4A-GE MR2 mk1 aw11 - idle problems

[@FernandoSanchez-jp9eh]

Can you please re upload how to fix it?

[@gdiyta9419]

Did any of the problems go away with the new cap and rotor? Change that taped up intake hose stat!

[@davidglas4553]

Did you clean out the pvc and intake? They and the tps get gummed up by oil. Don't spray the tps though. Highly likely a vacuum leak on the intake as well. Many mechanics loosen the hose between the air flow meter spray carb cleaner in the intake and wipe it out with a rag. That plastic "hose" gets torn up and eventually leaks(sucks air). My 2c

[@andybateson]

Good luck with the resto. I'm doing the same to my mk1, it's a long journey!

[@d4a]

Sure is! But the end result will be worth it :) Good luck with yours too! I am taking apart the engine block this weekend and will try to make a decent how-to video, with some more explanations.

[@randywilson6816]

Thanks for the post. I really appreciate the help!!

[@Raevenswood]

MY 22re would miss once it got to operating temp and the RMPs dropped I went through everything ignition and fuel related and replaced the TPS, tested the AFM rebuilt injectors replaced fuel pump and regulator, all vacuum hoses new, sanded every engine bay ground to bare metal and reconnected, still couldn't find it ... I had tested the wiring for the ignitor to the ECU for continuity but hadn't done a thorough enough test to see that intermittently the wiring was dropping to 0 resistance meaning it was shorting out ... once it got hot and started vibrating with the engine running the wires started shorting randomly causing a mis and idle and at around 2-3k rpm range. since the wiring harness goes over the valve cover and the exhaust manifold and then to the ignitor on the driver side of the engine bay the wiring got cooked over the years and caused bad signal to/from the ECU and distributor. I was able to diagnose it as an ignition problem when I put the induction timing light on each spark plug wire and was seeing misfiring on all plugs ... I tried replacing the distributor pickup coil but they discontinued that a few years ago so I had to get a remanufactured distributor and that wasn't the problem either so it lead me down the line of ignition parts... the coil too not the problem but all of these ignition parts were out of spec ohm wise so they would have gone bad soon enough ... of course one I got to the igniter it can't be tested so I had to find a second hand one to test with and that didn't stop the issue either... super frustrating problem to track down. I only noticed it was the wiring when I set my meter to tone and got side tracked for a minute while the leads were still connected and it started dropping tone randomly then I was actually happy to finally find the problem :D I've never actually been so happy to find a short in my wiring before haha. there are so many factors that can cause misfiring on these old engines that use a lot of vacuum controlled parts but once you have gone through the process once it gets really easy to understand the symptoms and the possible solutions.

[@mitch5300]

I don't wanna say mine is misfiring but it has like a crackle tune going from 2krpm to 1.5k, noticeably especially at operating temperature and engine braking. Not sure if its my o2, cat, or whatever

[@yotasinthewild]

Bummer, your link says your account has been suspended. I'd love to read your blog about the idle issues and solutions for my 85 AW11, but can't open it.

[@d4a]

I'll be restoring the website tomorrow evening. I'll respond to this message when I do. Forgot to pay my hosting lol

[@Josstuka]

@@d4a they still no worky

[@d4a]

@@Josstuka I've closed down the blog sadly, didn't have time to maintain it properly anymore. But I can try answering any questions you might have here?

[@Josstuka]

@@d4a I don't really know what everything is called exactly so I can't be exact with my words but I'll give it a try. As the engine warms up there's a peg of sorts that will retract inwards and keeps the throttle on and slowly reduces it as the engine gets warmer (changes the idle). The throttle will continue to follow it to an extent and then stop leaving a gap in between the two. I tried adjusting the idle screw on the throttle, the one that's in the same area as that idle peg, and the actual rod that connects the throttle bracket to the throttle to no avail. Something seems to be stopping the throttle itself keeping it from going further any ideas? Before I tweaked everything it idled at 3000rpm now it's down to 2000rpm but there is that gap between that idling peg and the throttle.

[@HaroonKhan-lu4xu]

It sounds like a fuel air mixture issue. Check idle control valve and throttle position sensor. Volt meter idle tps around 0.6v and adjust idle screw accordingly

[@FernandoSanchez-jp9eh]

Sadly there is no more blog to get the fix.

[@deadgametech6624]

Looks like you found the answer? I would have checked compression at operating temperature. I know you say there is condensation coming out but it seems to intensify when it's heating up. Is that gas or water vapor coming out at the end of the video when you're revving? It's either super rich or blown head gasket.

[@d4a]

DeadGameTech I rebuilt the engine after the vid. Hg was in grear shape, rings decenr too. Culprit was the idle speed control valve, iscv, it ran super rich as you rightly pointed out.

[@deadgametech6624]

Good call, I'll look out for this with mine, thanks.

[@L3THALXFOX]

DeadGameTech really? My idle problem was a clogged fuel filter

[@caribshogun9772]

I think a combination of the tvis and emissions. Thats why in Japan 4age motors run aftermarket itbs and ecus.

[@bladeiii5173]

Wait so how did you fix that issue

[@jhunepapa1398]

What the problem and were the location of crankshaft sensor

[@caribshogun9772]

I'm in the midst of building my mr2. I have the feeling that i might have to replace intake hardware, might go itbs or carburetors

[@automatteck3477]

Mine idles at around 800 RPM - I got it running in about an hour after it sat for close to three years.

[@d4a]

@GDIYT A I cant reply to your comment for some reason. The button is missing. I replaced the taped up hose right after the video. It was the solution as you can see in the video description. However after that I had high idle. This was due to an improperly set throttle stop screw on the throttle body. The new rotor and cap solved nothing. The old one was completely battered, looked horribly and had a lot of residue everywhere inside and it worked just as fine as the new one. I was amazed.

[@harisansari6126]

have you checked your maf, sometimes a dirty maf can cause this.

[@d4a]

+Haris Ansari This car doesn't have a MAF it has an AFM. They work differently. You are right, a dirty MAF can cause a variety of symptoms, including some which are very similar to what you can see in the video. However if you read the description and check out the link you will see the actual causes of these symptoms in the case of the MR2 mk1 and other 4age 16v cars and a detailed instruction how to fix them. Thank you for your comment.

[@bigpapa1006]

2024🎉

[@justinsmit8097]

Did you ever get the idle/misfire problem solved? I have an 89 Mr2 that has the same problem. Thanks

[@d4a]

I did, it was the cold start system, a.k.a iacv (idle air control valve). There are links in the video description with a more detailed explanation.

[@jjbc5059]

@@d4a hi m8, the site is down. Where can I find the info? Thanks in advance 🙏

[@Castle_Elizabeth]

@@d4a thanks bro can you send me the link to the idle control valve i am going thru the same issue currently

[@masonshackelford1360]

How did you fix the air control valve? Did you order a new one? Or clean the old? I can’t find any new ones for an ‘86 and am not sure what to do.

[@d4a]

I deleted it and held the throttle open for 30 seconds on cold starts 😂

[@masonshackelford1360]

Is it not needed after the engine warms up? Thank you so much for your time.

[@marlo0oty213]

@@masonshackelford1360no and you can add ac solenoid for cold starts

[@qordone9281]

Vacuum leak or dirty injectors. Why no oil pressure? Is the wire connected to the sensor?

[@d4a]

Check out the link in my description. My initial problem was a vacuum leak. But then I ended up idling at 1500 rpm. That was due to the throttle plate stop screw needing adjustment. I read a lot of posts of people with this and similar problems with the 4A-GE 16v and its almost never the injectors. They are one of the strongest links in the chain and go faulty very very rarely. The pesky Idle Speed Control Valve wax pellet thing (ISCV) on the throttle body is the most common culprit, followed by vacuum leaks that you mention. There is no oil pressure because there is no wire connected to the oil pressure gauge :) I bought it that way. Am currently in the process of completely restoring my MR2 mk1 and will fix that eventually as well. Check out the link in the description its my blog of the restoration (and other unrelated stuff :)

[@rhondabridgeo5674]

I know one thing that hasn't been looked at or discussed that is common with a 4a-ge. Oil pump. I have been running mine for months by just keeping the vehicle over the 3000 rpm but keeping the gas pedal pressed at stop signs. This is most likely one or thee reason. Lower oil pump not good. Ive asked my Toyota mechanic friend who drives his MR2 daily,. George

[@wink8530]

Ever get this figured out? Just curious

[@dragospahontu]

This is for the scrapyard

[@wink8530]

@@dragospahontu what do you mean

[@johnlowe9940]

it may be your idle pulley it may be freezing up check it. Look down over on the belt side look for a needle thing on the timing cover.

[@d4a]

Can you please explain what do you mean by freezing up?

[@johnlowe9940]

your timing belt run on this pulley as you look at you cover in the middle of it you will see a little needle point sticking out. It look like a little wheel that turn and spends as the belt roll over it "But when they get stuck the belt slide not roll and caused the timing to misfires because it been slow down because the slide on this pulley beside rolling over it freely. "a example "a skateboard wheel "look just like this pulley "when it don't roll free its stop the speed .AND CAUSED THE CAR TO MISFIRES. ONE REASON.

[@alexchulzhanov]

I have this same problem but it's only when I cold start or start the car up after it sitting for a little while. It'll idle very low and barely responds to throttle until I run the engine for a bit. Then it idles at like 800-1000RPM. I do have a K&N intake but I'm not sure if that's the problem.

[@d4a]

+byalexandr K&N can't cause that. 4age engine?

[@fernandoramirez0927]

my aw11 is having the same idle as you what did you do to fix it? i daily my mr2 and really want to fix the problem as fast as possible, thank you

[@bradcogan8588]

Fernando Ramirez did you sort it? Best way is manual choke conversion

[@fernandoramirez0927]

How do i do the manual choke conversion

[@karoliskazlauskas1213]

Brad Cogan yeh the 4a-ge has a efi not a carbiurator

[@randywilson6816]

@@bradcogan8588 hi Brad. I have been wondering about that auto choke. Mine idles at 2000 and surges. Going to try the air cleaner and the idles air control valve. But how do you check that choke on these. And of course buried under the intake smh

[@bradcogan8588]

@@randywilson6816 yeah just take it apart and clean it, should improve things a little. Sometimes they are just beyond repair though. Best way to test it is to fit it to the car, really. Fire up the car and see what it does. Adjust the idle screw so it's at 800rpm when hot then when the engine is cold again the next day or whatever, give it a go starting it and see where it idles. Anywhere between 1200 to 2000 I'd consider normal for a cold start. If it idles really low like 600rpm or stalls/won't start without bringing the idle screw back up then yeah, it's toast and you'll just need a new iacv or do a manually selected choke conversion.

[@aranibiswas2124]

10 years 😄😄 completed

[@alundrasrt]

Hi, with a MAF 4AGE, can I remove the intake duct and test with my finger? Thanks.

[@d4a]

There is no MAF (mass airflow sensor) on the 4AGE. It either has an AFM (air flow meter, the big thing with a flap in it) or MAP (manifold absolute pressure) sensor. You can do the finger test on both as far as I'm aware. Be ready to get pinched on your finger a bit.

[@alundrasrt]

@@d4a Thanks for the correction and the advise I'll check for sure. Anyway I'm stuck with my diagrams about the front radiator fan lways on. I tried ALL wires and can't find why it's in safe mode. Any advice?

[@d4a]

Try the engine bay temperature sensor or the ecu coolant temp sesnsor. They might be faulty and telling the engine it's hotter than it is. Or it could be the fan relay, but I doubt it.

[@alundrasrt]

@@d4a Yes, i checked each relay with 12V and they still works perfectly. I'll replace both sensors because I only checked their resistance screwed in. Thanks

[@shockwavemikey64]

looks like you are burning a little oil as well after that last rev!

[@d4a]

+Travis Lakey I definitely was. The engine wasn't in proper condition which is why I single-handedly took it out of the car and took it apart. Had zero mechanical experience back then. Its still close to zero now, but a bit better. Hope to have it back in the car by the end of they year. Wish I had more money, time and money.

[@sharingiscaring9320]

I have an identical issue like this on my 1989 MR2, and I just got it fixed today (8/23/19). I took apart the throttle body and cleaned with sea-foam. I spread Sea-foam into the the throttle body, soaked it, and removed everything. I polished the plate on both sides to clean all the carbons deposits. I also spread Seafoam in the intake-manifold, soaked it overnight, and brush with a plastic brush. I dumped sea-foam into the piston chambers and soaked for 2 days. After they both cleaned the low idle issue after warm-up and misfired are fixed. The engine runs smooth like butter and felt more powers.

[@KaranvirSinghUK]

I have the exact same problem with my MK1b. Its so frustrating and I am struggling to find out what the problem is. Every single thing you have described in this video is exactly what is happening with my car. What was the solution to this? Thanks for your help

[@d4a]

In my case it was the idle air control valve, IACV. In 9 out of 10 cases like this it's that

[@KaranvirSinghUK]

@@d4a That is helpful. How big/small of a job is that?

[@d4a]

Small-ish. It's on the throttle body. Can't be fixed, must be blocked off and then you hold throttle manually for 30 sec or so for cold starts.

[@XPFTP]

injector break down with heat. do a ohms test on them if you havent got to them yet bein 7 months ago.. if i remember . most injectors should be around 14 ohms and above. if there in the 10ohms or below bang bang

[@ariyapol1111]

I hate that wax pellet air control valve thingy. 2 out of 4 4age powered cars my family own had that problem.

[@d4a]

IKR. Toyota really messed it up with that one.

[@sotektechnical439]

+driving 4 answers (mr2 mk1 hero) can you please explain what he means. I am not familiar with the wax pellets

[@TheOrdep1976]

It looks like u got new wires maybe spark plugs cap and rotor then fuel filter

[@d4a]

+TheOrdep1976 That's the usual procedure for faults like this. But for this engine, the 4age bigport, in 90% of the cases its vacuum leaks, throttle position sensor, bad timing, and a worn wax pellet in the ICSV which causes high idle. The first thing I did was what you suggest - replace the plug wires, distributor cap and rotor and spark plugs. The plug wires were so bad that they would give you a shock when you touched them and the distributor cap was in horrible condition. The weird thing is that when I changed them they improved nothing. Everything was virtually identical before and after so I dug deeper into the above mentioned underlying causes. These old school machines aren't as fragile as the stuff they make nowadays, they are sometimes capable of running fine with very worn or bad parts and its often the small and inexpensive fixes and tune-ups that make the biggest improvements.

[@theantisocial1-]

My aunts 96 Honda Accord has the exact same thing except way worse. I think it's the exhaust system, but, i dont know, im not a mechanic.

[@d4a]

+Joel Suarez Its rarely the exhaust (although it might be). If its a significant leak in the exhaust system you will definitely hear it. If its only bad while idling and goes away once you rev it, its most likely something to do with vacuum leaks and/or the intake system. I don't really know much about your particular car so I'm just making an educated guess. But what I do know is that its an annoying problem. On the other hand, unlike modern money pits which utilize overly complicated fragile technologies in order to increase the mpg by 2%, 10, 20 year old and older cars use proven, simple and effective technologies, so if there's no oil being burned its most likely a cheap and simple fix that you might be able to handle yourself by researching a bit, learning in the process and saving a few bucks (probably won't save anything as you will have to buy a set of wrenches or some other tool and make your first step into petrolheadness i.e. financial destruction - but its fun financial destruction).

[@jasonchuayap]

I want to say you have poor compression. it's common among the older mk1s

[@d4a]

+Jason Yap Thanks for your comment and keen observation :) I removed the engine and its currently being rebuilt. You are right, the compression was below desirable. But compression itself isn't the source of the idle related problems, its other stuff you can read about in the link.

[@artempavlov4599]

maybe an oxygen sensor

[@dillonryan9330]

Headgasket no doubt

[@innovision777]

Head gasket bad ...... :-( or Cracked head...., That would account for running good till hot, when hot the crack exspans...

[@d4a]

+innovision777 These symptoms are almost never caused by a failed head gasket in case of the 4AGE, and rarely in many other cars as well. The head from this engine was removed and inspected. Head is definitely 100% ok as well as the head gasket. Check out the link in the description and the comments below, causes are almost always the wax pellet in the ISCV, or a vacuum leak, or the throttle stop screw or any combination of these.

[@dragospahontu]

Wtf is this

[@batteryjuicy4231]

did you fix it?