I’m looking to purchase a 2004 Discovery with 129k miles. Current owner replaced headgaskets last year vehicle ran great afterwards. Currently runs ok with no overheating but engine makes a cha cha cha sound when running and is throwing codes for cylinder 3 and 6 misfires. What can it be?

 

That is the Rovers way of saying "RUN FORREST RUN!"

 

Well, now, it depends on the price and condition. I recently learned that the exhaust gaskets can easily be installed facing the wrong way. I have a rule that any running 4x4 is worth 2k. There could be more than 1 problem, the misfires and chas may be different problems. You are in a good position to bargain, as to pay someone else for that repair could run $500+. Did the owner do the work? If it was in good condition chassis/body/interior, was green with a tan interior, kept stock, I would offer $1200 and go from there. He is probably asking 3k or so. Too bad. Not many people would risk buying a Rover doing the cha cha with the SES light on. I would.

 

I don’t think he did the work....it does look to be in decent shape but we all know these trucks can be nightmares...

 

Nah, just big tinker toys!

 

Not familiar with the cha, cha, cha sound but as Lisa said it could be a bad exhaust gasket or bad exhaust manifold-to-downpipe gasket. I replace that in my truck last year for around $8, I recall.

Misfires are most often caused by spark plugs or ignition wires that need to be replaced, also known in this day and age as a tuneup. Did the owner replace them when the headgaskets were replaced? The fact that the misfires are on 3 and 6 points to plugs and wires. If the misfires were on 3 & 8 or 6 & 7 that would point to the ignition coils since those cylinders are paired. If the misfires were all on one side that could indicate a faulty oxygen sensor even if the typical O2 sensor codes weren't present.

 

You can have a head gasket blown out on a piston causing the CHA CHA CHA, but having it happen on multiple cylinders is kinda rare unless when the HG job was performed they didn't check the block/heads for being 100% flat and even. You'll know if that's the cause as yes you will have instant misfires, but if you were to look under the hood right after a cold start up you should see the exhaust smoke coming from between the block and head.

I bought an 04 D2 like that with a blown out HG on #6 cylinder. I drove it home, stripped off all the off road accessories and quickly turned around and sold it for 650.00. I honestly should have just kept it as the engine was in very good shape besides that, but at the time I didn't need another LR sitting around.

If you take a flashlight and look at the HG on cylinders 3 & 6 between the head and block you should see a piece of the HG missing or carbon deposits from the exhaust escaping. A cylinder compression test is an easy way to verify that. If that all looks good then yes the exhaust manifold gaskets or the lower exhaust gaskets could be leaking, but they normally sound like a ticking sound vs CHA CHA CHA. The 04 I had sounded like a WWII Spitfire upon startup or an old Harley.

If it's just sounding rough from the misfires I'd stop running it to avoid any damage to the cats, replace both coil packs, wires, and while your at it inspect/replace the plugs. I've messed with several D2's lately with misfires on 1 or multi cylinders (on different coil packs) and the coil packs were indeed INOP.