Went

Geeze no, buying parts does not make me feel good. Except those parts be headers, cam and the like. I also like buying a new gun, tools and parts for my bench top CNC machine build and vintage stereo stuff. It's just the O2 sensor now has come up a couple times. They are cheap. I just asked "How would a defective O2 sensor cause the problem I'm seeing?" If I understood what part the O2 sensor played here maybe it would be worth the changing it.

BlowerWorks

Just checked the 1988 - same ! My scanner is not connected to this new PC. I only ask you look - I am not that stupid ! I would be happy to call you and explain to you if you give me your phone number ~!!! My email is: greg@blowerworks.net
I'd love if ARBEE step in here and either help me or condemn me !!!!!!!

PatternDayTrader

He will condemn you.
I will too, if you continue with the idea that the wrong answer, is actually the right answer.

aklim

When you start up the engine it is in open loop. IOW, the ECM doesn't care about your O2 sensor since it isn't going to be working till it gets hot enough anyways. There are certain conditions. Coolant temp and it has to have run for a certain amount of time with no issues that the ECM will go into closed loop and take feedback from the O2 sensor. Outside of that, it doesn't care. It goes off certain tables and assumes everything in the table is right.

BlowerWorks

OMG - I cannot believe you all ! Put your thinking cap on ........ why does the L98 start and then stall if what you say is so ?????? NO - please - I have been looking at the L98 for 30+ years and I PROMISE you what I say is true !!! It's so simple if you look at the FSM. What more can I say ? I asked ARBEE to chime in BECAUSE this is his cause: FALSE INFO !!!

What "you" say about what runs the factory fuel pump is so FALSE - please read the factory manual !!! If you pulled the oil switch connector and your car continued to run - well ??? Bad relay ????
I ask ANY of the hundreds who read these threads to pull their connector to the oil pressure switch and TEST. I bet you car will start and then STALL ! After this I give up on FAKE NEWS ! lol

PatternDayTrader

While it not impossible the o2 is causing you this problem, its pretty unlikely.

So the purpose of the o2 is to measure the oxygen content of the exhaust gas. A high level of oxygen left over from the combustion process, means there is insufficient fuel in the air/fuel mixture. A low level of oxygen means there is an excessive amount of fuel in the air/fuel mixture.

As a side note. This is the concept that causes nitrous oxide + additional fuel to make so much more power. Nitrous oxide breaks down at combustion temps releasing more oxygen than there would otherwise be. The additional oxygen allows more fuel to burn than what otherwise would. Burning more fuel (in the same amount of time) results in more power.

PatternDayTrader

Holy cow pal ... You don't just have egg on your face, you are buried in dogshit.

BlowerWorks

Thank you ! I seriously hope 'someone' will prove me wrong ! Now I know why ARBEE hates me so !!!!!!! LOL

PatternDayTrader

Is there a circuit numbered 458 on your schematic ?

Went

I didn't mean for all this argument to happen. I was mainly just venting. You know, everything seeming to happen all at once? Well hoping too for something quick and simple that would fix it. How often does that happen though? I'll just take my Vette to the shop.

BlowerWorks

It's simple: if engine starts on CRANK and then stalls - replace Engine Oil Sensor and report back !!!!!! OMG I just cannot believe all the "FALSE INFO" here . There must be other mechanics that read this and will confirm what I say ????? Just read tghe "f...cking" FSM !!!!!! greg

PatternDayTrader

​​​​​​​No one ever does. Don't let it bother you. Instead, think of it as debate ....

PatternDayTrader

​​​​​​​No one is going to confirm what you are saying, no matter haw many times you repeat yourself.

Benny42

BlowerWorks

OMG - I repeat "only in crank mode" - yes in parallel but READ - only in crank ! After this I declare all of you who believe "them" IDIOTS ! lol

PatternDayTrader

​​​​​​​We can all read. Now stop punching yourself in the *****.

Benny42

This is what you posted. It is not right. The ECM will run the fuel pump as long as the distributor is turning. Low oil pressure cut-out on TPI cars is a MYTH. Stop perpetuating bad information.

aklim

Before we go there, has anyone ascertained that the wiring is the same in all years of the C4?

PatternDayTrader

We don't need to. We are smarter than that. I know its tempting, but don't start punching yourself in the ***** too ....

BlowerWorks

My Apologies to all - I was WRONG ! Written FSM says relay will remain energized as long as ECM receiving reference pulses ! I am really sorry ! So much for my experience !!! greg