4age Problems

[Ben Wilson]

bigport 4age should have a AFM, i cannot see how it would run without one.

I've got an MAP bigport out of an AE82 Corolla at home..

[feral4mr2]

I've got an MAP bigport out of an AE82 Corolla at home..

ok so i was wrong, my apologies. ive never seen a bigport MAP apart from the ones over here in the UK.

[RO11LR]

maybe fuel pump , might not be supplying a constant fuel pressure ? but that wouldn't explain the smoke

[Jedi]

Sorry guys, disregard what I said about not having a MAP sensor. I wasnt aware that the Vacuum Sensor on the firewall and a MAP sensor were the same thing, forgive my 4age noobity.

The fuel pump has been bench tested and has been given the all clear. I pulled the vacuum line off the Fuel Pressure Reg to see if any fuel came out but it seemed fine so Im assuming the FPR is working.

Next item on the agenda is to drop the fuel out as it has been in there at least since I owned it (and probably a lot longer). Might not fix anything but it cant hurt.

[Jedi]

take a pic.. i bet there is one somewhere..

sierras are good jeeps.. i'm looking for one... the stock motor is good enough for me but with a 4A-GE it must be really good stuff wish i could find one in good condition and not over-priced... (how much did you pay for it?) good luck fixing it up mate..

with your smoking problem, can it be valve stem seals?

i have a feeling this doesn't have an idle control motor, more like an idle screw of some sort that manipulates the revs.. (read about this on a previous thread but can't remember where).. so your idle problem is most likely vacuum related.. or electronic?

The problem isnt specifically an idle problem as it happens right through the rev range but it definately be vacuum related.

As for valve stem seals; definite possibility. Is there a way to check?

Yeah, Sierra's are tops off-road which is where I do most of my playing. If you end up getting one I give you about two weeks before you retract your statement about the stock motor been good enough
They do unfortunately tend to be overpriced for what they are but if you are patient good ones come along fairly regularly (I was looking for about 3 months).
I paid $1800 for mine which was sprung over, had the (non-working) 4age, 2.5" body lift (which I removed the week I got it) and 31" tyres. If I was going to get a stocker I would look to pay about $1500 and fix it up myself as it is generally cheap and (usually) easy to do so. Check out www.outerlimits4x4.com for more info.

[Vios-GT_07]

thanks for the info mate.. + rep to start you off

erm.. valve stem seals.. if it smokes and the rings are fine it's good to narrow it down so i suggest just get it done.. it's not very expensive iif i remember corectly though i can't say i've ever done a 4A-GE one b4..

so it's spluttering through out the rev range eh? well vacuum is one thing to check for, go over it again just one line that's in the wrong place can have very adverse effects....

i'm going to go with your motor having several problems all at once so i suggest you eliminate it one by one... apart from valve stem seals, you could try a shit load of carbie cleaner to clean out the muck in your ports and go from there?

[Kebin]

to fix the idle, you should probalby plate off the "cold running" bypass, this is the bit under the TB with coolant lines goign to it, you dont need it, but without it you will get a low idle when the car is cold.

check for vacuum leaks,.

check for leaks around the tvis setup too also check gasket seals around TB area make sure everything is tight.
remove the crankcase ventalation hose off ya rockers to see if that does anything about the smoke. see if oil starts spitting out of the rockers

[kingmick]

Sorry guys, disregard what I said about not having a MAP sensor. I wasnt aware that the Vacuum Sensor on the firewall and a MAP sensor were the same thing, forgive my 4age noobity.

The fuel pump has been bench tested and has been given the all clear. I pulled the vacuum line off the Fuel Pressure Reg to see if any fuel came out but it seemed fine so Im assuming the FPR is working.

Next item on the agenda is to drop the fuel out as it has been in there at least since I owned it (and probably a lot longer). Might not fix anything but it cant hurt.

It can be a few things, An injector stuck open or not closing properly if it has a bit of rust, from sitting around awhile, a stuffed oxy sensor so it runs WOT mode. its fuel smoke not oil smoke by the sound of it.

[Jedi]

The injectors are new so Im guessing its not them. Will check the oxy sensor and give the crankcase vent hose thing a go too.

[TooF]

are the injectors clikcing (each of them) put a long screw driver on them and put the handle to your ear, you'll be able to hear each one clicking on and off.. this will give you a good indication if one is stuck open.

[Jedi]

Slight dig.
Pulled the air filter off the front of the throttle body and it was full of an oil/fuel mixture!

Cleaned the TB out and started her up and she ran better (no smoke) but as soon as I opened the throttle (with no air filter on) heaps of Oil/fuel started pissing out of the TB and she started smoking like a mofo again.
Any ideas guys? Im thinking rings again or at least valve stem seals but if there's anything else I should be checking it would be good to know.

If this car was insured it would have had a match in the petrol tank by now.

[30psi 4agte]

Do you have the compression specs yet ?

[TooF]

from the sound of that you are getting buckets of blow by which is spitting the oil back to the throttle..

compression check (wet and dry) then depending on the numbers top end rebuild, bottom end rebuild or both.

[Jedi]

Compression test results (dry) as follows:
Cyl 1: 180
Cyl 2: 180
Cyl 3: 165
Cyl 4: 165

Done using a screw in type tester. I didnt do the test myself but thats what I was told it was.
I thinking something pretty major is going to have to be done, but thats cars hey.

[Gavatron]

You bought this from ebay didn't you. I saw it one there a while ago.