I recently purchased a non-running Formula 350. It was a good deal, the guy I bought it off of thought it was the Fuel Pump, but I can hear it run and I get about 45#+ of pressure. I can't get the car to start so I cant get a really good reading.

When it cranks, sometimes it wants to fire, and I had it running but it was really rough, like there was some sensor waaay out of whack it would not hold idle, I could only get it to run if I kept my foot on the gas. ( NO SES light. )

I can hear the fuel pump run and I can smell fuel coming from the exhaust, so I do not suspect fowled injectors or a FP at this point. I thought Cold start injector at first because he said he had to pump the gas to get it started sometimes. So I used an 89 BIN to eliminate the 9th injector with no improvement.

Fortunately I have a running TPI setup so I thought I would datalog my ALDL from my running car and compare it to the non starting car. My test method:

I used the same basic BIN just so I could compare, one is a 305 and on is a 350 so I knew there would be some differences.

-- On the running car when I crank my MAF Grams drop to about 4 to 5 but on the non running car it also drops, but its not as fast, it falls off much slower.

-- My load varialbe (LV8) will Drop considerably as well on the running car, but on the non running car it is way higher, its almost pegged and then after a few seconds of cranking it will Drop, some when it tries to start.

-The O2 sensor gives me some readings on the running car (even tho its not in Closed loop.) However, on the non starting car it does not seem to budge. A faulty O2 sensor should not keep it from starting however.

-- The most confusing is the Cooling Fan Duity Cucle is at 0% on the running car but at 101.95% on the non-running car. When cranking. I think it also ran when I got the car barely running.

I am starting to suspect the MAF sensor, but that does not explain the Fan or the O2 sensor. I also thought the car would still run without the MAF sensor.

On another note, If I use the original 87 Chip the Batt Volts and Fuel Pump Volts fall to ZERO when I crank the engine.

John

 

Make sure that VATS are disabled o the new car. Are you getting spark or fuel injectors puling while cranking? Is timing waaaaaaaay retarded or advanced? Are the injectors the correct size. Have you ohm tested the injectors?

 

I am going to see if I can check the timing this weekend... Kinda hard by myself and car not running. I have gotten it to run, but it would not hold idle.

Checking the Ohm resistance on the Injectors sounds like a good place to start too I did not think of that.

thanks

 

No VATS on a /87. That came later.

 

My 89 will run without the MAF. Not well, but it'll start and hold a real choppy surging idle with no extra throttle.