RS-Chevy-SS

--UPDATE-- Okay so I hooked a fuel pressure gauge up to it today...And when you turn the key to run it only primes to 4 then drops to 2. When you try to start it it jumps to 6 then starts and surges...While it surges you can see the gauge slowly creep up to 8 psi and hold(normal is 9-13) then it will stop surging. Also when you give it a little throttle instead of the pressure holding or incresing it just drops to about 5-7. So my mechanic said its not getting enough pressure at all any time...Change the fuel pump..Already pulled the regulator and inspected..Diaphram is good and sping isnt brokenn. Any ideas?

Its an 89 RS 305 TBI L03 Okay heres what it does....after u drive it and it heats to 220 and u park it and let it sit for about 20 mins....When you go to restart it(If it hasnt completely cooled down to cold)..it will start and idle at 1000 then drop to 300 then go back up and drop again(Surge)....but the thing is that it doesnt do that when its cold...any ideas? Below is a changed part list

Parts:
MAT/IAT Sensor
MAP Sensor
IAC Valve
02 Sensor in Exhaust


VIDEOS
Idling:

http://myspacetv.com/index.cfm?fusea...deoid=17208272

RS-Chevy-SS

BUMP!!

RFmaster

Regulator

Dude, do I have to come out to your place and drop that tank for you????? Enough said . 6 PSI that's carburetor fuel pressure!!!. Time to get a bit dirty - first get as much gas out of the tank as possible - empty tank is a lot easier and safer to drop. Get a quality replacement - AC-Delco or Carter fuel pump. Do not get cheap Chinese made knock -off they last about 6 month and go belly up....

//RF

dimented24x7

iTrader: (2)

It doesnt do it when its cold because the commanded AFR is already pig rich. That makes up for the total lack of fuel pressure. New fuel pump time...

RS-Chevy-SS

LOL RF thanks Man its just gonna be a biotch to change it!! Ive already done it 2ce before! I have the autozone fuel pump with a lifetime warranty on it so ill just pick up another pump and throw it in over the weekend....Thanks for all the help RF lol Yeah i didnt think that was enough FP

RFmaster

Hey - no problem, but before you do the drop boogie do a final visual inspection. Check for pinched fuel lines. Just to be sure..

//RF

RS-Chevy-SS

Just finished! The final inspection didnt reveal any pinched lines....Yeah it was the fuel pump because when I would turn the key to run...It would only prime to about 4psi then drop down to 0 in like one sec...this new pump primes to about 12 psi and drops very very slowly like it should! Still gotta see if that fixes the surging idle after a heat soak problem...but upon test driving the hesitation and stuttering it gone!

RS-Chevy-SS

---Update---

Id like to thank all the people that helped me troubleshoot this issue..Mainly RF...the issue was corrected with the new fuel pump. Thanks all! Also I think i might have noticied a slight hesitation last night...But im not sure.....

RFmaster

Regulator
You welcome

You may want to reset your ECM (disconnect negative battery lead for couple of minutes). The hesitation that you are mentioning may be something else, for example leaky old spark plug wires. It is tough to say. By resetting ECM you will force BLM to re-learn fueling now that injectors are delivering proper amount of fuel. Give ECM a chance to re-adjust.

//RF

RS-Chevy-SS

Thanks RF! I was unable to detect a hesitation last night and this morning...So im going to add that to the fixed list...To be on the safe side I will reset the ECM anyway later on today to clear all those damn 44 trouble codes....

RS-Chevy-SS

Thanks once again RF! I think its safe to say the surging is completely gone...Just got done resetting the ECM reprogramming the Viper alarm system and completely reprogramming the sound system...I think its also safe to say the hesitation is gone! Well that closes the chapter on the surging issue! Thanks All! Until the next issue comes up ill be roaming the boards and helping other L03 Owners!