... The car (my 94 Z28) was running great.

It was about 11:00 in the evening, and I decided to go to a nearby McDonald's (nasty stuff), and get a bite to eat; it was a week end and the chow hall was closed.

As I sat in the drive through, waiting for my turn to pay for my order, the car simply stopped running. No fanfare. It just stopped as if I had turned the ignition off.

I immediately turned the car back on. My very first thought being that I was simply running extremely low on fuel. It started up with no hiccups.

Then it turned off again about five minutes later - and still in the drive through...

It would NOT start again. Turning the key (if I remember correctly) did nothing. It did not crank or make any other noise (which led me to think it might be the starter). After pushing it out of the drive-thru, I waited a few minutes before I tried starting it again (ensuring the "kill switch" was in the on (allowing fuel) position). It cranked and almost caught. I tried again. It cranked. I walked back home.

A few days later I walked back to the car, I was either going to start it or have it towed, and tried to start it. It fired up perfectly, so I drove it home.

The next day I tried to start it and, once again, it just cranked.

I decided in my infinite stupidity that I needed to replace the alternator and so I did. ~$300 dollars later, with a shiny new alternator, it would not start; Just cranked. I was sure at this point that it was not getting fuel (the idea that the OPTI-SPARK I had paid <$500 to replace VERY recently did not occur). So I put a new $250 dollar fuel pump in. It just cranked.

I had an epiphany and decided to check on what you experts had to say.

Apparently the Fuel Pump Relay was something that went bad occasionaly (doesnt everything?). BUT OF COURSE! It was so simple... I Tried turning the key to the ON position while listening for the fuel pump to prime. Nothing. THAT WAS IT!! It had to be, and so simple! So I bought a new Relay. Turned the key to the ON position and heard the fuel pump prime. Tried to start it-

It just cranks.

TL;DR:
Car will not start. Replaced Fuel Pump, Alternator, and Fuel Pump Relay Switch. Car just cranks.

Any and all assistance is greatly appreciated. Thanks for your time.

 

it sounds as though youre throwing parts at it. use a multimeter to see if the battery voltage is acceptable. if thats ok, go rent a fuel pressure gauge, and see if your fuel pump really is working correctly. if thats also ok, its probably your opti

 

Mother of god.... Could it be the Opti... AGAIN?!

 

What brand Opti did you buy? Did you Loc-Tite the rotor screws before you installed it?

Have you scanned it for codes? Have you tested the fuel pressure, as suggested above? Have you checked the short Opti harness on both ends for corrosion or pin damage?

If the PCM can not find the low resolution signal from the optical cam position sensor in the Opti, it shuts down the fuel system, and sets DTC 16. That code does not turn on the SES light. Spray starter fluid in the intake, and see if it starts when you crank it.

If you suspect the fuel relay, you can bypass the PCM interlocks and the fuel pump relay by applying power to the fuel pump prime connector near the Opti.

 

Thank you for the replies.

Please keep it up.

Fred;

Unfortunately for me, I let a mechanic (the horror and now bane of my existence) have his way with the ******* of my wallet... What the hell it was loose anyways (shame on me).

When you say intake, do you mean to remove the air filter and spray it in there? (I am potentially revealing myself as completely ignorant and I apologize in advance for it.)

I will call and confirm what part SPECIFICALLY they installed. I am almost 100% sure it was an AC Delco Opti.

As soon as I get off work I will test the fuel pressure and get a code reader on it (if Autozone has one).

P.S. Fred, you should be paid for your absolute knowledge of F-bodies.

rv93;

I literally threw parts at the car.. This was obviously my first attempt at getting it to start; it cranked.

 

Ok. I Put the Starter fluid in the intake and attempted to turn it over.. It cranked and caught like it was going to run and then died.

Fuel is not getting to the injectors?

 

sounds like your opti might have went.....

try doing the opti test, and if it fails, theres your problem. if not try checking fuses... check them all and replace any old or ones that look dirty on the inside...

 

How do you recommend I test the Opti-****?

 

inline spark tester. should tell you if youre getting a spark to all cylinders

 

Scan if for codes. That will tell you if its a problem with the optical cam position sensor in the Opti. You can also check for a signal on the white wire from the PCM to the ICM. Shoebox has a guide, or check the "sticky" at the top of the LT1 Based Engine Tech forum's topic listing.

If the optical sensor is healthy, and the PCM is sending the ICM the signal that fires the plugs, pull the coil wire off the Opti and hold it near a ground to look for a spark. If you have spark at the coil wire, put it back on and pull a couple plug wires and check for spark at each plug.

At that point, if you prove you have spark, you are probably looking at a fuel problem.

 

Where would you recommend I purchase a code reader from? It's obvious I need to buy one.

My PCM has OBD-I right?

 

The best thing seems to find an older model AutoXray OBD-I scanner. You can find them on ebay often.

Or get free scanning software for your laptop and a cable. You can do a lot more than just scan for codes.:

http://www.ttspowersystems.com/DataMaster.html

http://andywhittaker.com/ECU/FreeSca...0/Default.aspx

http://www.akmcables.com/

 

There are new scan tools available that still do OBDI. The OBDI is packaged together with OBDII in the same tool. Autoxray, Actron, and some others have these. They're a few hundred bucks. Some even come with the proper cable to use on a '95. I'd look on Amazon for scan tools. If you see a model that fills your needs, then I'd do a search on the name and model number. Amazon prices can sometimes be beat.

 

Mopar, I appreciate your perspective. Thanks.

I'm going to go with the laptop idea.

Ill keep you gentlemen updated.

 

I know its an old thread, but did u figure out what the problem wont start?