Guest Anonymous Posted August 22, 2002 Share Posted August 22, 2002 I am experiencing serious pinging at even low boost levels. I just installed another motor into my 300z because the other had some serious blow by and it turns out there was a chunk missing out of my #1 cylinder. The previous motor was put together by an 18 year old kid. It leaked oil everywhere and it had no dipstick. Its detonation was minor compared to that of my new motor. Anyways, I am trying to run stock boost here but the motor still pings (7 lbs). Timing is dead on with about 5 degrees of retard. At stock boost i shouldnt hear the slightest ping. Ive had complications in hooking up my air/fuel. Ah well, ive got a set of 85 turbo injectors that i guess i could try and throw in but i would definetly like to be more educated here. Any ideas or help? Thanks Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted August 22, 2002 Share Posted August 22, 2002 that really didnt make anything to clear.......So, what would make my motor ping at such low boost levels? Considering timing is correct....? Now, the factory knock sensor has never been hooked up, from the previous owner to me. Ive been trying to find where in the harness it wires to but have been SOL. thanks Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted August 22, 2002 Share Posted August 22, 2002 what about fuel? what octane? don't use anything under 91... especially in the summer... also.. hows your fuel pressure? if it is low.. you might go lean..hence pinging.. are you sure its pinging?.. check your plugs..are they very clean?.. any damage to them? are they the correct heat range for your 300 ? hmm can't think of anything better to check..my brain is ready for bed i guess.. becareful. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted August 22, 2002 Share Posted August 22, 2002 You should probably make an effort to get the det sensor connected, that would help. You could have gotten a bad tank of gas. Throw a can of octane boost in it and see if it goes away. I believe 300ZXT's used different injectors depending on what year model. You could look into that as well. I have a fried who could run upwards to 10 psi on his stock 300ZXT with no detonation issues. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted August 22, 2002 Share Posted August 22, 2002 Yea, im running around in circles on this one!! I dont have a fuel pressure gauge nor do i use anything under 93. I have a set of injectors that i know for sure are turbo injectors, but i doubt that is the actual problem here. This is really bothering me because i cant drive my car for more than 20 mins! heres the scenario, It will ping on a cold motor at about 8lbs then when the motor heats up it will ping at the first trace of positive pressure! Then eventually my temp guage makes it way over to 270 degrees! The temp guage is accurate considering i was boiling over... On my old Z i ran 12+ lbs with no pinging what so ever. And i know turbo 300's can handle boost rather well. So heres what i am thinking, it might be the fuel pressure regulator, cause when i take of the vac hose connected to it i smell gasoline in the hose. Now the only way to tell for sure i suppose is with a FP guage, but im a broke as a joke college student just trying to get this thing running decent! oh well, ill find a cure one of these days for the 300's ailments. thanks for anyhelp. Quote Link to comment Share on other sites More sharing options...
1FASTKINGCAB Posted August 25, 2002 Share Posted August 25, 2002 You say it ran up to 270° will it get that hot just siting at idle, or only under boost? Maybe is't a cooling problem Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted August 28, 2002 Share Posted August 28, 2002 1fastkingcab, i think you may be right because i just hooked up an autometer a/f gauge and im running real lean. these lean conditions could cause the chambers to heat up, right? But then, what is going to make me run lean? Ack, I ran a compression check for piece of mind, and every cylinder read 180 lbs or above. However, I noticed quite a bit of build up of crap in the water jackets. Nothing caught my eye but some one brought a good point. All this crap might be in my radiator now......? Im not sure, Cylinder head temp? fuel pump? ECU? injectors? Fuel lines? There really shouldnt be a need for adjustment on the AFM consider its a stock motor and no codes come up on the ECU. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted August 28, 2002 Share Posted August 28, 2002 If you are running lean, you need to address that problem before doing anything else. Lean = Blown up motor if you don't fix it. I would start with the basics, and one is a fuel pressure guage to measure your pressure. I would replace the fuel filters, and since I an not sure what the 300 uses (in tank or out) I can't say if it has a filter in the inlet of the pump like a 280ZX does. I would also run a bottle of fuel injector cleaner (stp black bottle) thru it, but remember that any fuel treatment generally decreases octane. So be careful. If your temp gauge is reading right, you also have an issue there that needs to be corrected. You are asking for a blown headgasket or warped head if you continue to drive it with coolant temps that high. Perhaps a radiator flush would help. Also, boosting on a cold engine is a , so you need to wait until it is fully warmed up before putting the hammer down. Hammer down on any cold engine is not a good thing. You could also clean all the connections on the ecu and maf and see if that helps. Good luck. Quote Link to comment Share on other sites More sharing options...
speeder Posted August 28, 2002 Share Posted August 28, 2002 If you smell gas when you pull the vacuum hose to the regulator off the manifold that tells me that the diaphram in the regulator is bad. (gas on the vacuum side of the diaphram). I made a fuel pressure guage once by getting a hardware store 100 psi water pump guage for about $4.00 and with a tee fitting and some 5/16" injection hose,and inserted the guage in the fuel rail's inlet line ( the one from the fuel filter). I always worried about that guage being deteriorated by gasoline and it never gave any problems through several years of use. It would certainly be good for occasional short use and will be accurate enough to find gross fuel pressure problems. Fuel pressore should be 37psi at idle, 43 with the fuel pump running and engine off. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted August 29, 2002 Share Posted August 29, 2002 Thanks lockjaw, but as of right now i rarely drive the thing. Ive only driven it to see how hot it gets. As for laying down the hammer it really doesnt lay anything down considering theres serious hesitation. I really should get a fuel pressure gauge....any recommondations? Also, if compression is supposed to be between 128 - 160 on vg30et motors, what would make my motors compression be 180lbs and over? My motor idles fine and runs overall fairly good. Which makes it tough for me to determine what exactly is going on. Quote Link to comment Share on other sites More sharing options...
1FASTKINGCAB Posted August 31, 2002 Share Posted August 31, 2002 Originally posted by ascilifared:I noticed quite a bit of build up of crap in the water jackets. Nothing caught my eye but some one brought a good point. All this crap might be in my radiator now......? Im not sure, Cylinder head temp? fuel pump? ECU? injectors? Fuel lines? a build up of crap in water jackets can block heat transfer from the block to the water and prevent the cooling system from doing it's job. (not good) I think it's possible for a car that running hot (above 210°) to give you "Lean" reading because any leftove fuel could still be burning in the manifolds & exhaust system. I'd flush the cooling systemreal good and then check out the Air fuel ratio & temp. and don't let her get up to 270° cause your actual cyl head temps will be MUCH higher than that and will contine to rise even after you cut off the car. I also read that the car is rarely driven, There is a nylon "sock" on the bottom of you fuel pump inlet this will get hard brittle and implode the pump will then suck it in. usualy the pump will fail when this happens but I have heard of some Toy's & Nissan's that continue to run, just poorly. another thing that could screw you on a caw that's not run alot is Water in the gas tank or water in the filter most modern fuel filters will stop the flow of fuel if the element gets water in it. If the element gets wet it will swell up and it's pores will close up If only a little water went through the filter olny part will be closed. good luck Quote Link to comment Share on other sites More sharing options...
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