93 Buick LeSabre cranks but won't start

[trekman]

The symptom: Turn the key the engine cranks but will not run. If you step on the gas pedal and then crack the engine, the engine starts. Remove your foot of the gas pedal and it dies.

My guess: The TPS? It is acting as if the TPS is bad or out of adjustment causing the fuel to be cut off.

Am I close?

[joshey]

any obd II codes, i would start there first

[Flatrater]

Originally Posted by joshey

any obd II codes, i would start there first

JOSHEY a 1993 Lesabre is not OBD II it didn't happen till late 95 and became mandatory Jan 1 1996.

First of all if the car will not idle I would chase the IAC motor which controls the idle. They get dirty and sticky, start with a goo induction service. You can verify the need be looking at the IAC count on a scanner ideal counts are 16 to 26 at idle.

[trekman]

I do not if any codes are present.
The vehicle is in another city right now.
I intend to "get my hands on it" Wednesday next week. I needed an idea on what I need to research to make my diagnostic time shorter.

[joshey]

ha ha ha ha 1991-on le-sabre and park ave are obd2 thats when they also became electric tranny and the early obd2 conector

[Flatrater]

Originally Posted by joshey

ha ha ha ha 1991-on le-sabre and park ave are obd2 thats when they also became electric tranny and the early obd2 conector

HA HA HA HA HA I am a dealer tech who is a master ASE tech to boot I think I know what I am talking about do you?

So what is the difference between OBD 1 and OBD 2?

[edg]

My '91 LeSabre is ODB One. It has a 12 pin ALDL connector and I read the codes on the SES light by shorting pins A & B together with a paper clip.

[joshey]

short answer, yes i was wrong thanks for correcting me it is '94 on my druken mistake(i only have four down now) as for master tech, ha ha ha ha ha. my grandmother could look at a book for a few months and pass thoes tests. you know what my certs. are...inspectors lic. and nothing more, dont need them after all who give a shoot if r-12 has ance threads, the question is do you know the right way to charge the system, or are you connecting the bottle to the high pressure side and blowing your self up(oh yeah i am a/c cert too(this was taken from the test)) like i say its all book knowledge, i been working on cars trucks and bulldozers from 6yo on. OBD 1 is a name given to the first level of needed (clean air act of what ever the hell date it was) self-diagnostics that specifises that things that make emisions exceed the std be reported to driver in the form of a SES light OBD-1 also need to have a trouble code be stored that can be gotten by a service person. The other things required are some simple test features to acknowledge inputs from some of the sensors and an activation test that operates the items that the engine management operates (injectors, idle control valve, egr valve regulator).
(on most pre 94 buicks)

OBD-2 is a more elaborate requirement that requires any emissions critical part or function that the manufacturer can't assure will have ABSOLUTELY NO FAILURES to be tested.
OBD-2 has different levels and not all cars have as extensive an array of features.
ALL OBD-2 have misfire detection, cady converter monitoring, storage of certin sensor values and operating conditions at fault occurrence, and the capability to have the info retrieved by a scanner tool through a common digital language.
Further testing that is phased in and is on 100% as of 98 yr model (it might be 99 in some cases if the manufacturer earned credits that allowed it to delay [planting trees, dragging beached whales back to sea...... just kidding!!]) is the fuel tank vapor leakage test than many out there are very familiar with.

[joshey]

sorry dident mean to rant but i thought that it was a knowledge test, kinda like a insult(not a short answer)

[trekman]

well gee all this ranting and raving really got me no where.

I got a code of 31, which decoded to the PRND switch. I took the vehicle out of park and back into park and the car started without a hitch. Tell me there is something more than that! Am I losing a transmission park switch.

[danthemanluvatan]

I have seen a lot of prndl switches become loose. They mount on the transaxle under the brake master cylinder. Check to see if the two bolts are tight. If they are loose then you will have to adjust the switch prior to tightening the bolts.

[robinjn_99]

Had the same problem on my 92. Thought it was the TPS, but turned out to be the Idle Air Sensor, located right above the TPS. Take it off and push in the metal plunger like thing, should move. Mine moved in and stayed. $65. and I'm on the road again.