative** · 03-05-2009, 05:33 PM

The Supra AFM is apparently interchangeable, and larger in diameter too. You'll have to google the specifics (there is a guide around somewhere) as I've never done the swap.

**TERRA Operative** · 03-05-2009, 05:33 PM

.... double post FTL

**feral4mr2** · 03-05-2009, 10:15 PM

Originally Posted by reece12

. Keeping in mind car didnt react this way for 1 year with 12psi turbo going through it.

through it? where is your afm mounted, not that any specific amount of boost/air through it would ruin it IMO.

what do you mean the car doesnt boost properly?

**reecegze** · 03-05-2009, 11:28 PM

Here is my setup as you can hear it idle fine there.. Today the idling got worse and hesistated to boost for some reason..

I took the afm to check the insides seem to be fine :S other then the flap seemed very easy to open and wouldnt fully shut off which i think thats normal ?

Also i run a Bov venting to atmosphere which is not the best way to run the afm as it thinks more air is needed after t/b is closed.. Any ideas feral ?

http://www.youtube.com/watch?v=llY4e...e=channel_page

**reecegze** · 04-05-2009, 05:51 PM

Did some more testing .. Car boost fine 7/10 times i thrash it and then airflow seems to just stop and it feels like the turbo stops sucking air. Therefore all power is gone whilst accellerating.. Any ideas i am leaning towards AFM still

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