So im in the process of bringing my disco back from the dead, and have quite a few problems. 1996 disco 1 v8 with 120,000 km

So I am having bad misfiring, as well as codes P1313 and P1318, and it seems to be loosing coolant (it also leaks oil, but i get the feeling thats normal for a rover). I have brand new plugs in it, and wires seem to be fine (i visually inspected and sprayed with water, no sparks) brand new battery, alternator is fine, cleaned MAF, IACV, throttle body and seafoamed it, coolant and T stat is new. Basically what I am looking to know is what to check next, I dont want to replace my O2 sensors if they arent actually the problem, and combined with the other symptoms and reading dozens of other threads it sounds like I might have a bad head gasket (even though my oil isnt milky and when I run the truck with the rad cap open I dont see bubbles, however there is lots of pressure when I open the cap on the reservoir after running the engine). Any ideas what to look at next? I dont want to just throw parts at it, so I want to narrow down whether its the coil pack causing the misfires or the O2 sensors, and find out why I am loosing coolant (it is not leaking onto the floor btw). If it helps, I am running regular gas in it and not premium, but I dont think thats the issue. Any ideas?

 

Doesn’t regular gas makes the D1’s run like crap or am I wrong here? Great looking truck.

 

I have only put about 500km on the truck since I made it just road worthy enough to drive, I am tearing it all apart again this winter to fix the rust and some other stuff that needs done. But I want to sort out the engine before I get to all that. From the time I initially got it running (bought it in a non running state) it ran exactly the same with premium vs regular, but it was misfiring and doing the same thing it is now, and idled rough (fixed this issue), so I figured it didnt make a difference, there is also no audible knocking so I dont think its the fuel, and regular gas wouldnt cause the codes I am seeing, at least I dont think.

And thanks! It actually looks a lot better now, shes cleaned up and painted the wheels black and a few other things. She is gonna be repainted green with new badges and a custom front/rear bumper soon.

 

They run fine on regular.

Coil pack is more likely the culprit over o2 sensors. I would be looking at where is the coolant going. As a blown head gasket can cause misfires. Before you say the oil doesn't look like coffee with cream,. I know Rovers never do

 

Thank you! Best way to test coil pack I am assuming is to use a spark plug tester right? (the kind that lights up on firing?) that should let me test both the wires and coil pack to make sure its not ignition. And I cant seem to find where the coolant is going, it isnt leaking on the floor thats for sure, because I park it inside on a perfectly clean floor and only have a little oil drip, no coolant. Is there any land rover specific symptoms of an HG being bad? I can bring it in to get it leakdown tested but if theres something I can look for or do myself that would be best.

 

How quickly are you losing coolant?
Check the coolant connections to the throttle body heater.
Does the exhaust smell sweet (like coolant)?

You could try a block test kit which examines coolant for the presence of exhaust gasses. They are not always 100% accurate, but can be helpful as a first/inexpensive test.

 

I would say that I lost a half litre over the last few months, but ive only driven it 500-1000km. Looking inside the engine bay there isnt anything visually leaking, although I will go check those specific connections. Are you suggesting that if it is leaking from there it might drip onto the engine and burn that way rather than it being combusted in the chamber? Spent a lot of time staring at the stupid thing wondering what I could do lol. And dont really notice a sweet smell from the exhaust, but if this helps I tried to seafoam it the other day and followed the instructions on the can, the smoke didnt come from the exhaust pipe at all... it came from the engine block (not from the manifold, at least it didnt look like it was from the manifold) could it be possible that a blown head gasket would cause the exhaust to leak out the side like that?

Thanks for the help everyone! Really appreciate the people on this forum.