I replaced the whole primary fuel rail and PD along with 2 primary injectors, the car turned on for 1 second or 2, throws lots of white smoke then dies then it wont start again. I removed the UIM to make sure fuel is getting through and its O.k, injectors have lots of fuel at bottom. Just to make sure I checked for spark, its good.

Is my FC flooded???
Help please

 

I would say vacuum leak.

 

Vacuum leak?
I will double check but what else should I look for

 

Currently having the exact same problem with my 86 GX N/A daily driver.

Car ran fine up until attemp[ting to leave last night. It will start FINE, idle and rev great....but only for 3-5 seconds, then it shuts off.

I have searched numerous related threads to hear a bunch of people crying vaccum leaks, re-stab the CAS, plug in the AFM (durr, really???)....these aren't the problem. I tried.

THe car is currently being towed home right now so I can evaluate it.

The odd thing, I can start it, quickly get moving and get to 2nd gear....BUT....if I try to bump start it with its own motion, it WILL NOT start. It only starts when you crank it. Also, you do not have to turn the key off after it dying to make it start.

I suspect the fuel pump relay/resistor that modifies the voltage for load/cranking. I will check the voltage to the pump as my first test and report back later with my results.

 

I had a similar problem. The car would start, then instantly flood and shut off. Lots of white smoke etc. It was finally traced to a short in the AFM connector. Once fixed I had no problem. That said, I doubt that it's the problem as it seemed to be more of a "freak" occurrence than a repeatable issue.

A thought though: Have you guys checked your grounding? I had a winter car that did exactly this and it was all due to poor grounding. Again, maybe not your issue, but worth a check. Clip a jumper cable to the negative battery terminal, then the other end to the engine and try start it. If it starts and runs with the cable in place, you have a grounding issue.

 

i would start by checking the intake piping off the AFM, the BAC and bypass air solenoid hoses like to come off sometimes or can be bumped off accidentally and not even known.

 

FIRST: Check compression. If you have good compression, then the flooding is not being caused by this, and you can rule out the engine flooding on it's own.


Do what Karack said..and..

If that doesn't fix it..

Exact-o knife open the AFM (if it is indeed plugged in), and make sure all the proper connections inside are linked.

Then..scout for vacuum leaks.

 

mmmmmmk

First off - thanks for the responses!

Flooding? no, just shutting off, starts fine....every time, fires right up and runs like a charm. But only for 3-4 seconds, no more, no less.

Compression isn't an issue - 110 on all faces.

The car arrived a short while ago and I checked the voltage to the fuel pump with a MM:

Key on - 10-11 volts....
Start - 12 volts
2 seconds after start - 8....6....3....(cardies)....0
turn key back on - 10-11

Where is the physical location of the relay or module that moderates the voltage to the pump? I want to try swapping it for another before I hard do a fuel pump re-wire (wiring is stock as of now)

 

.....just read that S4 n/a's didn't have a relay system for stepped voltage to the fuel pump.......going to go ahead and re-wire.

OK - I think they might have one and the info I read was incorrect.

Either way, just tried jumpering the test connector and it runs like a charm

Ill have to try and figure out which relay/resistor is cooked and replace it as I would rather retain the factory saftey measures (like the roll-over shut off) as opposed to a straight re-wire.