So I have a 1995 camaro Z28 automatic that i just bought for cheap from a older neighbor that was moving away. i pushed it over to my house and began tearing into it, the motor wouldnt turn over by hand so i pulled it and saw there was a hole in one of the heads, lucky for me I had a spare '95 LT1 from a previous camaro i had, the engine only has 67,000 miles on it so i threw it in and it started right up. The problem its having now is when idling it is fine, sounds good but if you accelerate rapidly and just punch the pedal down it turns off and sounds like its running out of gas just sputters and turns off. If you try to turn it back on right after it dies it wont itll just crank but if you wait 5 minutes then give it a try it turns right back on like normal. If you rev it slightly and ease into it, theres no problem it revs right up and sounds great. So today we were trying to figure out if we're losing fuel pressure so we decided to take a spin around the block for the very first time and we found out that the transmission might be bad. It wont shift out of first at all. i was told by a friend that stopped by that there's a hose that connects to the trans that might be disconnected and be the cause of the trans problem since the previous owner mentioned to us that the engine was bad but the trans was still in great shape. The transmission has 115k miles on it. What could be the source of each problem? Am i going to need a new fuel pump and trans? hope not.

 

Did you actually measure the fuel pressure - 1) at idle with the vacuum compensationl line disconnected, 2) at idle with the vacuum compensation line connected, 3) at WOT/max rpm on the road?

Have you scanned it for codes?

Have you checked the rubber inlet elbow to make sure its not torn, or not correctly attached to the throttle body?

Have you checked the TPS voltage?

Have you checked the MAP sensor?

As far as the transmission problem, that should be posted on the "Drivetrain" forum.

 

havent really heard back from anybody on here for a little while but i just really need some help on this. So a local mechanic come over and took a look at the car. I have replaced the fuel pump (using the trap door method, so easy this got the job done under under 30 mins), i put a new fuel filter on it, i changed the spark plugs and wires, replaced the tps with a new unit, checked fuel pressure at the lines again and everything was good with the pressure, new intake elbow because the original one was ripped, and a new AIC sensor as well. Now that i have put a few hundred dollars into it and still havent been able to resolve the problem i really need some help. The mechanic said the engine might be dying out like that because of the dirty MAF sensor i took a look at it today and the previous owner had it descreened and it does look dirty so i cleaned it up a bit but no help. I looked around under the car and i saw that there was a couple wires that looked ripped near the transmission. They went connected to the VSS so i thought that might be why my speedo doesnt work and why my trans doesnt shift out of first. I reconnected them to the original wires and went to turn on the car but now the car wont turn on at all. I went back under and disconnected them thinking i had crossed them or they werent suppose to be connected but still the car wont turn on. Oh i also cleaned the throttle body extensively there was a large black build up in there so i cleaned all of it out. Anybody experience this before or know what may be going on here?

 

You actually did hear back from someone on here, but you appear to have ignored my questions.

What were the exact fuel pressure readings you got with and without the vacuum line on the FPR? Have you checked the fuel pressure regulator for fuel in the vacuum compensation line? Appears you did have a torn intake elbow.

Have you scanned it for codes?

Did you check the TPS sensor voltage, or did you just replace it for the hell of it?

What EXACTLY happens when you turn the key to "start"? Does the starter crank the engine? Does the engine attempt to start? Will it start with a shot of starting fluid?

 

Have you considered your opti..????

 

sorry about that i replied to your posting on my phone but it didnt post my reply. As soon as i turn the key to on the fuel pressure at the lines reads 40 psiwith the vacuum line disconnected it goes to around 46 psi. I checked the vacuum line and it doesnt smell like fuel and there isnt any coming out from it, yea i did have a torn intake elbow. it was torn on the bottom slightly but i replaced it with a good one, i got it scanned today with a tech II by a friend and it threw a code about a bad MAP sensor we actually got it running today the car will turn on and stay on but if you floor it, the engine will just die out and turn off. The friend that scanned it is a mechanic and he said it might be a bad opti, he said the wires might coming off the opti and into a wrong plug and causing it to misfire or the timing might be off and that either of those problems would cause the computer to throw a bad MAP sensor code. Do you guys think what he told me sounds correct? I just dont want to have throw more money into it. im still looking into the VSS problem though. Thank you for the replies though sorry about not replying back early to.

 

There are two MAP sensor codes:

DTC 33 = Manifold Absolute Pressure (MAP) sensor circuit (signal voltage high, low vacuum)

Sets when MAP reads less than 0.24V (corresponds to less than 10kPa, or about a 27"Hg vacuum)

34 Manifold Absolute Pressure (MAP) sensor circuit (signal voltage low, high vacuum)

Sets when MAP reads more than 4.24V at low throttle position (corresponds to about 85kPa, or about 6"Hg vacuum).

Which one did you get? There is no way a crossed plug wire or a faulty Opti would cause DTC 33. The misfires would have to be huge to cause DTC 34. You need to check the wiring, the harness connector and the sensor voltage. The harness connectors are a common problem. They dry out and crumble with age, leaving the contacts loose and causing erratic voltage readings.

MAP is a critical input, because the ignition timing depends heavily on knowing the engine load, as indicated by MAP.

 

It can easily throw a 33 if the engine dies unexpectedly and the PCM thinks it should have stayed running. In that case, it is not a cause, but a symptom or result of something else.

 

Im not sure on what code it was im going to double the tech II tomorrow but i just got the wire diagram right now so thats the first thing ill be checking out ill be sue to post up the results thanks for the replies though. As far as the VSS goes on the connector side i saw today that theres 3 wires that look to have been ripped or cut, but i can only find two wires going towards there that i can reconnect. I cant seem to find the third one. is there a diagram for the VSS wiring i could take a look at or some helpful info on it?

 

The fuel pressure regulator might be dumping too much fuel,causing it to stall.The torque converter lock up switch could be toast.(kinda like when you are coming to a stop in standard trans car, and forget to put the clutch in,and it starts jerkin ect.) I personally before I would start throwing any more money in this car,take it to a good mechanic,throw the towel in,and get it fixed right.Sometimes a bad injector,will mess up your computer to.We are all guessing here.Hope this helps.How many people on this board have replaced the trans,only to find out it was only the cable leading to the trans(electric),was the problem.?Whew.vent.Sorry.Just trying to save you money and agivation.spell check.

 

Shoebox has all the wiring diagrams for a 95, including the PCM/4L60E interfaces. Your 94 will be similar except the torque converter is switched, rather than pulse width modulated like the 95 and newer cars.

http://shbox.com/1/4th_gen_tech2.html#1995_pcm_wiring

Scroll down to sheet 7 of 7.

 

thanks for the ideas and replies guys. I got home today and checked the diagram for the opti that shoe box has and I compared that to the wiring in the car. All the wires actually look to be in the right position. The good news is we reconnected some loose wires that were going into the VSS and we finally got the transmission to shift today. Took if for a little test drive and shifts nice and smooth. Pheeew!! thats one less thing i have to worry about. Im getting close to the point of having the car taken to a shop and have everything looked at the thing is I'm just one of those diy guys I'd rather know whats going into the car and if theres anything wrong with it theres nobody else to blame but myself. Getting close though the issue has me stumped.

 

the VSS is critical to have connected because the pcm will stay in the idle cells causing it to run poorly, as well as mess up the iac follower counts making the rpm's drop between shifts to possibly the point of stalling. Been there