Expected Lifetime of a 4AGE

[varix]

Basically I am keen to judge the lifetime of my motor, have looked around toyspeed at various subjects like big end bearings, blowing smoke etc, and would like to post this to see what people that are likely more experienced than me have to say. I realise this is only a forum not a mechanics shop. I just want to see if it is going to be worth my time on doing some minor work on the car, rather than it blowing up on me and the work being pointless.

The motor is a Red Top Big Port 4AGE in a 1988 AE92 Trueno and has done 210,000ks

1.
When idling the motor seems quite rough, when idling at around 700rpm it makes the car vibrate slightly, nothing serious but not what you would expect from a newer car. Once holding the revs between 1500-3000 the car sort of bubbles/pops. The car has a canon muffler, and it is easy to hear the pops coming from the exhaust and the tacho shows a quick drop in revs (only small) before going back to where they were held, the pops probably happen about every second. The car has a pod filter and thus no air temp sensor and the ECU spits code 8 which is "no/failed/disconnected air temp sensor", which may cause these problems?

2.
The engine makes some weird clicking sounds, seems to be coming from the head but could just be the injectors? Also makes a sort of grinding sound, from lower down in the engine, although not very loud. It could be noted that the car has made these sounds for well over 10,000ks so if it is something like a big end bearing (which is my fear) then it should be long dead by now.

3.
Car consumes about 5 litres of oil every 6 weeks. And is probably driven about 30kms on average a day. No oil on the garage floor. Smoke is minimal to none at low revs, becomes black/slightly blue at higher revs in moderate quantities (can be seen in the rear view mirror, but not giant plumes). Probably quite normal for an engine this old?

It could be noted the car runs pretty sweet and has done for about 30,000ks with only oil changes done about every 10,000.

Do all of these sound reasonably normal for an engine this age? Do any of them sound like the engine is likely to spit a rod and become totally useless or something of this extreme? Do any of them sound like I could do some quick fixes to fix the problems? Thanks.

[Cakky]

its hard to say really lol, its a 4AGE!!, it could keep going for ever, or it could blow up on you when you drive it to work tomorrow!!

best bet is to keep driving it, maintain it regularly and if you really want it to last don't thrash the balls of it, regular maintenance is key really...

[rollaholic]

4A's are so cheap i say ring its balls off till it dies (this will take alot longer than you might think) then replace it with something better

[d1 mule]

4A's are so cheap i say ring its balls off till it dies (this will take alot longer than you might think) then replace it with something better

i agree, and any 4age is better than a red top big port. just get a lowish kms small port the difference will be massive

[sergei]

BTW life expectancy on those is about 400-500kms, they usually die because owners stops feeding it with oil and water (at that stage they consume it almost as much as gas).

[mr30%jr]

got a aw11 with 245ks on the clock only just run the waterpump shaft seal doesnt smoke or anything thats not even the motor thats just general motor thats incredible if you ask me

[varix]

Okay sweet, these are things I like to hear. If the car dies its not going to be worth my time or money putting a new motor in it. So fingers crossed it just keeps on going. Has done so far! Will just have to make sure I have a few containers of oil in the garage as time goes on

[pc]

All the oil seals get old and leak and your stem seals will be the same. The hard vaccuum line on the inlet manifold is probably cracked causing the vaccum/map sensor to read incorrectly, probably causing the popping sound.

*Edit* rubbish that didn't make sense removed

[solitaire]

Had the smallport in my levin since when i bought it at 80,000k's

Abused the crap out of it and didnt keep enough oil in it when i first got it... now at 205,000 it gets a little grumpy at times and you can occasionally hear a bit of clicking... but shes still got plenty of life left in her...

Only problem i have is my dead clutch - which at 125,000k's (assuming it was replaced just before i bought it) is damn fine in my book.

[Punter]

The noises you're describing don't sound like anything major, but in the interest of fuel economy I would track down the missing sensors.

My silvertop's had rattling bearings (for a few secs on startup, till the oil light turns out) for about 10,000km and even with daily thrashings it's still going strong. So you've got nothing to worry about.

[varix]

The airbox was removed before I purchased the car, around 2 years ago. So I am unsure on the MAP sensor, I never realised they were on the airbox? I thought that was only an AFM.

I have the airbox still so perhaps I should put that back in?

What vac line is the hard vac line? What is the easiest way to tell if its shagged or not? Spray some gas around the lines and watch for rev changes?

It would be great to get extra fuel economy as the car is already pretty good, so I would love to get these sensors sorted.

[pc]

The airbox was removed before I purchased the car, around 2 years ago. So I am unsure on the MAP sensor, I never realised they were on the airbox? I thought that was only an AFM.

I have the airbox still so perhaps I should put that back in?

What vac line is the hard vac line? What is the easiest way to tell if its shagged or not? Spray some gas around the lines and watch for rev changes?

It would be great to get extra fuel economy as the car is already pretty good, so I would love to get these sensors sorted.

Opps muddling my words up, but anyway here is a picture of where the pipe breaks
The piccie isn't very good (I found it on the interweb) but the pipe seems to crack under the metal strap that bolts it to the intake plenum. I have 4 of these and they were all cracked, and have had a look at a mates car and his was also cracked. The MAP sensor connects to this pipe, so a leak here will affect the running.

[varix]

Okay sweet, will check that out, if its cracked, should i just chop the pipe back and extend the rubber hose?

I have put the standard airbox back in and plugged in the air temp sensor but the ECU is still spitting code 8 (no/or buggered air temp sensor). Does anyone know where I can purchase a new/second hand sensor?

Also the rubber flexi pipe that runs from the airbox/pod filter to the intake has a crack in it, so unfiltered/measured/sensored air is getting sucked in between the filter and intake, does anyone know where I can purchase another one of these? Id like to get a factory one as it fits perfectly and has the correct holes etc. Obviously.

Thanks for everyones help BTW

[solitaire]

nice tip pc... ill keep that at the back of my mind

[pc]

Oh and to keep on topic, I ran my old bluetop on a dyno down here a few weeks ago (Speedtech). and with the only things changed being Magnatec oil, all the oil seals that can be replaced externally, I/H/E, the 260,000km engine got 81KW at the front wheels.
So these old engines go fine if kept well.