4A-GE Idle Issues Guide

[@MoleskineFan]

I had a similar problem in my AE86, replacing the TPS solved it, but you make some good points here! Good video, subbed :-)

[@carlosmayorca4642]

Thank you so much for this! I already replaced the TPS, my EGR valve, vacuum hoses, spark plugs and I was still having the same issue. I'm going to try this and hopefully it will solve it!!!

[@pateenmacd8079]

did it work for you?

[@carlosmayorca4642]

@pateenmacd8079 my issue ended up being solved by adjusting the butterfly flop. The throttle body was a bit too open and it was letting too much air in

[@awong160]

Hey KP, I currently have this problem with my 87 AW11 MR2 with a 88 4AGZE swap. I'll be using your video as a guide to help me. Thank you! -Alvin

[@southcongress]

Worked perfect on my MK1 MR2. Thanks!

[@TheCorollagti]

Hey mate, that's great to hear. Sounds like a fun motor! :D

[@TheCorollagti]

The coolant should force its way through rather than go into the overflow - the overflow is only active when the engine is running very hot (there's a pressure requirement in the radiator cap to let it work) and the coolant will find it easier to get through the system rather than the over-flow. Make sure you don't rev the engine without covering the radiator water inlet otherwise it goes everywhere xD Your main worry is working those coolant pipes to the throttle body! Get them flowing coolant!

[@iLouieTube]

Hi, replaced my radiator and coolant, ran the car and all the air out, but my car will not idle it stalls straight away, what should I check please? Also keep backfiring I did replace seals in Cam angle sensor, I've tried to adjust it forward and backwards it helps alittle with the backfiring but will not idle just dies

[@pateenmacd8079]

did you solve this issue?

[@FiveIronFrenzyFK]

Mr. Parris, Yesterday I did a 'proper' bleed of the coolant system and its still hunting. I'm hunting from about 1,500 --->1,000. I'm now considering trying this and I had a few questions. 1. When you squeze the hoses doesn't all the fluid just go into the overflow instead of forcing its way through? 2. Doesn't leaving the cap open cause the fluid to overflow instead of air getting out?

[@H0tDawgWater911]

im having this problem, you put the radiator cap on part way?

[@TheCorollagti]

Check the Auxiliary Air Valve isn't jammed shut. Is the cold start injector always on?

[@dwoodcob]

@K Parris-Jones Great Video thanks for the upload. I have a 4agze with a hunting issue only on cold start. It will float move between 850 and 1500. Once the engine warms up it goes away but the idle is a bit eratic and rough. Could this fix my issue as well?

[@kynanparris-jones6768]

dwoodcob Hi mate. That sounds like a similar issue however I am unfamiliar with the 4A-GZE and thus I don't know if it uses the same cold start system. I recommend you try using this guide to see if it helps. Failing that you can always make a video and send it to me and I'll be in a better position to help!

[@dwoodcob]

Kynan Parris-Jones thanks for that mate. I will give that a go this weekend and see how it goes. Any help you can give will be great.

[@kynanparris-jones6768]

dwoodcob youre more than welcome. Ive just started a new channel and I will be reuploading revised versions of these videos including multiple videos on general restorations and mechanical procedures. Feel free to subscribe and ask for advice any time!

[@donavenable]

Mr K Parris Jones..thank you putting this video on youtube. But, did you know that if your radiator from heater underneath of dashboard is damaged or not working correctly with no heat from it. Your cold start would still work and underneath your throttle body of TVIS airflow intake, this unit that has one outlet to hold the heated coolant water, this allows for the cold start to react. lt's a spring chamber unit and inside if you take out is spring built inside the unit, this is simulator to the Honda cold start unit but only difference is in a Honda, you open the unit out with flat screw driver, clean out the dirty carbon built by air with dust mixing. lf you do not clean it and test the spring inside if has resistance or not to hold pressure inside of the chamber. The cold start isn't going work, and the cold start unit below the throttle body is also a common problem so is radiator underneath the dashboard. But if you have these this problem these are two common issues. I bought a 1987 TOYOTA CONQUEST RSI TWINCAM, but it cold start wasn't working. My previous owner son inlaw disconnect cold start, and reconnect the pipes that lead to cold start back to engine block...So, i had to deal with issues and thanks to your video, it helpful to explain me reconnect of cold start.

[@dunersguy]

i have same problem atm with my 4agze motor and aswell as that it iis over fueling injectors and keeps throwing knock sensor any ideas hw to fix it have replaced motor wth a small port gen 3 motor 4agze old motor was a bigport gen 1 any help would be great thanks

[@iiiOoZiEiii]

hey i have a gt to your model and i was wondering where did u get your headlights from?

[@jcadlols]

This happened to my dad's race car once when it had a 4age in it. Our engine builder was there and as soon as we said what it was doing he said it was an airlock. I think it's a pretty common occurrence with the 4age's. Haha

[@TheCorollagti]

They're notorious for it, but once you get the technique down for a coolant swap it's easy enough to solve. :)

[@phv757]

Mate your trouble is with the Throttle Position Sensor...Just Replace it. It cured mine.

[@TheCorollagti]

No its not mate the video leads you through the fix :P It's fine since doing that!

[@TheCorollagti]

Nice random dislike there xD Anyway, I just watched right through it bud. Check your Flash Player settings, internet connection (usually helps to have one) and try to load it from a different browser etc. ;)

[@WarlDogg]

your video stops at 34secs

[@cyskation059578]

Cool

[@MatrixGarageCarbondale]

As always youtube never failing to disappoint. First off posting what your issue was is silly because there are many things that can cause high idle and surging. For every person this helps fix their problem that just happens to be the same as yours you will leave 10 people walking away disappointed and confused because their problem was not the same as yours. Instead of teaching people how to properly diagnose their car you assume that there must only be one solution for this problem and give them that solution. Even for that solution no 4AGE should take more than 15 minutes to bleed. An AW11 only takes 10 min to bleed and it has another 20 feet of cooling system. There are many reasons a 4A can have high idle or surging and air in the coolant in my experience isn't even the most common one, although it is the one that everyone regurgitates all the time because they don't know any better.

[@TheCorollagti]

Matrix Garage thanks for the feedback. I'll make sure to not tell people what issue I am solving if I ever make a tutorial again. The ambiguity should help things along for the beginners. Sarcasm aside, I appreciate that there are many other faults that cause this symptom; I felt it would help others (which other comments show it has) from scratching their heads for so long as I did when I built the car at age 17. Sadly I dont have the time to take up KZbin seriously ie making tutorial videos; there'd be too little time to build my other cars if I did so. If you are frustrated because you need further advice, feel free to contact me personally and I'll try to help out.

[@3cila819]

Haha that's funny. Here is the guide I wrote which actually tries to explain proper diagnostic path and all potential possibilities for high idle and surging. For those who still know how to and care enough to read. www.matrixgarage.com/content/understanding-and-diagnosing-surging-and-high-idle-4a-ge-4a-gze-and-other-l-jetronic-systems As always youtube proving that amatures seem to be the only ones who have time to make crappy how to videos with more misinformation and bad advice than good.

[@3cila819]

KZbin for the how to water your plants with Gatorade generation.

[@TheCorollagti]

Good on you for writing a proper guide! May use it myself given I'm such an amateur 😂😂

[@TheCorollagti]

The coolant should force its way through rather than go into the overflow - the overflow is only active when the engine is running very hot (there's a pressure requirement in the radiator cap to let it work) and the coolant will find it easier to get through the system rather than the over-flow. Make sure you don't rev the engine without covering the radiator water inlet otherwise it goes everywhere xD Your main worry is working those coolant pipes to the throttle body! Get them flowing coolant!