84 duke automatic. Just started driving down the road, got 1.5 miles down the road and the car suddenly felt like it had 10HP, check engine light turned on, and oil pressure went to nothing. Shifted the car to neutral, turned it off, and pushed it into a parking lot. Cranks all I want, but will not start. Checked check engine light, no codes stored. Took off the air cleaner cover, cranked it over some more, and TBI is still dry. Tried switching the AC and fuel pump relays, no effect.

Just walked back 1.5 miles in 80 degree weather with bright sunlight, so haven't tried anything else yet. Fuel pump has never been replaced to my knowledge, bought the car with 147,000 miles, has 180,000 now.

I'm thinking next steps are check fuel pump fuse (thought of that halfway back), check for spark with a spark tester, and try some starting fluid. Is there an easy way to rule out the fuel pump?

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1984 Fiero SE

The only way to eliminate the fuel system (fuel pump) as a problem is to read the fuel pressure during cranking.

HOWEVER

If the fuel pump is not running at all, then you do know there IS a problem in the fuel delivery system.

I would have to double check, but I think you apply 12v to the G terminal (not sure on which one exactly) and if you hear the fuel pump, then it is running. Of course, you could still have a problem where the pump can't get fuel to the TBI, you would have to unhook the connection and check for volume of fuel, and pressure (9-11psi or so).

and pour gas down the tbi...as mentioned to see if this is the problem.

[This message has been edited by jaskispyder (edited 04-16-2012).]

Pulled fuel pump fuse, it's good. Turn car to on, hear fuel pump come on, good sign. Test for spark, set tester gap at stock 0.060, nothing. Try 0.045, still nothing. Check primary and secondary coil resistances, slightly high. Replace coil, fires right up!

The MSD 8226 coil I bought back at the end of 2005 died. Bought a new MSD 5526 to replace it with. The 5526 doesn't have the two holes at the top of the coil for mounting, had to use the bottom two. But it works!

Glad you got it running so quick. If nothing else lesson learned that you can’t jump to conclusions. Always do the basics first (it usually saves a lot of time). Keep in mind that in the 80’s (and early 90’) GM car run much better on stock ignition parts. The ECM makes decisions on how much fuel, timing and other stuff like that based off of know values including how fast and hot the spark is. Starting to change stuff like that will change performance usually for the worse.

By the way, you’ll like the performance out of a stock GM coil over the MSD one. Early GM fuel injection systems run better on stock ignition parts (including plugs). You might also want to check to see if the engine blower is working and that the tubes (one going to the coil) are in place. If not the coil will run to hot and fail early.

The MSD coil does actually work better at higher RPM's where the stock coil falls flat. Normally I'd agree about using OEM ignition parts, especially AC Delco ignition control modules and spark plugs, but the original coil design needs help. The 4 cylinder cars don't have the blower and tube cooling system, that was only used on 85-87 V6 Fieros. Coil failures are common on the V6 cars.

quote The ECM makes decisions on how much fuel, timing and other stuff like that based off of know values including how fast and hot the spark is. Starting to change stuff like that will change performance usually for the worse.

The learn function on these old GM computers is actually a lot better than most people realise. It can compensate for what is functionally a better coil at all rpm ranges easily. The adaptability and diagnostic functions are actually quite impressive given the technology available back then. The problem is the sampling rate, or how fast the computer is, compared to newer ones. If anything the MSD coil is performing more the way the ECM programmers had in mind when they laid out those fuel tables since coil spark energy doesn't drop off at higher rpm's under real-world operating conditions.

Thanks for the feedback on the MSD coils. I don’t have a whole lot of experience with aftermarket coils but I specialized in GM onboard computer systems from the mid 80’s through the 90’s and I replaced a lot of aftermarket ignition parts correcting a lot of drivability problems (it wasn’t at a dealer). If the MSD coil is working better at higher RPM’s my guess is that it’s firing at the same temp and duration as the stock coil but does it for a longer RPM range. Again, good to know, thanks.