eds96ragtop

okay where to begin. 96 z28 65,000 miles. ever since I bout the car 1 year ago it has had a slight lifter knock right on startup maybe 35-40 % of the time it would knock for a second or two. Lately is has been knocking for like 2 minutes or more. and 2 different knocks.
usually I run mobil1 oil and a purolator filter but this last time I could not get the pure one so I had to go with fram. I think that their cheap back flow valve is part of my problem.

So tonight i plan to switch to either the delco pf 1218 or the k&n hp3002 and royal purple 5 w 30

what I wanted to know is has anyone experienced this before.

I work for a reman engine co and some of the guys in warranty think this is not reall unusual and that changing the filter and maybe a lighter oil and better filter will solve the problem.

SECOND PROBLEM
in november I chaged the radiator and all the hoses with the goodyear kit and a new radiator from the dealer spark plugs and wires also did the optispark at that time. it weas all fine and dandy for a while like 3 weeks the temps have become much steadier then the old radiator. It has a new 180 degree thermostat it consistently runs hotter then 190 i did the fan switch mod so i can keep it right around 195 but that is the coolest it will get. now over the couse of the last 3 months I have but in the original 1.5 gal of coolant plus 2.5 gal of distilled water. since then I have put in about 4 more gallons of water I keep ending up with a ton of air in the system and I add more water and bleed it per the manual's instruction but it never works right. the other day i fill it get on the freeway and drive 30 mint shut off and then get back on the freeway 30 minutes stop at 7-11 and when I come out the needle is pegged the fans are still not on and it's like 55 degress out during the 1/2 mile drive home its totally pegged I pull over and shut it off and there is water and steam coming out of the over flow like crazy. I think part of it is not having enough coolant to help raise the boiling point. help.

sory for the long post.

eds96ragtop

ttt need opinions

DonHood

Does the fan switch mod keep the fans from coming on automatically?

Also it sounds like you have a lot more water in there than antifreeze, and that could cause a lot of the probs like you said. Go get one of those coolent testers from Advance or Auto Zone, (ones with the tube and floating *****), and check to see what the ratio is now.

I'd try and bleed it again, air bubbles will cause overheating probs sometimes.

eds96ragtop

to the best of my knowledge the fan switch does not keep them from working normally.

LWillmann

On the coolant issues:

You obviously have a leak somewhere, have you tried replacing the radiator cap?

If it's not hitting the ground, and the system is sealed good, then it's just about down to head gasket.

Wild1

Ed, the worst case scenario is that the head gasket is going. The overflow bubbling is a good indication that air is entering the cooling jacket. If air is constantly being introduced, you will get bubbles in the heads which will create 'hot spots'. Those localized areas will have a tendency to warp, distort, or even crack.

First step, pull your plugs. They should all look identical with a light tan maybe a slight powdery black residue... tan is better. If one plug has been 'washed' with coolant, you've got a leak.

Option, with the engine cold, remove the radiator cap. Start the car. As it warms (you can put your hand on the upper radiator hose) the thermostat will open. If you start to see bubbles, it is very likely you have a blown head gasket.

Option, with the spark plugs removed, run a compression test. One cylinder will be down on psi if there is a blown head gasket.

Also, not all blown head gaskets are coolant related. You could very easily have oil seeping into the cylinder which would make the plug glossy black! If oil was seeping into your coolant, you would definately see a 'chocolate milk' residue on the dipstick... which doesn't seem to be the case here.

However, since you are having issues with both oil and coolant, I would be VERY suspicious of the head gasket.

eds96ragtop

I checked the oil and the water last night the best I can tell they are not mixing at all yet.

I am thinking of getting a gauge to do a compression test.

Wild1

Yep, check the plugs too while you are pulling them out for the compression test. Look for any detonation (pieces of porcelin chunked out of the center electrode).

eds96ragtop

ok so I changed the oil and the filter last night. the noise that I am pretty sure was a lifter that seems to have quieted down alot with the new oil and better drain back valve on the new filter. however now I have a knock a different sounding knock and what seems to be a pretty bad miss and the two of them seem to coincide with each other.

so know 2 questions what is cheapest code scanner that will work on obd2 engines and are our v/c gaskets rubber or cork?
ed

Wild1

Valve cover gaskets come both in either rubber or cork. I opted for the rubber gaskets. A little trick I used is to add some permatex to the backside of the gasket and stick it to the inner lip of the valve cover. They are orange and very flexible... I've been re-using them since 1995.

The cheapest OBD-II scanner I've seen is at Harbor Freight for $40. It flashes the number on a little hand held for codes only. It does not permit Current Data viewing.

eds96ragtop

greg I need you to dumb it down for me. If I want to pull the codes that are causing the ses light I can do it with that 40$ one right? For now that is all I want the code info. does the computer throw a code for excessive knock? witch I have.

Ed

Wild1

Yes, the $40 Code device will pull the codes that are setting your SES light. After three flashes it will reset your computer.

I don't think knock signals set a code... but only if there is a total malfuction of the knock sensor. Otherwise it will only pull timing.

Does that help?

eds96ragtop

that did help. I need to go get that. I just want the codes because I would not know what to do with live data if I had it.

you have to hear the new knock that started it's horrible. I feel bad for my baby.

Wild1

After some testing we'll find the problem...