Hey I was just wondering if someone knows much about these engines! I have a 91 trueno and its blowing black smoke. I have got opinions from 3 different mechanics and they all tell me something different. First one said it may be valve seals, other one says its oil residue in the exhaust because he reckons oil was over filled and third one said its something to do with running to rich. It blows out smoke every time I change gears when I accelerate and it's a lot of smoke. And just wondering if anyone could clarify what it may be! Because I am confused. Thanks :)
pollymay,
Oct 5, 4:48am
Black is fuel. That have a regular 4age or a silvertop 20V!
In any case bridge TE1 and E1 in the diagnostic terminal (turn car off first) after a run in the car and then turn the key to the on position. Count the flashes of the check engine light. This gives you a fault code, may or may not tell you anything but it's a first step and free/easy one.
toyota_fan93,
Oct 5, 4:52am
It's the silver top. And I have done diagnostic test, and didn't give me any codes, I'm thinking it may be the oxygen sensor or the ECU because the mechanic put in a new one and didn't reset it or anything. But I'm guessing that would come up as a fault code when checking it!
pollymay,
Oct 5, 4:56am
Ecu rarely fails. A silvertop I'd be looking at the O2, the TPS and the AFM as my first stops. The O2 is common to fail, you can unplug it and see if it's any better, the TPS you can actually do the same. The AFM not so much. There are service specs you can test the various sensors for but I'm lazy as hell so just unplug them and look for improvement, usually tells me what I need to know anyway.
r15,
Oct 5, 5:12am
is it much black smoke!me and a few mates had 4age silvertops 12 years ago when they all had low kms, and they all smoked when you gave them a bit of shit
toyota_fan93,
Oct 5, 5:29am
Yeah it's heaps of smoke, when it was at mechanics this afternoon he revved the guts out of it and massive clouds of smoke came out, it's quite embarrassing driving it like that. I would like to figure out what's roughly wrong with it so I can tell mechanic because people I bought it from gave me a warranty and I think they just fobbing me off so they don't have to fix the problem. I have been doing a bit of research on the net and a lot of people mention that their 4age motors smoke, if it was a little bit of smoke it would be ok but its not just a little bit :-/
pollymay,
Oct 5, 5:48am
Well it entirely depends on the colour, blue or light grey is oil smoke, black/dark grey is fuel and pure white is steam or water. If you are 100% it's quite black then it should be fuel. My 20V had bad injectors, cleaned them and it was worlds better, at this age it's another common hiccup
toyota_fan93,
Oct 5, 6:10am
Yeah it's definitely black smoke. And doesn't help that the car has high ks, was thinking about getting a motor and just do straight engine transplant , but since it under warranty ill try get it fixed if the mechanic will actually do the job properly, the first time it went in they thought it was the wrong grade oil and oil was over full, so all they did was change oil and they put thick oil in it, and its also using oil, I took a trip to ashburton and back to chch and used about 500mls of oil, but was driving it fairly hard the whole way but it still shouldn't use that much really!
snoopy221,
Oct 5, 6:14am
Catch 22 is excess fuel dilution will cause some oil usage. grab ya phone book and have a look for neal stuart automotive in ch ch. K mention this thread- A second opinion could be handy- Or a t least a qualified one.[going by the track record.-LOL]
toyota_fan93,
Oct 5, 6:25am
Ok sweet thanks for the suggestions! Will suss out that place snoopy221.
ola_bitchola1,
Oct 5, 2:51pm
high ks shouldnt matter too much i had a ae101 with 350000 on it when sold id get it looked at properly if its using that much oil it may well be the valve stem seals
hrt,
Oct 5, 5:30pm
The ECUs are quite well known for failing in these, capacitors inside leak and give random running issues.
Running rich and using oil may be unrelated issues however. The higher km ones do tend to use a bit of oil, especially if you're giving them a bit of a hard time. Even if you have no codes in it there may still be an issue with the likes of the AFM. If it is reading high and overfuelling, but not going out of range, then you're not going to get a fault code.
pollymay,
Oct 5, 6:04pm
The blacktop not really the silvertop I've found. The blacktop also blow the vvt engage transistor all the time.
toyota_fan93,
Oct 5, 8:05pm
Yeah one of the mechanics I spoke to said it may be valve stem seals, but I'm guessing that will be an expensive job. So I'm hoping it will be something simple and cheap to fix. Not that I should be paying for it because its still under warranty. I did notice when I looked under the car some wires have been cut, I thought it was o2 sensor but I think it may be the warning light for when the cat converter gets too hot, it has wires attached to exhaust then looks like a sensor going into the chassis of the car!
v8power,
Oct 5, 8:37pm
You keep mentioning all these mechanics you take it too and their idea of what is at fault. Are these mechanics trade qualified because everything you post on here from them seems to be oil related.
If your blowing black smoke then you have a fuel related problem.
I would start by finding someone who knows what they are doing to give you a correct diagnosis.
Start with the basics, check air filter and inlet track isn't blocked, check plugs are producing a good spark etc. eliminate the easy things first then seek qualified assistance.
dent,
Oct 5, 9:12pm
the 4age engines of that era did have problems with there ecus. Quite common and can cause rough running, black smoking etc. Dose the vehicle seem to be running ok other wise. Starting alright etc!
toyota_fan93,
Oct 5, 9:14pm
Yes all the people I have spoken to a trade qualified lol. But you wouldn't think so because they all think its oil related except one of them. I have just checked o2 sensor and it is pitch black. It has brand new air filter so not that.
toyota_fan93,
Oct 5, 9:16pm
Yep car starts fine and runs all good, just the black smoke, and sometimes when I turn the key it doesn't start like it has dead battery but I'm pretty sure it's to do with the alarm not dis arming properly but could be wrong, I'm no mechanic lol
dent,
Oct 5, 9:17pm
dose it matter if hot or cold!
toyota_fan93,
Oct 5, 9:18pm
Nope, smokes both hot and cold.
dent,
Oct 5, 9:22pm
id be checking airflow meter, temprature sensor and ecu. If it dose it when cold that kinda rules out o2 sensor as that dosnt operate till sensor has warmed up.
toyota_fan93,
Oct 5, 9:27pm
How do I check the air flow meter! Probably a stupid question lol
pollymay,
Oct 5, 9:27pm
The later ones were heated, they operate from the get go iirc
dent,
Oct 5, 9:28pm
its not easily to do or explain! either need a scope or scan tool to do properly. Any good mechanic should be able to do some checks.
toyota_fan93,
Oct 5, 9:30pm
Ok, it's supposed to be going into mechanic on Monday, it can only go into one mechanic cos of the warranty the car dealer only deals with one mechanic. So will mention what has been said in this thread and see what they say.
Since the public registrations are closed, you must have an invite from a current member to be able to register and post in this thread.
Have an account? Login here.