Tyler95

Hey guys, I'm new here and I'm pretty new to Camaros, my fiances aunt has a 95', when you try to start it the engine just cranks with no fire, and as it winds down it kindve pudders and shakes, anyone have any ideas? I've seen opispark posted everywhere, but you guys are the experts, so what do you think? If you need anyone info please ask, thanks again.

slick1hunting

With most things its good to scan for codes(95 is obd1 and alot of places have trouble with that). Getting an aldl cable and using a laptop with the software posted in the sticky at top of forum is a great way to go if you want the ability to scan it a look at live data. Checking the fuel pressure is a good idea as well(also while doing that watch for leakdown after prime or shut off as may have leaky injectors or fpr or checkvalve in pump. Does it run ok once started? If you have not found this site yet I would bookmark it as its a very very good resource 4th Gen LT1 F-Body Tech Aids Posted from Camaroz28.com App for Android

Tyler95

The car doesn't fire at all, so there's nowhere I can take it. So is obd1 different than obd2? I was thinking of getting one just to pull the code.

Injuneer

A 95 Z28 has an OBD-1 computer (PCM) and requires a "real" OBD-1 scanner. You cannot scan it with an OBD-2 scanner. You can't short the ALDL pins to flash the codes on the SES light.

It gets complicated, because the ALDL connector that you plug into has a 16-pin OBD-2 style connector. You have to have an OBD-1 scanner with the correct 12-pin to 16-pin adapter plug, or use jumper wires as shown in Shoebox's photo:

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

You can also download free scanning software as mentioned above, but you still need to buy a cable.

Tyler95

Yeah, I understand why it wouldn't work, just not too familiar with Camaros so thanks for the help, I'll get the cable then, seems to be the best option as it's not that much. I'll report back when this is done.

slick1hunting

I made a mistake in my post as I had two thoughts going and obviously couldn't decide which one. I meant alot of places have trouble scanning the 95obd1 for codes(I will edit it above for any other reader who may come across it). Along with scanning for codes I would be checking for spark and fuel. There is a sticky at top of forum on testing the opti. I would also look or consider the icm, coil(look at fuses), and even something in ignition circuit. Make sure you hear the fuel pump run at key on also. I would check its pressure and watch it for leakdown just to eliminate that step since it is very quick and easy to do.


Posted from Camaroz28.com App for Android

Tyler95

Well.. the fuel in there is about 8 years old, there's a filter so I can't syphon the tank, and its overly full.. any ideas how to get it out besides dropping it?

slick1hunting

Whats the filter like? Is it a strainer basket in the filler neck or something?. Tank is not easy to drop and probly worse with alot of fuel in it. One option would be to cut the trap door for replacing fuel pump and syphen there. I am not sure if you could diconnect fuel line and use the fuel pump to pump it out without damage. I cant remember how the return line is if it could be used to siphen.


Posted from Camaroz28.com App for Android

x Wild Bill x

As long as the fuel pump is in working order, you can disconnect the supply line to the fuel rail and put it in a bucket. Then, in the wiring harness near the PCM on the firewall, there will be a little connector that is not plugged into anything. This goes to the fuel pump, if you apply 12V to this plug it will turn on the fuel pump and empty the tank. I've done this before and it works great.

Tyler95

So, how could I apply the battery to the connector? I don't have the car in front of me so I'm not sure, any way to break it down more? Its on the right side of the motor, along the firewal, I know there's like three lines running back to the firewall that are together, I'll have to look for what you're referring to, the fuel pump seems to be in good working order, I can hear it.

x Wild Bill x

I understand it's hard to visualize, but once you are at the car it will be clear. For help, check out Shbox's website. This page: 4th Gen LT1 F-body Tech Articles about 3/4 the way down describes the connector, use your web browser and search for "fuel pump prime". He is a picture of the wire: http://shbox.com/1/fuel_pump_prime.jpg

Just take a small wire from the positive battery terminal, and touch it to that wire and the fuel pump will turn on, pumping the fuel out of the disconnected line, emptying the tank.

Tyler95

Thanks for so much help, you're awesome. I wish I was at the car to work on it. I'll get a cord for the laptop and scan it and report back, after draining the fuel. Do you guys frown upon other cars here? Not hate them but you know.

Tyler95

Alright, I know its a long time coming, but if you guys are still out there to help here what's happening, i be tested to see if there was spark, and there is, now I don't know about the opti being completely healthy, I just think if there was spark it would fire or at least try, and misfire. I've checked all the fuses, ICM, and the ignition coil, all checked out perfect. I still haven't pulled any codes, do you think it would tell me what's wrong, or pile on a bunch of stuff it thinks it it? Any one else have any ideas after those things I've listed?

4th Gen 4 Life

Apparently the car has been parked for 8 years correct? Did she tell you why the car was parked in the first place? Also getting fresh fuel is the first step in fixing. I've seen cars not crank just from buying bad fuel from gas stations. Plus the octane in fuel now days is low so rotten gas would cause the car to not start. Also once you replace the fuel you could prime the old gas out of the fuel lines by the fuel pressure valve. You do this by turning the ignition on then press the fuel pressure valve to bleed the fuel and repeat the same process over until you get fresh fuel to the intake.

94 Z28 LT1 4L60E- Mostly Stock 3" Cat back Blowmasters. Chrome rims +5 HP

Tyler95

She said that when she parked it, they had been driving and she was low on gas, went to get gas, got to her moms house, then when she came back out it started really rough, when she drove back home it was running rough, when she got it there she couldn't get it started back. Before me she's replaced allot of difference things of what people have recommended, I'm not even sure what all was done in whole, she's never replaced the Opti. I know that for sure, but like I said it does have spark, and found think it would at least fire a little. I'm sure I could find a picture somewhere, but do you know where the fuel pressure valve is located? Is other any way I can get it fresh gas without going through the pump? Thanks for the help and your time by the way.