Z28ach

Thanks for your time, i need help asap. I have my 95 z28 with the 350 and have had for a while, all of a sudden last week i was driving and when i accelerate the car, pedal more than halfway, it felt like it was losing power, and all of a sudden the car engine just stopped running and had to roll into a neighborhood. got picked up and went back a few hours and the car cranked for a solid 5 second and started up fine. What could the problem be? Ive had people tell me its my fuel pump, fuel filter all the way to my spark plugs. When i start the car it idles at 1 rpm, that itself isnt normal, and also if i let the car sit while running it'll eventually shake itself to failure, the car itself wobbles and the engine cutouts till it dies. I need help on figuring out whats wrong, please anyone thanks alot!

dmaderaitt

It can be a number of things, I would start at getting a fuel pressure reading, check your injectors and fuel pressure regulator, also make sure they are pulsing correctly at the connectors, then go to the distributor, coil and igintion control module as well as plugs and wires, check you CAT if you got one, then sensors, oxygen sensors, mass air flow, idle air control, throttle position, intake air charge/temp sensor, coolant temp sensor (the one in the water pump), also check the connectors and make sure your getting correct volts and ohms readings from the both the sensors and connectors, hope this helps, got mine in Feburary and replaced all I mentioned above short of the fuel system and opti-spark unit, all my sensors were factory originals with 172,000 miles, I also disconnected the PCM for 30mins while replacing all these parts, may also be the fuel filter clogging up and you dont want that cause it could damage the pump and effect your injectors if trash passes through.

dmaderaitt

Start it and disconnect the MAF, see if it stays running and starts running good again, your light will come on but if it is already on see if you can get it tested to see if anything pops up, mine would idle high than come back down, start running rough and dumping insane amounts of gas, then when it would reach normal idle temps it you cut off and wouldn't let me give it gas, disconnected it and ran fine, connected it and then died out, so I replaced it, then changed my o2s out for new ones

Z28ach

That's the thing im not very car inclined like you are.. Haha im lost... Where is the "MAF" located? And how much did it cost you to replace all that on your maro?

Injuneer

Start with the basics - check the fuel pressure, scan it for codes.

Scanning a 1995 for codes is a problem, because it's got an OBD-I PCM (computer) and an OBD-II style 16-pin ALDL (diagnostic connector under dash) connector. You have to find a shop with an OBD-I scanner, and either a 12-pin to 16-pin adapter plug, or use jumper wires as shown in Shoebox's photo:

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

The tach is calibrated in "RPM X 1,000". When the needle points to "1", it means 1,000 RPM. Is that what you are seeing?

dmaderaitt

If you know anyone that can help you that's somewhat mechanically inclined you can go to shbox.com to get any info needed for these cars, injuneer, frankcpt, and shbox have all helped me getting mine running right, if you lived near me I'd charge you a twelve back just to help you, you can also watch videos on how to check all these items and read on shbox.com with photos, if you can get a Haynes or chiltons manual to have by you when you are doing your checks they are useful for tips.

Now the MAF/mass air flow sensor is on the intake pipe running from your air filter to the intake, the sensor is in between two gray/silver plates wich is the housing.

I would still check your fuel pressure, it should be at 43psi and shouldn't bleed down and hold steady, not sure on the exact numbers but, there are plenty of threads on this, just search or google it.

dmaderaitt

Check your ignition, bad coil or ignition control module may be starting to go, the most likely one of the two would be the control module.

I didn't need to change all of those parts out but, all were original and most were reading a bit off on volts/ohms, the MAF, coolant temp sensor(in the water pump) & the connector, and oxygen sensors were bad on mine, I did all the work my self and saved a ton of money on labor from a shop, I went to auto stores for tool rentals for checking most of these items at home and for some at the store on testing machines they have, a volt meter is always a good thing to have around the house just like a dremel, as for prices I don't remember but, depending on what's wrong with yours it might be a $20 part or $100 part, the main thing is if you want to save money do most of the diagnostics yourself as long as its not internally on the engine you should be fine.

Z28ach

Alright so here's the dealio.. Took the maro to the shop and it wouldn't even run on a diagnostic so the mechanic said I need a new emc, which is going to cost me around 300... :,( Hopefully with this will solve all y problems, or just get me stuck in money pit for this car. Sry it took so long to reply I went outta town but thanks for everything! If this doesn't help then maybe ill have to try what you insisted. Much appreciated.

shoebox

Don't get a new computer. I almost guarantee you will be wasting your money and it will fix nothing. The shop probably does not know your car is OBD-I and tried to use an OBD-II scanner (because the DLC is OBD-II shaped). Common mistake by many unknowing shops.

Z28ach

Yeah that's what I thought at first but when I went in there to drop my car off I explained my situation about going to autozone and advanced auto parts and there scanners couldn't read the any codes at all, and he explained the OBD-1/OBD-2 theory on 95 maros. Even the check engine light comes on( only when the fan behind the radiator kicks on) and he tried to read that and same thing, nothing.. So hopefully this new computer fixesy problems or maybe not. Thanks for the input.

Injuneer

You do not need a new computer. Sounds like he was trying to short the ALDL pins to flash the codes on the SES light. That won't work with a 95 either.

Z28ach

Alright well I'm I'm supposed to go in tomorrow morning to get it installed. Should I tell him I don't want it anymore and to ask about the OBD 2 scanner? I don't wanna **** him over but at the same time don't want to waste money I don't have.

shoebox

Autozone and Advanced don't scan OBD-I cars, so they are no help and add to the confusion. Just tell the guy to use an OBD-I scanner with the correct adapter cable. If he does not have it, tell him he has not convinced you there is a trouble with the computer or if he does swap it and it does not fix it, you get your money back. Computers are one of the most reliable things on these cars.

Z28ach

Right, wasted my time with them. And okay sounds like a good idea. And just today on my way home I felt like it was going to die. Started shaking alot and rpming real low. I can drive it just when I step in the gas more than half way the car doesn't get power and I feel like the engine is about to drop out the front so I gotta ease my way up to speed... Not the reason I got this car. Any idea what that could be?