HELP! car starts runs dies

[Dave Sigman]

94 shadow mpfi conversion starts up runs for 5-15 seconds shuts right back off. any ideas?

thanks

hmm im not sure the only problem i ever had with running and dieing was my HEP sensor, its the sensor under your dist cap. sends your ignition to your ecm, if it doesnt work right the ecm reads no spark and dies.

[Dave Sigman]

swapped the hep with known good one same problem I checked the coil with an ohm meter and it was a little out of spec the spark is orangish pretty sure it should be blue maybe its too weak to keep the engine running? either way its borderline I'm going to go get a new coil and see what happens. I'll post results.

thanks again for your help

[Dave Sigman]

I'll I have for codes is 12 and 55 the normal ones

[Dave Sigman]

went ahead and replaced the coil didn't change anything. I'm totaly lost now has anyone else converted to mpfi and this same problem or a similar problem with a tbi car. I hate to have to tear it all apart and put it back to tbi when its so close.

[Dave Sigman]

anybody.... I know a bunch of people have done this conversion.

[bmxrider]

blocked fuel line??

[Dave Sigman]

I've got a guage on it almost 60lbs at the rail I pulled a couple of plugs and they looked ok. what does the ASD do? can I bypass it? I think it might be cuasing the problem.

[Blue Iroc R/T]

Does the car have Factory Alarm? If so, Lock & unlock either door with the key, then try to start it.

Ralph

[Dave Sigman]

think I got it narrowed down injectors may be to big going to swap the 27's for 19's and see what happens. I'll post results

thanks

[contraption22]

Did you check your fuel pressure?

[Dave Sigman]

put the 19's in fired right up apperently the 27's are way over kill when they all fire at once like I have it setup. havn't driven the car yet going over everything to check for leaks and gettin air out of the coolant lines seems to work ok now though I'll post again after its been road tested for driveability. tossed a turbo on it for fun too

[mike mckay]

From what I remember of reading before the 19 lb injectors was what was being used so it probably is what you found.

[Dave Sigman]

runs strong with the 19pounders and 3-5 psi it was pretty easy to do to