Help needed to save a 91 from the scrapyard please.

Hello to you all I am desperatley in need of some help trying to save a 1991 J reg 2.4i LWB Frontera fro the scrap heap if I can!

We were given it about 4 months ago and it had been sat for about a year but it went through the MOT with no problems suprisingly.

My stepson is a trainee HGV mechanic and he put new pads and shoes on and fixed a hole in the exhaust and for a while she ran ok for our needs.

There was some issues with the fuel pump and the son in law swapped it out with one from another vehicle and all was fine for about 2 months.

We got a new exhaust section from the cat all the way back and all was good but about 2 weeks ago started loosing power and the truck is now pretty much undriveable.

Son in law is now unable to help any more and I am no mechanic but pretty handy with guidance and have acess to tools and a lift ect at the father in laws.

It starts and ticks over fine and no EM light coes on. As soon as you pop it in gear it is really lacking in power and will get up to about 30mph on the flat.

Engine is not getting hotter than expected.

There is oil in the air intake coming from the head breather pipe and it looses a bit of oil but not much always did do. OIl is clean as a whistle.

The exhaust gets very hot and you can hear loud pops and bangs like fuel exploding in the exhaust.

The air filter is clean and newish and the maf is clean and seems to be working as it should.

y son in law thinks the piston rings have gone but there is no issue with coloured fumes.

It seems to get a bit better when warmed up a bit but limping it back home the other day about 5 iles at 30 the exhaust was alost smoking hot.

any help as to diagnosing and fixing the problem would be greatly appriciated as although old and a bit rusty the family has kind of fallen in love with the thing and we would like to keep her on the road.

Start with the simples first. My two pennies worth is
(a) take the plugs out and check the spark end. Black and oily may be your worst fears regarding piston rings. Then it might be not sparking as it should. White means over heating IIRC. Light brown is good.
Another spark plug test is to remove HT/spark lead one at time to see if it's only running on three or less cylinders.
From there a compression test might be an option to indicate burnt out valves or poor cylinder compression.
Not sure if the 2.4 had a breather hose on top of the rocker cover. The 2 litre C20NE did. The idea was the unburnt gases trapped in the rocker cover could escape through a metal gorse filter and get pushed down the hose back into the sump. The gorse used to get blocked up with oily crud with an effect of potentially choking up the engine top end.
Is the fuel being delivered correctly to the injector rail?

Thanks for the quick response Peter!

A few folks have had a quick gander and there is no discolouration of the exhaust emmisions so they tended to be against the idea of worn rings, I will have a look at the plugs tommorow and see what is what as it's nasty outside right now.

the olny pipe on the rocker is going back into the air manifold and that is where the oil is getting into it?

I am stripping a 2.4i at the moment, that ran fine...Engine is sold, but have all the external stuff as engine is going bare...

Could one of the exhaust's have collapsed internally causing a partial blockage?

The other thing to check is the air hose (from air box to inlet manifold) has not got any cracks on ( if you think it does, electrical tape it and see if it changes it)

Found this on my c20 and ran with very little power

Thanks for the suggestions guys.

Air hose looks good but the cat could be blocked and will get it on the ramp when I can drag it over to the inlaws and get it on the ramp.

If the cat is gone I would be happy as will just take it out and pop a straight pipe in it's place.

Think you can get CAT cleaner for not a lot of money. Might be worth giving that a shot.
From my earlier post, if you have got breather pipes might be worth checking to see if any have blockages. Blocked breather pipes will choke the engine.

UPdate: I just tried the paperclip test a few times and got the code 31 and upon checking the info it came up as the rpm sensor so I tried it again and it had no faults lol.

So it looks like a mechanical problem yes?

what should I be looking for as to the Breather pipes? where are they attached to ect as I said I am not a mechanic.

Another thought I had.

I can't drive for medical reasons so it is the other half, I found out a few weeks ago that redex is only 2 quid in tesco and she has been putting a whole bottle in every time she tops up even if the tank is low and its just a tenner.

Could this have done more harl than good? especially if it comes to a dirty or clogged cat as 26 years of build up could have been loosened and shunted out the back?

Could be a crank shaft sensor on the way out...
Mine went due to the insulation breaking down and earthing out...
Was fun trying to find that problem

It wouldn't show up but when it gets bad it will start dieing when put under load, was fun getting the duck back when I couldn't go above 2k rpm or the engine would die

I take it you mean 2.4 not the 2.5....
It should be on the right side (battery side) of then engine, near the bottom , next to the oil pump.