Jimny 1999, SOHC, G13BB engine. OBDI

Im a newbie , g'day to everybody. i got given a Jimny! i want to reco it and use it on and off road. It may need a new engine but are about to attempt diagnostics.

check engine light ON, came on on the drive home.
4WD light flashes when 4WD engaged. Prob indicates a fault in the engagement somewhere?
A/C not working, no response from switch on dash.
To disengage 4WD back to 2H , I have to reverse the vehicle and then the lever will disengage to move to 2H..

Starts easy and goes. gearbox and drive-train sound quiet. Has a steering wobble at about 70kms p/hr.
has oil leaks , gearbox and transfer are well oily on outside, there are oil leaks. . Some prob came from rocker cover area but im sure thats not the full story on oil leakage.

First question, On startup the engine has a lot white appearance exhaust smoke, looks whiteish to me, smells of oil but not totally sure of smell. I did a chemical radiator test for water leak from head gasket and block and the test result was negative. no blown head gasket.

The smoke is a little intermittent but is in the warm up period prob the open loop time. Once the engine is warmed the smoke emissions are not noticeable. i have hammered the accelerator (on warm engine) and that produced a heavy amount of smoke from exhaust. Strangely it doesnt smoke all the time. I suspect this engine is dusted and /or valve guides are badly worn? uses oil but i dont know how much as ive only had it a few days. Unregistered as well.

What would be the first thing to do in diagnostics? Would a compression test be the first port of call, what is the compression specifications for the G13BB engine? Im in Australia, we didnt have OBDII standards back then , OBDII was standardised 2006 and afterwards. I believe this jimny has an OBDII port with an OBDI engine management platform. CAnt read anything , used a few different OBDII scan tools and no joy.

Anyway smoke is the engine issue, there are a few other niggles. Is there a list of common problems associated with this vintage Jimny?

A jimny welcome from n/wales

Thanks Mate. beautiful Wales. reminds me Ive got to try and reconnect with an old mate who lives somewhere in Wales, we used to swap emails for years but lost contact.

Hi and welcome.

I would ignore the exhaust smoke at the moment as its clean once the engine is upto temp.
During warm up it could be water vapour in the exhaust as it gets upto temperature.

I would start with a basic service, change engine oil and filter, check plugs are ok. Check for any coolant leaks. If you can then take it for a drive thrash to clean it out then reassess the smoke issue.
If I recall if the aircon has low gas pressure it will not kick in, so it may need a regas or at least get a gauge on it to see if it has any pressure.
Not sure on the 4WD engagement / disengagement procedure as mine is a push button model, some magic occurs under the car, no levers to push. The lever system is much loved, so sure someone will be along to offer help.

Mike

Thanks Mike for the ideas.

I would also say welcome to the forum.

You clearly have several problems but, assuming the Jimny was given to you, you have an opportunity to restore a vehicle (within common sense) without as much expense as many spend.

From what you describe, a compression test would be a good place to start. Before we can give much advice, I would first ask what your skills are in basic auto maintenance. Engine expertise (rebuilding, swaps) ? Diagnosing problems?

One good thing about living in Australia, you should be able to find local help also.

Gday zukebob, i found the EGR valve heavily coked up and the exhaust to inlet pipe orifice completely blocked with carbon. That prob be the initial smoking gun on the emission problem. Ill fix that one and see if that curbs the smoking problem.

I'll do the basics first as you say, do a lube job, fix up the vacuum hosing (leaks), found the EGR valve unit and exhaust gases transfer pipe has a carbon blockage , will attend to that, throttle body removed and cleaned , checked TP sensor and air intake sensor seems to spec.

Will go through the 4WD electrics and vacuum setup to check for faults after engine management resolved.