I’m going to preface this with the fact that I’m aware all of the repairs needed will be way more than the car is worth. However, right now, repairing is my only option, and I’m going to be making YouTube (and y’all) my best friends while I give it my best effort to become my own mechanic.

Bare with me while we break this down.

First thing- the head gasket. I took it to my mechanic and he saw that I was losing coolant and he noted that the coolant did not smell sweet. When he tested it to check if the issue was head gasket related, the pressure gauge started bubbling and he said that meant the head gasket was blown. Yay! 🥴 My question is, my car hasn’t been overheating at all. Is there a chance it maybe just needs head gasket sealant? Or at the very least, would it help hold me over while I order a new one and then take on the task of trying to change it out myself? (Seems like quite the overkill for a newbie I know, but I really can’t make it any worse at this point and I have no other options , so, now is as a good a time to learn as any I guess).

Next, I’m feeling a grinding under my gas pedal when trying to accelerate, most prevalently felt between 1 and 2 rpm. This is also when it really has a hard time accelerating. And yesterday it randomly had a period where it felt like it was chugging along. Any idea as to what that issue could be?

When idling, the car almost seems like it wants to stall, like the engine sounds like it starts to slow and then picks back up. Not in a loud obnoxious way, but almost a soft consistent pattern, if that makes sense. Possible alternator issues? I do have to try cleaning (or replacing) the MAF sensors as those were throwing a code.

So yeah, a lot going on. Any and all help/suggestions are so greatly appreciated!

 

I wouldn’t recommend adding HG sealant. It will plug leaks but also plug your radiator. If you’re not overheating and not losing too much coolant you will probably get away with driving it until you get your parts, especially if not travelling long distances.

 

1. You can make it worse, and head gasket sealant almost certainly will. Those pour in sealants will stop up any passage that is the formulation target size or smaller. In a normal, new, healthy, in-spec engine, that would in theory be the head gasket leak. Older engines with unknown history may have all kind of build-up and gunk in the block. You won't actually know what all is going to get "sealed" until after you put that stuff in your engine. Thermostats and heater cores are common items. In fact, the instructions say to remove the thermostat while you are putting the "sealer" into the engine. Not sure how you would do that on a stock Discovery.

2+3 I am gonna say are related to coolant leaking into the cylinder and robbing you of power. At the very least the head gasket should be resolved before added troubleshooting cause you can't troubleshoot with a failed head gasket. What do the plugs look like? I am gonna guess a plug or two are going to be very clean - steam cleaned! Could also be MAF sensor, but I would check the plugs first. If any of them don't look right, then probably all your sensors are fine, but are sending unexpected values to the ECU, because there is coolant being combusted.

I hate to be the bearer of bad news, but if your only option right now is repairing, then you need to find some other transportation option until you can replace the head gaskets. Driving your Disco in it's current state is just begging to make the repair far more extensive and expensive. Next up will be a slipped cylinder sleeve or trashed head, or both, and that will make a head gasket look like a bargain.

 

You should first diagnose that it's ONLY a head gasket and not a defect in the block itself.

 

I am confused how did he check for a head gasket issue with a pressure gauge and bubbling ? You check for cooling system leaks by pressurizing the system and seeing if hold pressure. Now if you are seeing bubbles at the head/block interface that is a problem but normally requires a soap mixture.

Next most modern Anti-freeze does not smell "sweet" it smells like anti-freeze but only if it has not been over mixed with water.

A cracked head gasket does not necessarily lead to over heat, but how are you checking factory gauge or some other method. If the factory gauge you functionally know nothing as that thing will not move until you are in the 230ish range which is way too hot.

Next head gaskets on these are more time consuming than hard, but they do require you access to a good set of tools. As someone who has not has not done this before give yourself a week, you want to go slow and double check as you go. Make a bunch of note and checklists before starting.

Coolant has to go somewhere:

It either gets burnt in which case you get white smoke out the tail pipe. The volume depends on the size of the failure.
Your cooling system gets over pressured in which case it dumps from the coolant tank overflow
It can migrate to the oil, but then you get what is referred to as milkshake, you oil will be whitish from the mixture of oil and coolant
Or you have an external leak.

 

If you run the coolant tank cap one full turn loose from full tight it will dramatically reduce the coolant usage. I have a friend who has been driving his truck occasionally for more than a year like that. Not recommended obviously because of the potential for damaging it further.

 

I’m not quite sure. He didn’t really explain it to me. Just put the pressure gauge in the coolant reservoir and started the car, which cause the blue liquid inside to bubble.

I personally didn’t really smell any sweet, but my nose was kind stuffed from allergies 🤷🏼‍♀️🫣

The temperature in the car isn’t moving at all. The engine was seeming to run a bit hot when I stop and open the hood. But this was as the coolant got lower. I just added more so we’ll see if there’s any difference. When I topped off the reservoir, I didn’t see coolant leaking or dripping out anywhere though. I don’t have white smoke or milky oil.

I just refilled the power steering, and cleaned the MAF sensor which definitely seemed to help. But I’m now noticing a quiet whining sound when accelerating. When I open the hood, it sounds like maybe the alternator is starting to go? But maybe it’s some part of the engine, transmission, or the head gasket. I took videos but it’s not letting me upload them.

I filled the coolant yesterday and drove about 30 minutes, and that’s where it dropped to. So obviously there’s a leak SOMEWHERE

 

@Marggo Ok so so he did an exhaust gas test not a pressure test did the liquid turn yellowish ? Also it is possible you are over pressuring from a small head gasket leak or bad cap and losing coolant from the expansion tank overflow. The simplest way to check this is to add some hose and a bottle if there is coolant in the bottle you have a problem.

Below is what I setup when my head gasket failed I have left in place since, as it is an easy check for over pressure.

 

@Richard Gallant okay, yes. After looking that up, he did the gas/exhaust test. It did not turn yellow, but it was bubbling.

I’m just going to mimic what you’ve done in the photo with the added line and bottle and turn on the car and let it run, correct? If there’s coolant then there’s a problem. If that’s the case, is there further testing that can help narrow down what that problem might be with out taking everything apart?

Any idea about the whining and if it could be the alternator or something worse?

 

@Richard Gallant Also, here are those videos of the engine. I don't know if listening to any of the sounds could help determine possible issues.