Location: North East Ohio
Posts: 123
My VIN: 5780
Location: North East Ohio
Posts: 123
My VIN: 5780
Ok - based off that info and what you've already disclosed. I would guess that the head gasket may be blown and slowly getting worse, as I previously mentioned. But as far as the sound goes, that seems more indicative of an exhaust leak.
Keep an eye on your oil and make sure it looks correct (nothing milky or bubbly). Next time you change the oil, take note to see if there's any water in it. If its been sitting, it will separate and the water will come out first. If there's water in the oil - change the head gasket(s) immediately. Coolant will ruin the bearings.
Once you figure out where your exhaust leak is (assuming that's what the sound is) then you will be able to hear the engine better and check for misfires or other potential problems.
That's the order I would troubleshoot this in if it were me.
Jeff
Location: North East Ohio
Posts: 123
My VIN: 5780
A buddy said pour some Seafoam in your throttle body and watch for smoke coming out of the area that's leaking.
FYI.. I have not tried this yet..
Q: How do you make a small fortune restoring a DeLorean?
A: Start out with a large fortune!
Vin 16245 (83, 5sp Blk) aka Stinky
Most people are able to smell the sweetness of the antifreeze if the "smoke" is a due to a coolant leak...
Just rent/borrow a coolant system pressure tester from AZ and pump it up to the cap pressure. If the pressure falls, look for external leaks. If you don't find any, it's going into the engine via a bad head gasket and/or a cracked head.
Or, attach the tester when it is dead cold (don't pump it up) and see if the pressure starts to rise as soon as you crank start the engine.
I took a video of Red's exhaust leak noise yesterday so I can compare it when I get the new system in. Have a listen.
I was outside and the rear fascia is off but they sound exactly the same to me. I didn't see any smoke when I was recording it but Red doesn't smoke at all so I wasn't expecting any.
Red
VIN 4534
Born - October 1981
Brought back to life - July 2011
Location: Syracuse, NY area
Posts: 1,032
My VIN: 10287
Club(s): (DMA)
I'm not an expert but I feel your noise is almost certainly the exhaust manifold gasket leaking. My car had a bad drivers side gasket and sounded exactly like yours.
As for the smoke it might not be the head gasket. Does your exhaust have a strong oily/fuel scent? Your mixture may be too rich and the smoke is from all of the burn-off. Might be worth having a look at the mixture control unit and all of the fuel injection hardware. Good Luck, you'll get it fixed
Nick A.
1988 BMW 325is
1982 DeLorean DMC-12
1989 Jaguar XJ6