Engine was running but now it wont

DRIVINGMAN

MEMBER
1986 PONTIAC FIREBIRD
6 CYL
2WD
AUTOMATIC
178,000 MILES

I have a 1986 PONTIAC FIREBIRD that I just bought. 2.8L MPFI. It didnt run when I got it. The fuel tank was dry so I put some in and after it started it would not idle unless the throttle was held partially open. It was backfireing some untill I adjusted the distibuter. All of a sudden it will not even start. I had a troublr code for the mass air flow but the guy I got it from said he got one. I think it came from a wrecker though.

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

https://www.2carpros.com/articles/car-cranks-but-wont-start

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if okay-check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs,coil's resistances,cap and rotor,distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing

If both fuel and spark is present-check the valve and ignition timing, this will lead you to problems
with compression and valves opening and closing at the wrong time/broken or jumped timing
belt/chain.