Hey I need a little suggestions I have rebuilt the tbi for a 305 pontiac and have a new fuel pump, fuel filter plugs wires and other things but my car will only start if I hold it to the floor and I have to keep my foot on the gas to idle any suggestions on what this may be?

idk if it's the same as a 92 Camaro w/ the TBI 305, but i think the "hold it to the floor" method does something w/ the ECM and entering clear flood mode per my GMSM.

Btw, the GMSM will list troubleshooting for things like Hard Start - Defined as Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies. I can post pics of the troubleshooting diagrams if you need...

Yes it enters clear flood mode, and yes I would really appreciate it if you could send those.

Also I have replaced the IAC and PCV, so I'm confused as to why it won't start and run. And idle

Thanks!

So I disconnected the one sensor on page 2 for the set timing and had a loud pop like a gun shot and then tried starting and no start.

I've never disconnected my Set Timing Connector. "a loud pop like a gun shot" I've never experienced that unplugging anything. Sounds like a short to ground somewhere... but please be mindful, I'm just a novice w/ a service manual.

EDIT: Did you jump directly to Pg 2 under Important?

It's fine I'm not sure why but I will figure out and keep running test until.its figured out

Has you min idle speed screw been tampered with? I see you mentioned replacing the IAC, what about the IAC relearn and TPS adjustment? Just bouncing reasonable ideas off ya my friend...

No um so how would I do that.. lol thanks

https://www.thirdgen.org/forums/tech...w-surging.html

Post 6

Do you have any more pages in the book that talk about this I have looked at all this just wanna know exactly what the book says

The above pics are all the Hard Start troubleshooting / diagnostic info available unless a part or a problematic area has been identified. Now that I think more and more on it the root question here is not actually Hard Start or Idle related... it's why you have to use the "Clear Flood Mode" to start the car. I believe the car is supposed to run like a POS in clear flood mode, from what I understand the ECM disables the injectors so the flood can be cleared... while troubleshooting have you pulled any plugs to check for a truly flooded engine? Might not be an "Idle Issue" at all...

Have you checked to see if the throttle body is leaking out the prime. It sounds like there is fuel being dumped into the engine at prime causing you to shut the injectors off in order for it to fire up.

How about connecting a scan tool and LOOK AT THE DATA STREAM especially during cranking and idle when first started. Second would be to connect a fuel pressure gauge and see what the pressure is when priming/cranking.