If the cat was plugged, the car would run really ratty all the time and would hiss really loud when you pushed on the gas. The egr might make it stall, but it wouldnt keep it from running, I dont think. Check your coolant temperature sensor or air intake temperature sensor, and also inspect your grounds. Especially your battery ground. Those can make a car hard to start when its hot. A combination of stalling caused by bad plugs or wires or vacuum leak combined with the temp sensors or bad grounds might do whats happening to your car. Also check your air filter just for ****s and giggles. Its strange though that these problems arent throwing up any codes. Its an enigma for sure.

 

ok here we go..... grounds ok,air filter good. I took the cat loose at flange and let it run for 2-3 minutes and took off. Only made it a mile and she died. Then it wouldnt start,even after I pulled it back home. Usually after 4-5 minutes it starts and runs for a mile or so. A friend of friend of a friend said sounds like map sensor. so I thought I pulled the wire loose and tried starting it and it worked and I got check engine light too. Well heres the skinny went to autozone asked for a 73 dollar map sensor and it was nothing like what I pulled the electric loose from yesterday. He said mapp sensor was on intake near pcv valve. So what the hell did I pull loose on the passenger side fender well 1 1/2 diameter with 2 black 1/4 size hoses (vac I think),and an electricial connection. I cant find anything online to tell me what iI unplugged to make the car start.
The guy told me the mapp sensor would not make check engine light come on and that his reason for the mapp is that its saying to lean out the fuel which would kill my engine and that after it cooled, would let car start and run until it reached a certain temp and began to act funny making it run lean and not send fuel to injectors. Does this make sense to anybody.
So heres the real question, do I install the mapp sensor or do I find out what I pulled loose and change that. Reason being autozone said once I instal mapp I couldnt return. Whats the vertict now fellas. thanks again

 

That black thing on the left of your engine that is on your motor mount is the cannister purge control solenoid. The map sensor is located on the intake manifold, right behind the radiator. If your car is a 95, it will have the map sensor on the left side of the manifold, and an airtemp sensor just tothe right of it. The MAP will be near the top radiator hose. While I dont think that the purge contol solenoid would go bad, the hoses to the charcoal cannister can go bad and that can cause stalling, but the MAP sensor or the air temp sensor are also culprits. The MAP sensor will throw a code. Either a 13 or 14. A code 23 for the air temp sensor. Code 31 for the canister purge solenoid. Do you know how to "talk" to your neons computer without the decoder from Autozone? Turn the key on and off three times quickly leaving it in the on position on the last turn. The check engine light will flash in sequence two digit codes. Each two digit code has a description.

 

It flashed 3-5-5 if that means anything. Bought a mapp sensor and it wasnt the problem either. Something tells me its heat related. When I unhooked the cat. and let it run 2-3 minutes and took off it die in a mile. Could something with the air box do with it? The air box is right above the exhaust manifold. I hooked it back up today and let it run for 12-15 minute then took off with that cannister purge thing unplugged I made it my usual 4-5 mile run and it died. So a played around and hooked the cannister thing back up, nothing. Then I installed the new mapp sensor and there was no change. I took the mapp sensor back off and I am going to return it. Tell me this, would the o2 sensor cause me this grief?? Reason I`m asking is the one sensor is right there on the exhaust manifold. That sucker could of got hotter than usual with the cat off.

 

I dont know about 3. 13 means the MAP sensor vaccum system has a problem. 55 is the end of message code. I dont think that a O2 sensor would cause the car to just die and not start untill it cooled off. It usually just makes a car run richer and get **** gas mileage because the pcm doesnt read the exhaust mixture of air correctly. My car did this exact same stuff and I went through all sorts of sensors to just figure out that it was the computer partially unplugged. When the car got to a certain temp, it would die and not run untill it cooled. What im thinking is, that if the computer in your car is new and the connections are good, and all of the other goodies that would make a car do what its doing are new/replaced, than maybe youve got a loose/broken wire somewhere. When temperature goes up, so does resistance in conductive materials. A frayed/loose wire might just stopsending signal to vital engine components like the coil or ignition system. That is something that could take a while to sniff out. My 96 Neon had a wire do the same thing as well going to the coil pack. The auto techs ended up putting a jumper wire in to fix the problem. Like I said way earlier, maybe the pros should take a whack at it. One of the only other things I can think of are the cam sensor, and the crank sensor. The cam sensor is located on the drivers side of the head right above the coolant temp sensor. And the crank sensor is under the car just above and behind the oil pan, just next to the oil filter. The coolant temp sensor could also play a role. Other than that, get that gallon of gas and a match ready!

 

i did the crank sensor already

 

tommorow I`ll try the code thing again and see where I stand

 

So, cam sensor, coolant temp sensor, air temp sensor, and faulty wire are the only things left, just about. Basically, there arent any more sensors that regulate the engine other than throttle, and vehicle speed sensors. The next thing to do, other than a shop, is to get the multimeter out and start checking the voltage going to your sensors/coil/pcm to make sure that there isnt a bad wire somewhere.

 

OK the code today i did today myself,I`m done with advise from that shade tree mechanic, 1-2-3-1-5-5 and I have the gas but cant find a match lol

 

The 12 is for the battery connection having been disconnected within the last 50 ignition cycles. The 31 is for the canister purge solenoid, and the 55 is the completion of fault codes. You said that you had unhooked the purge solenoid so that is what popped the 31. If you open the fuse box under the hood and pull the fuel pump fuse for about a minute and plug it back in, the old codes should be cleared. Then start your car to see if any more codes pop back up. The fact that the computer isnt really telling you anything leads me to think that there is a bad wire somewhere. Like I said before, time to get out the multimeter and check for voltage problems to components. Either do it yourself, or get a reputable auto tech to do it. The search could be a real pain in the *** and might just have you going to the store to buy some matches.