4age Problems

[Jedi]

Hi,
Ive recently bought a Suzuki Sierra (dont laugh) with a 4age engine (rwd 16v tvis 86kw) in it. The car was sitting in this dude's front yard for god knows how long.
Anyway, it initially wouldnt start so after sourcing an ecu (the old one was burnt out) I fired it up and encountered two problems:

Firstly, it cant hold the revs, ie I try to hold it at 2000rpm on the tacho and the needle drops to about 1000rpm then comes back up to 2000rpm then drops again etc. etc. This happens right through the rev range. Ive changed: tps,dissy cap, rotor, leads, injectors, fuel filter, oil & filter. Im also reading 12v at the coil and have a healthy spark from the plugs when checked against the block.

Secondly, it blows alot, and I mean alot of smoke. Its also a bastard to start. First suspect is the head but after a compression test and teekay head check all seems sweet. Second suspect is the rings so I took it to my mechanic and he assures me its not the rings (this has him stumped too). The smoke is white with a slight blue tinge and smells strongly of petrol.

I pulled my plugs out and cleaned/gapped them, after pulling them a second time I noticed they had oil on them. When I got the car I put about 4litres of oil in it (too much?). Ive also tried it with another ecu to make sure it wasnt contributing, but it ran exactly the same.
When the ignition is on (car not started) I can hear a hissing coming from the fuel rail which sounds like an injector is stuck open but as they are new injectors I cant see this being the problem. Fuel pressure regulator maybe?

Basically Im at my wits end and have no f*cking idea what the go is with this engine
Im still holding on to the vain hope that its something small but I have a feeling the engine is due for a tear down.

Any Ideas guys???

[30psi 4agte]

Hmmmmmmmmmm
Hissing near the injectors ... oil on the plugs..... Have you checked the PCV valve on the rocker cover isnt fu**ed ???


EDIT: oops didnt see the car not running bit !

4L too much !!!!!!!!! GEEZ

[Kebin]

Have you checked all the vaccum lines around the throttle body about the idle problem? the idle control maybe playing up

[Jedi]

Vacuum lines were originally round the wrong way on the TB but they are now right way round.

Forgive my ignorance but whats the PCV valve? I havent even looked at it!

I didnt think 4L would be too much but I thought it wouldnt hurt to ask......

[30psi 4agte]

positive crankcase ventilation valve.

it will be on the drivers side rocker cover. It is a one way valve that vents the crank case gasses.
It should be setup so that the engine sucks gasses from the motor/ rocker cover.

Some times they gunk up and get stuck open causing probs

[Jedi]

positive crankcase ventilation valve.

it will be on the drivers side rocker cover. It is a one way valve that vents the crank case gasses.
It should be setup so that the engine sucks gasses from the motor/ rocker cover.

Some times they gunk up and get stuck open causing probs

Another thing to check. Thanks heaps 30psi4agte! I'll let you know how it goes

[BradW]

Have you checked the cold start injector?

[feral4mr2]

4age's dont use a pcv valve.

is the ecu you have the correct one? eg. the same serial number as the original ecu.

[feral4mr2]

I didnt think 4L would be too much but I thought it wouldnt hurt to ask......

umm.... did you check your dipstick when you poured in the oil? thats what it's there for. cant remember exactly but i think they use 3.5 or 3.8 liters of oil. overfilling doesnt really harm them, but has been known to sometimes cause oil seal leakage.

what were the cylinder compressions on it when you did it?

[Jedi]

4age's dont use a pcv valve.

is the ecu you have the correct one? eg. the same serial number as the original ecu.

Yep, definately the same. Triple checked with the previous owner. And yes, I checked the dipstick, thats how I measured how much oil to put in.

Sorry I cant remember what the comp. readings were but I wrote them down and will post them up tomorrow. There was minimal difference between cylinders.

I forgot to write in the original post that there is neither an AFM or MAP sensor on the engine. The previous owner has sworn blind that the engine was previusly running sweet without them (I believe him) but could that be adding to the dramas?

[Jedi]

Have you checked the cold start injector?

Yep, mechanic checked it and was working a-ok.

[feral4mr2]

I forgot to write in the original post that there is neither an AFM or MAP sensor on the engine. The previous owner has sworn blind that the engine was previusly running sweet without them (I believe him) but could that be adding to the dramas?

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

[BradW]

I forgot to write in the original post that there is neither an AFM or MAP sensor on the engine. The previous owner has sworn blind that the engine was previusly running sweet without them (I believe him) but could that be adding to the dramas?

I wouldn't have thought that an engine with a factory ecu would run without an AFM or MAP sensor.

[Vios-GT_07]

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?

[roadsailing]

bigport won't necessarily have an AFM, i have never seen an AFM 4AGE before in person (i think they liked putting them in aw11s though maybeye)

it will run a lot better with a MAP, haven;t seen one run without a map before. without TPS yes, shittily but not without a MAP sensor

also, 4ages just have a screw to adjust idle speed, not idle motor.

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,

and you dont need a coldstart injector for anything but stopping fuel leaking out of the hole in the fuel rail that supplies fuel to the CS injector.