So... We took the Z into the mechanic, who said it had low compression (150 lowest drivers side bank all low, 155 highest I think). The other bank it 200 - 195. The car had non-matching plugs in it that were fouled, and one plug that wasn't even the platinum variety. We established that it had an electrical fault somewhere (somehow the #2 injector was not getting signal to open, or it was getting constant signal, he confused me). We paid him and I was gonnah try and continuity test that side of that circuit to see if it had something to do with the aging wiring. Long story short: I pulled out in front of someone and got some of that good ole Z32 wheel hop action, and all of a sudden it was running right again. WTF? I guess now we know its an electrical issue, and hopefully we will have the time to replace the injector pigtales on the harness. I did get a number, if anyone wants it, for a guy that tests and repairs ECUs (test = free if its not broken, $175 to diagnose and repair). Anyway thanks for spending some time reading this

 

ez.... not neccesarily. my car did this to the it would run liek a champ for weeks months, then fall on its *** again. then weeks good, almost a week bad, then a few days good, tehn bad for a week, then good at seconds it would hit miss hit miss. then just decided to tell me to do my self. it did this over a 6 month period. i was apparently loosing compression and some how between the static and dynamic compression ratios it would get better and worse and just... akward times. just, dont ignore the problem is all. go and solve the problem. and who is this mechanic?

 

I'm willing to bet it's still an injector... that's a pretty common thing for injectors to do. Did you ever test them? (I don't remember, sorry. I'll go look to see if you did once I've posted this.)

What happens often is that they'll get stuck open (this is due to ethanol) and they'll dump too much fuel, which will cause a misfire. [The excessive fuel can wash down the cylinder walls causing low compression too, as it rinses off the oil.] When you punch it, you're causing the duty cycle of the injectors to approach 100%, which is where the injector is currently stuck. Once you push it, it frees up again and starts working fine, but the problem will come back in the future.

So get the proper spark plugs (that could also be a huge contributor - the wrong plugs, and I don't just mean non-platinum, I mean any non-NGK plug), test the injectors, do another compression test now that it's firing on all the cylinders, and come back to us again.

And it's not an ECU problem, so please don't even consider having someone inspect it. I have never heard of a bad ECU causing a problem such as this (unless you did some horrible wiring job and fried it).

 

way to bust my pinata. I am still gonnah find out whats wrong with it, it still seems to be using a bit too much gas. I didn't personally test the injector individually, I was going to ask the mechanic to but he had it all back together. He did show me the injector pulse tho, and number #2 was definitly not geting any, are u guys sure thats not my issue (ie, not a broken/bent wire). Crap this car is gonnah haunt me I just know it

 

when i tested my injector, it was hardly giving a ohm reading, so its my belief that it was stuck open and washed out my cylinder walls and was the leading cause to loosing compression.

 

This is what I suspect - it's pretty common.

And I didn't mean to disappoint you, but it's better than thinking it's fixed and finding out it's not when it starts having problems again.

It could definately be a bad electrical connection somewhere... but it's SO EASY to test the injectors that it only makes sense to do that before testing any wiring.

 

I must be a real ***** then cause getting those tiny little metal clips off of those connections is damn near impossible for me, got any advice? I'm really worried that if I lose one the car won't be drivable till I find another one

 

lost cause, part the car out and sell me the diff cheap .

 

hmm... metal clips, you speak of the metal retaining clips im guessing, i dotn remember them on my 300, oh well, yeah heres a tip get a medium length uber thin screw driver pry one side up and slide it a so it is proped at an angle, pry straight from the top if it doesnt come off pop the other side a little bit as well then should be a straight pull off. are you like, quazi retarded? lol, jk but seriosly, how you gonna let those little retainer clips get the best of you, dont gotta be a NASA scientist to figure them out.

 

I guess I'm just whining cause I'm thinking ahead to more excuses to make. I'll do it. It probably won't happen till spring break

 

well, im on spring break as of right now, soooo, go do it!

 

Go to Sears... they have a Craftsman mechanics accessory kit for about $15 (comes in a clear/black vinyl case) that comes with a mirror, magnet, two screw grabing tools, and what looks like a dentist's hook thing.

Use the dentists hook thing to pop one leg of the retainer out. Once you have one side out, use pliers (or the dentist's tool still) to pry it off completely. Use the magnet to catch the ones you drop (which will likely be all six - those things are a bitch to remove without dropping).

A small flathead can do it, but I find the dentist's tool thing to be MUCH easier.

Funny thing is, when I bought the kit for the magnet and mirror, I said to myself "what the hell am I going to use the dentist's tool for?" Shortly after, it became my best friend and I use it all the time now. And when I'm not working on the car, I clean the back of my teeth with it. =p

 

Your teeth? Niiiice.