i'm going to pull my hair out...

[stockgp]

and use it as kindling to light my car on fire. for the freaking life of me i can not figure out why the sob won't start. it's got spark, it's got 43 psi fuel line pressure with the ignition off.

 

when i crank the motor it sounds like a dry fire. but i can smell the gas if i crank long enough. the absolute last thing i can figure is a vacuum leak.

 

would that be enough to keep the fuel injectors from providing enough fuel to start the motor? when it does start, it runs like BRAND NEW. the problem is getting it to start.

 

for the love of god help me. i'd hate to have to turn this thing into a pile of ashes after all the work i've put into the interior.

 

oh btw, it's a 90 gp with a 93 gp 3.1

[MonteC]

crank sensor?

[stockgp]

i don't know. what would a bad crank sensor entail?

[GP1138]

crank sensor?

 

He most likely would not be getting spark if the crank sensor was bad.

[manitcor]

use a noid light and actually test for the injector pulse on your injectors

 

also test the AC voltage coming from the crank sensor it needs to be within a certain parameter to have the correct timimg (your hayes book should have the number).

 

A vac leak most likley wouldnt keep it from starting it would just make it run like crap and perhaps stall out.

 

Are you throwing any codes?

[stockgp]

map sensor. that's it

[manitcor]

your throwing a code on the map sensor? Im not sure but that might keep it from running.

[stockgp]

yeah, but i shouldn't be. the map sensor has like 500 miles on it

[Turbo231]

That's a tough one...the smell of gas indicates your getting fuel...you've got fuel pressure even while you're cranking...you've thrown an inductive timing light on each wire to make sure you've got spark in the hole?...with juice and fuel there should be no problem at least kicking off a couple times...it may not run. Pull the cable to the ICM (ignition control module) and check to see if everything is OK...it should be as it is allowing spark...hmmmm...I don't know.

[pwmin]

map couldve gone bad already. tell the parts store it took a shit and get another one. if it doesnt fix, figure something else out. its map based, so it could not start because of that.

[stockgp]

but would that cause it to start intermittently? i mentioned in a previous thread that it's only good for one, MAYBE two starts a day.

[gmrulz4u]

Just a reminder, the MAP Sensor is used by the ECM to determine altitude and barometric pressure when the engine is OFF. Therefore if it is defective, it can prevent an engine from starting by not sending a large enough Pulse Width to the Fuel Injectors because it thinks you're at Sea Level when you're really 2000 feet above, for example...

[z284pwr]

It should "still" be able to start with a bad MAP sensor it would just run extremely rich. Have you pull the spark plugs to see if they are soaked? If they are wet, *soaked* they probably aren't firing......

 

have you tried pulling a spark plug out and turning the car over to see if its sparking....yeah bad idea, but simplest way to determine if you have spark, if they are firing, ensure you have fuel, if so, then it should start.....start the basics and work backwards getting more complex....

[stockgp]

they def have spark. like i said before, fuel pressure is 43 psi with the car off.

 

i'm going to replace the fuel press reg, rail and injectors and see if that helps.

[Regal_GS_1989]

I would bet it is the map sensor. I forgot to hook mine up one time and the car started runnig fine, than rich, than it wouldnt start anymore. As soon as i plugged it back in, it fired right up and ran 100%.