Any auto mechanics on here?

Haha...that's what I thought too. I love my 01 Tahoe z28, but after that generation they may have outsmarted themselves. (Yes.z28.i put 1984 Camaro Z28 emblems on it instead of the z71 emblem. Everyone should do it.)

Does the neck of the gas tank fill up and shut off the pump every ten seconds?

Of course there's permanent codes. Look it up. They stay in the ECU memory until the ECU decides that the issue is fixed. You can't clear a permanent code with a scan tool. If the ECU decides that the issue is fixed it wipes the code.

Last Edited by Swearbox on 04/14/2022 08:25 PM

Not noticed that.

You must not work on hybrids.

Remove the cylinder 4 plug, check for cracks above the nut below the terminal. Could have cracked it during installation, especially if the socket doesnt have a rubber insert. A crack there allows the spark to ground at the nut rather than the gap.

Do you ever smell gas vapours OP?

The car coded before I changed the plugs. When I installed the new ones I used a socket with a rubber insert. Fairly certain i didn't damage the new plug. I just ordered a new set of ingintion leads which should arrive Sunday so we'll see what happens after I install them.

I miss the old days.

Car running bad? A vacuum gauge could tell you all you need to know.

Cool with the wet spot .

Buy a Code Reader,clear the error Codes and sell it to someone.

That is my advice having suffered a torturous few months with a Honda once.

It was like playing that game "Whack a Mole".

Resolve one Code,then another would Pop up.

So on,and so forth.

Last Edited by Dogsbollocks on 04/14/2022 09:29 PM

Not yet...i think I adopted it after alot of things had to be replaced. Right now it's the cabin stuff that's failing. 20 years is a long time.

P0304 is a misfire on cylinder 4...

If it's not the coil, then it could be the fuel injector or the O-rings causing a vacuum leak. Are you getting the signals from the engine computer to turn on the injector. It also could be a Vacuum leak on cylinder 4. Which means the Plenum Gasket (upper intake manifold gasket) could be causing a vacuum leak. If you have a plastic intake manifold, these are notorious to crack and cause vacuum leaks...

A lot of the permanent codes are from the ABS system...

There are a few that are in the OBD2 system, such as the vehicle going into Limp Mode...

Its warning you it is 2 years past 'end-of-life'

I like this answer as it goes way beyond just plugs, plug wires and coil pack...I hope it isn't this but thanks for the comment.

I work for Autozone, in management, with 20 years experience working there...

fix it and sell it hyundais are garbage.

I recommend selling that Hyundai and buying a diesel

Black tape over check engine light?

Bad piston oil ring on #4 cylinder, seen it many times.

Actually hes right.

Some cars have non volatile memory such as Volkswagen disconnectiing the battery will not clear it.


A vehicle has 3 DTC states. Pending, Active, Historic.

Typically on a vehicle (without volatile memory) that has had the battery disconnected they will all clear, if the code immediately comes back at crank up then the code is still active because the fault is still immediately present (a harness unplugged for example) Some faults require extended monitoring to confirm which is why often they wont become active untill after 3 ignition and run cycles. The vehicle has to go into closed loop. Something like exhaust or evap faults are like this because the fault can be subtle and already things like 02 sensors unless its wideband are not all that sensitive.


Pending codes are when the car has reached closed loop and detects a fault that is

I'm not seeing any of the many signs of bad piston rings.

I need assistance for my 98 jeep Cherokee! The damn starter won't turn ONLY when the jeep is outside in the Sun for more than 10 minutes or so. Literally starts just fine with zero issues when it hasn't been sitting out in the sun. What's up with that shit?!

OP, you need to put 4oz marvel mystery oil into the spark plug hole. Also put 4oz mmo per 10gal of gas in tank. Use up to 25% mmo in crankcase oil. Doin this could loosen the oil ring.

Ok, suit yourself, the oil piston ring is different than the 2 piston compression rings

If it still drive...

Drive till the wheels fall off

Not dissing your suggestion, I'd just rather try and rule out the obvious before having to tear an engine down.

That's how its going to be I think.

.