CheshireCat

I need ideas for things to check. Here's the situation... This morning my Z started up just fine and I drove to my gym. Then a couple hours later I went out to drive to work and the car will not start. The motor cranks and cranks, but it won't start. I pulled the key out and tried to start the car again thinking that maybe the fuel pump didn't presurize the system. Same result. I listened carefully and could hear the fuel pump engage when I turn the key to the run position. I don't have a fuel pressure guage, so I couldn't check the pressure at the rail. I checked the fuses including the injector fueses and ignition fuse under the hood. I wasn't able to check for spark because I didn't have anyone else there to crank the car for me while I checked. I did notice that I didn't smell gas no matter how much I cranked the motor. Of course I am in a well ventilated area, so I'm not sure how much I would be able to smell. I changed the fuel filter about 2 months ago for what it's worth... Any ideas what would cause the car to not want to start all of a sudden?

Thanks,
Steve

944v8inDFW

Sounds to me like it may be your VATS system. If you have another key you may try it. Is the security light on or off?

Of if you have a working key you might try a VATS bypass with the correct resistor.
http://shbox.com/1/4th_gen_tech2.html#pass_key

http://shbox.com/1/air_bag_disc_2.jpg

CheshireCat

I did go get my other set of keys thinking it might be the VATS system. The other set of keys produced the same result. Of course, that doesn't prove that it isn't the VATS system. I'll check out that link to Shoebox's site. Thanks for the idea.
Steve

crash4cyl

as weird as it sounds....the opti. Stock ones have an issue of just going, without warning. Are there any codes at all?? Does the car have spark?? Check ar the coil by pulling the wire off the coil and holding it close to the terminal on the coil..careful as it may shock you..If the spark jumps you know it's not the coil or the sensors in the opti. Then do the same on the spark plug if you can pull the #1 wire...harder then it sounds. If you get spark jumping from the wire to the #1 plug then your opti isn't bad. Then you need to look at air if you're getting gas. You could pull the vac. hose off the regulator to see if there's gas in it..then the regulator is bad. If you have gas and spark, hold the throttle open a little and see if it starts. That would indicate an IAC valve. Just a few ideas..but it's harder to diagnois when you're not there...

Chris

CheshireCat

Okay, I got out my multitester and checked the resistance of the "pellet" on each of my ignition keys. One read about 4000 ohms and the other about 4500 ohms. Unfortunately, one reads near the top of one pellet code range and the other near the bottom of the next pellet code range. Both of these keys have been used recently and have worked. I zero'ed out the multimeter to make sure it was accurate at short. Any idea which pellet code I should try to use for the bypass?

Crash, Thanks for the ideas. I'll have to get someone else to help me with checking for spark. I guess it could be the Optispark. I guess that would be better than the fuel pump...

Thanks again,

FryedClutch

im gonna say its not the vats cause when that goes your car wont even crank so i would go with either the opti or fuel but good findin your prob

med_reject

if u have spark, and you have good fuel pressure, then think about the ignition switch.

CheshireCat

Thanks for the ideas. I just took my laptop and cable over to where my car is stuck and checked for codes using freescan. There were no trouble codes reported. I also verified that all of my dash lights were on durring the "bulb check" but the security light went out just like it should. At this point I don't think it's VATS...
For the record, I still haven't been able to check spark or fuel pressure... I'll have to drag a friend over there after work.

Med Reject, You suggested checking the ignition switch. I don't mean to sound ignorant, but doesn't the fact that the engine cranks when I turn the key mean that the ignition switch is working?

Thanks again,
Steve

944v8inDFW

not true the car will crank with VATS problem just wont start.

CheshireCat

If this is a VATS problem, should I be throwing a code? I noticed that code 46 was for the Pass Key II circuit.

I'm not throwing any codes...

Does VATS shut down fuel or spark?

Thanks again,
Steve

crash4cyl

I always thought the engine wouldn't even crank if the vats didn'd work. I may be mistaken but I thought it killed power to the starter...I may have to check my books again but I think it doesn't crank... But get a FP gauge on your way over there and hook that up as well...un modded they see about 45 psi for the first 3 seconds then it bleeds off. If it bleeds off really fast to zero then you probably either have a bad pump or a stuck injector....And they won't run or run really poor with that as it floods the cylinder.

Chris

CheshireCat

Thanks crash4cyl, I'll stop by the parts store to get a fuel pressure guage. Anything special I should look for in the gauge? I guess it just has to hook up to the valve on the back of the fuel rail???
Thanks again,
Steve

crash4cyl

yup that's it....I think they should have them for $20-$50...usually, I can't remember what I paid for mine....but it's the same size valve as a valve stem on your tires...they sell them with different hook ups for different cars...and make sure it reads well over 50 psi. and since the car is nice and cool it should be really easy to work on

Chris

CheshireCat

Thanks, I guess you are right... The bright side is that the motor won't be too hot to work on... Doh!!!

crash4cyl

yeah, at least you can work on your own, it really sucks for those who can't....Glad I'm not one either Good luck hope you get it fixed.

Chris