I have a 95 mitsubishi eclipse, the will crank over and realy wants to start but wont... i just got it back from shop and they put a new wireing harness on it and new plugs.. its getting spark, fuel... and when u crank it, it will raely wannna run " its kinda fires up" for a split second"... but it wont accually start and run... it put a new crank sensor in and then it started and idle'd for about 15 sec.. at 1000 rpm's, then it died and wont start again.. but that was before i got a new wireing harness.. The wireing Harness was the one for crank sensor, and 2 other plugs..... its alot of wires.. but before i had wires going everywere, some werent connected and it would crank but not start " other than the time right after i put the new crank sensor in.. So now AFTER I GET THE NEW HARNESS IT COMES REALY CLOSE TO STARTING Like i said....
I was told that WITH KEY on " not cranking but before that" then the fuel line shoudl PRIM THE GAS TO THE FUEL RAIL.. IT DOESNT DO THAT " DOES NOT".. BUT WHEN IT CRANKS IT WILL THROW FUEL IN IT, I can also HEAR THE FUEL PUMP KICK ON WHEN U TURN THE KEY, AND WHEN I HAD THE LOOSE WIRE HARNESS I COULD MOVE SOME WIRES AROUND and hear the FUEL RELAY kick on and off, but now with the GOOD HARNESS on i can hear somthing kick on but i think its in the other relays..... CAN ANYONE HELP PLEASE... THANKS-chris
Chris, try having a friend turn the key without starting the car, while you put your finger on the first relay. The 420a model Eclipse/Talons have a set of relays on the firewall right by the brake resevoir. The first one facing the passenger side is the fuel relay. It is correct that the relay should energize before the key is fully turned to start the car. If it doesn't turn on, you may have a bad connection still. If it does turn on, then let's move to the next thing.
There are two items that control ignition timing in the motor, one is the crank sensor located...on the crank
. The other is the cam sensor and it's located...on the cam
. Both work to give the ECU upper and lower motor timing and if one is not working correctly, you won't get the injectors or spark plugs to sync with the motor timing which will cause what you are having.
Another thing that will cause this is a bad ASD relay, located on the right side of the fuel relay. That is the on/off switch to injectors and plugs.
Finally there's the ECU. There's not much to troubleshooting this because it's very difficult to say if it's bad because of the amount of sensor info that this thing has going into it. Luckily, there's only 5 thing to track down in a no start situation like yours.
So, make sure you have spark and fuel to rule out the two relays on the firewall, coils, and pump. If you don't already have a Haynes/Chiltons manual, make sure to get one. If those are good, check the cam sensor.
This goes without saying that the basics need to be good too. Things like the plugs and wires, fuel filter, injectors, battery, etc.
*make that 6 things to track down. I always forget the starter motor